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Guenaga J, Alirezaei M, Feng Y, Alameh MG, Lee WH, Baboo S, Cluff J, Wilson R, Bale S, Ozorowski G, Lin P, Tam Y, Diedrich JK, Yates JR, Paulson JC, Ward AB, Weissman D, Wyatt RT. mRNA lipid nanoparticles expressing cell-surface cleavage independent HIV Env trimers elicit autologous tier-2 neutralizing antibodies. Front Immunol 2024; 15:1426232. [PMID: 39119336 PMCID: PMC11306127 DOI: 10.3389/fimmu.2024.1426232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2024] [Accepted: 06/13/2024] [Indexed: 08/10/2024] Open
Abstract
The HIV-1 envelope glycoprotein (Env) is the sole neutralizing determinant on the surface of the virus. The Env gp120 and gp41 subunits mediate receptor binding and membrane fusion and are generated from the gp160 precursor by cellular furins. This cleavage event is required for viral entry. One approach to generate HIV-1 neutralizing antibodies following immunization is to express membrane-bound Env anchored on the cell-surface by genetic means using the natural HIV gp41 transmembrane (TM) spanning domain. To simplify the process of Env trimer membrane expression we sought to remove the need for Env precursor cleavage while maintaining native-like conformation following genetic expression. To accomplish these objectives, we selected our previously developed 'native flexibly linked' (NFL) stabilized soluble trimers that are both near-native in conformation and cleavage-independent. We genetically fused the NFL construct to the HIV TM domain by using a short linker or by restoring the native membrane external proximal region, absent in soluble trimers, to express the full HIV Env ectodomain on the plasma membrane. Both forms of cell-surface NFL trimers, without and with the MPER, displayed favorable antigenic profiles by flow cytometry when expressed from plasmid DNA or mRNA. These results were consistent with the presence of well-ordered cell surface native-like trimeric Env, a necessary requirement to generate neutralizing antibodies by vaccination. Inoculation of rabbits with mRNA lipid nanoparticles (LNP) expressing membrane-bound stabilized HIV Env NFL trimers generated tier 2 neutralizing antibody serum titers in immunized animals. Multiple inoculations of mRNA LNPs generated similar neutralizing antibody titers compared to immunizations of matched NFL soluble proteins in adjuvant. Given the recent success of mRNA vaccines to prevent severe COVID, these are important developments for genetic expression of native-like HIV Env trimers in animals and potentially in humans.
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Affiliation(s)
- Javier Guenaga
- Wyatt Lab, Department of Immunology and Microbiology, Scripps Research, La Jolla, CA, United States
| | - Mehrdad Alirezaei
- Wyatt Lab, Department of Immunology and Microbiology, Scripps Research, La Jolla, CA, United States
| | - Yu Feng
- Wyatt Lab, Department of Immunology and Microbiology, Scripps Research, La Jolla, CA, United States
| | - Mohamad-Gabriel Alameh
- Weissman Lab, Penn Institute for RNA Innovation, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Weissman Lab, Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Wen-Hsin Lee
- Ward Lab, Department of Integrative Structural and Computational Biology, Scripps Research, La Jolla, CA, United States
| | - Sabyasachi Baboo
- Scripps Consortium for HIV/AIDS Vaccine Development (CHAVD), Scripps Research, La Jolla, CA, United States
| | - Jocelyn Cluff
- Wyatt Lab, Department of Immunology and Microbiology, Scripps Research, La Jolla, CA, United States
| | - Richard Wilson
- Wyatt Lab, Department of Immunology and Microbiology, Scripps Research, La Jolla, CA, United States
| | - Shridhar Bale
- Wyatt Lab, Department of Immunology and Microbiology, Scripps Research, La Jolla, CA, United States
| | - Gabriel Ozorowski
- Ward Lab, Department of Integrative Structural and Computational Biology, Scripps Research, La Jolla, CA, United States
| | - Paulo Lin
- Acuitas Therapeutics, Vancouver, BC, Canada
| | - Ying Tam
- Acuitas Therapeutics, Vancouver, BC, Canada
| | - Jolene K. Diedrich
- Paulson Lab, Department of Molecular Medicine, Scripps Research, La Jolla, CA, United States
| | - John R. Yates
- Paulson Lab, Department of Molecular Medicine, Scripps Research, La Jolla, CA, United States
| | - James C. Paulson
- Wyatt Lab, Department of Immunology and Microbiology, Scripps Research, La Jolla, CA, United States
- Paulson Lab, Department of Molecular Medicine, Scripps Research, La Jolla, CA, United States
| | - Andrew B. Ward
- Ward Lab, Department of Integrative Structural and Computational Biology, Scripps Research, La Jolla, CA, United States
- Scripps Consortium for HIV/AIDS Vaccine Development (CHAVD), Scripps Research, La Jolla, CA, United States
| | - Drew Weissman
- Weissman Lab, Penn Institute for RNA Innovation, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Weissman Lab, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Richard T. Wyatt
- Wyatt Lab, Department of Immunology and Microbiology, Scripps Research, La Jolla, CA, United States
- Scripps Consortium for HIV/AIDS Vaccine Development (CHAVD), Scripps Research, La Jolla, CA, United States
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2
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Del Moral-Sánchez I, Wee EG, Xian Y, Lee WH, Allen JD, Torrents de la Peña A, Fróes Rocha R, Ferguson J, León AN, Koekkoek S, Schermer EE, Burger JA, Kumar S, Zwolsman R, Brinkkemper M, Aartse A, Eggink D, Han J, Yuan M, Crispin M, Ozorowski G, Ward AB, Wilson IA, Hanke T, Sliepen K, Sanders RW. Triple tandem trimer immunogens for HIV-1 and influenza nucleic acid-based vaccines. NPJ Vaccines 2024; 9:74. [PMID: 38582771 PMCID: PMC10998906 DOI: 10.1038/s41541-024-00862-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Accepted: 03/14/2024] [Indexed: 04/08/2024] Open
Abstract
Recombinant native-like HIV-1 envelope glycoprotein (Env) trimers are used in candidate vaccines aimed at inducing broadly neutralizing antibodies. While state-of-the-art SOSIP or single-chain Env designs can be expressed as native-like trimers, undesired monomers, dimers and malformed trimers that elicit non-neutralizing antibodies are also formed, implying that these designs could benefit from further modifications for gene-based vaccination approaches. Here, we describe the triple tandem trimer (TTT) design, in which three Env protomers are genetically linked in a single open reading frame and express as native-like trimers. Viral vectored Env TTT induced similar neutralization titers but with a higher proportion of trimer-specific responses. The TTT design was also applied to generate influenza hemagglutinin (HA) trimers without the need for trimerization domains. Additionally, we used TTT to generate well-folded chimeric Env and HA trimers that harbor protomers from three different strains. In summary, the TTT design is a useful platform for the design of HIV-1 Env and influenza HA immunogens for a multitude of vaccination strategies.
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Affiliation(s)
- Iván Del Moral-Sánchez
- Department of Medical Microbiology and Infection Prevention, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
- Amsterdam Institute for Infection and Immunity, Amsterdam, Netherlands
| | - Edmund G Wee
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Yuejiao Xian
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Wen-Hsin Lee
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Joel D Allen
- School of Biological Sciences, University of Southampton, Southampton, UK
| | - Alba Torrents de la Peña
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Rebeca Fróes Rocha
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - James Ferguson
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - André N León
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Sylvie Koekkoek
- Department of Medical Microbiology and Infection Prevention, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
- Amsterdam Institute for Infection and Immunity, Amsterdam, Netherlands
| | - Edith E Schermer
- Department of Medical Microbiology and Infection Prevention, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
- Amsterdam Institute for Infection and Immunity, Amsterdam, Netherlands
| | - Judith A Burger
- Department of Medical Microbiology and Infection Prevention, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
- Amsterdam Institute for Infection and Immunity, Amsterdam, Netherlands
| | - Sanjeev Kumar
- Department of Medical Microbiology and Infection Prevention, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
- Amsterdam Institute for Infection and Immunity, Amsterdam, Netherlands
- Department of Biochemistry, All India Institute of Medical Sciences, New Delhi, India
| | - Robby Zwolsman
- Department of Medical Microbiology and Infection Prevention, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
- Amsterdam Institute for Infection and Immunity, Amsterdam, Netherlands
| | - Mitch Brinkkemper
- Department of Medical Microbiology and Infection Prevention, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
- Amsterdam Institute for Infection and Immunity, Amsterdam, Netherlands
| | - Aafke Aartse
- Department of Medical Microbiology and Infection Prevention, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
- Department of Virology, Biomedical Primate Research Centre, Rijswijk, Netherlands
| | - Dirk Eggink
- Department of Medical Microbiology and Infection Prevention, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
- Amsterdam Institute for Infection and Immunity, Amsterdam, Netherlands
| | - Julianna Han
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Meng Yuan
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Max Crispin
- School of Biological Sciences, University of Southampton, Southampton, UK
| | - Gabriel Ozorowski
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Andrew B Ward
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Ian A Wilson
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Tomáš Hanke
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Joint Research Center for Human Retrovirus Infection, Kumamoto University, Kumamoto, Japan
| | - Kwinten Sliepen
- Department of Medical Microbiology and Infection Prevention, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
- Amsterdam Institute for Infection and Immunity, Amsterdam, Netherlands
| | - Rogier W Sanders
- Department of Medical Microbiology and Infection Prevention, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands.
- Amsterdam Institute for Infection and Immunity, Amsterdam, Netherlands.
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, NY, USA.
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3
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He W, Ou T, Skamangas N, Bailey CC, Bronkema N, Guo Y, Yin Y, Kobzarenko V, Zhang X, Pan A, Liu X, Xu J, Zhang L, Allwardt AE, Mitra D, Quinlan B, Sanders RW, Choe H, Farzan M. Heavy-chain CDR3-engineered B cells facilitate in vivo evaluation of HIV-1 vaccine candidates. Immunity 2023; 56:2408-2424.e6. [PMID: 37531955 PMCID: PMC11092302 DOI: 10.1016/j.immuni.2023.07.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 05/09/2023] [Accepted: 07/05/2023] [Indexed: 08/04/2023]
Abstract
V2-glycan/apex broadly neutralizing antibodies (bnAbs) recognize a closed quaternary epitope of the HIV-1 envelope glycoprotein (Env). This closed structure is necessary to elicit apex antibodies and useful to guide the maturation of other bnAb classes. To compare antigens designed to maintain this conformation, we evaluated apex-specific responses in mice engrafted with a diverse repertoire of B cells expressing the HCDR3 of the apex bnAb VRC26.25. Engineered B cells affinity matured, guiding the improvement of VRC26.25 itself. We found that soluble Env (SOSIP) variants differed significantly in their ability to raise anti-apex responses. A transmembrane SOSIP (SOSIP-TM) delivered as an mRNA-lipid nanoparticle elicited more potent neutralizing responses than multimerized SOSIP proteins. Importantly, SOSIP-TM elicited neutralizing sera from B cells engineered with the predicted VRC26.25-HCDR3 progenitor, which also affinity matured. Our data show that HCDR3-edited B cells facilitate efficient in vivo comparisons of Env antigens and highlight the potential of an HCDR3-focused vaccine approach.
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Affiliation(s)
- Wenhui He
- Division of Infectious Disease, Boston Children's Hospital, Boston, MA 02115, USA; The Center for Integrated Solutions to Infectious Diseases, The Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA; Department of Immunology and Microbiology, UF Scripps Biomedical Research, Jupiter, FL 33458, USA
| | - Tianling Ou
- Division of Infectious Disease, Boston Children's Hospital, Boston, MA 02115, USA; The Center for Integrated Solutions to Infectious Diseases, The Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA; Department of Immunology and Microbiology, UF Scripps Biomedical Research, Jupiter, FL 33458, USA
| | - Nickolas Skamangas
- Division of Infectious Disease, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA; Department of Immunology and Microbiology, UF Scripps Biomedical Research, Jupiter, FL 33458, USA
| | - Charles C Bailey
- The Center for Integrated Solutions to Infectious Diseases, The Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Immunology and Microbiology, UF Scripps Biomedical Research, Jupiter, FL 33458, USA
| | - Naomi Bronkema
- Division of Infectious Disease, Boston Children's Hospital, Boston, MA 02115, USA; The Center for Integrated Solutions to Infectious Diseases, The Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Skaggs Graduate School, Scripps Research, La Jolla, CA 92037, USA
| | - Yan Guo
- Department of Immunology and Microbiology, UF Scripps Biomedical Research, Jupiter, FL 33458, USA
| | - Yiming Yin
- Division of Infectious Disease, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Valerie Kobzarenko
- Department of Computer Engineering and Sciences, Florida Institute of Technology, Melbourne, FL 32901, USA
| | - Xia Zhang
- Department of Immunology and Microbiology, UF Scripps Biomedical Research, Jupiter, FL 33458, USA
| | - Andi Pan
- Division of Infectious Disease, Boston Children's Hospital, Boston, MA 02115, USA; The Center for Integrated Solutions to Infectious Diseases, The Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Skaggs Graduate School, Scripps Research, La Jolla, CA 92037, USA
| | - Xin Liu
- Division of Infectious Disease, Boston Children's Hospital, Boston, MA 02115, USA; The Center for Integrated Solutions to Infectious Diseases, The Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Jinge Xu
- Division of Infectious Disease, Boston Children's Hospital, Boston, MA 02115, USA; The Center for Integrated Solutions to Infectious Diseases, The Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Lizhou Zhang
- Division of Infectious Disease, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA; Department of Immunology and Microbiology, UF Scripps Biomedical Research, Jupiter, FL 33458, USA
| | - Ava E Allwardt
- Division of Infectious Disease, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Debasis Mitra
- Department of Computer Engineering and Sciences, Florida Institute of Technology, Melbourne, FL 32901, USA
| | - Brian Quinlan
- Department of Immunology and Microbiology, UF Scripps Biomedical Research, Jupiter, FL 33458, USA
| | - Rogier W Sanders
- Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Hyeryun Choe
- Division of Infectious Disease, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Michael Farzan
- Division of Infectious Disease, Boston Children's Hospital, Boston, MA 02115, USA; The Center for Integrated Solutions to Infectious Diseases, The Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA; Skaggs Graduate School, Scripps Research, La Jolla, CA 92037, USA.
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4
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Ringe RP, Colin P, Ozorowski G, Allen JD, Yasmeen A, Seabright GE, Lee JH, Antanasijevic A, Rantalainen K, Ketas T, Moore JP, Ward AB, Crispin M, Klasse PJ. Glycan heterogeneity as a cause of the persistent fraction in HIV-1 neutralization. PLoS Pathog 2023; 19:e1011601. [PMID: 37903160 PMCID: PMC10635575 DOI: 10.1371/journal.ppat.1011601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 11/09/2023] [Accepted: 10/05/2023] [Indexed: 11/01/2023] Open
Abstract
Neutralizing antibodies (NAbs) to multiple epitopes on the HIV-1-envelope glycoprotein (Env) have been isolated from infected persons. The potency of NAbs is measured more often than the size of the persistent fraction of infectivity at maximum neutralization, which may also influence preventive efficacy of active or passive immunization and the therapeutic outcome of the latter. Many NAbs neutralize HIV-1 CZA97.012, a clone of a Clade-C isolate, to ~100%. But here NAb PGT151, directed to a fusion-peptide epitope, left a persistent fraction of 15%. NAb PGT145, ligating the Env-trimer apex, left no detectable persistent fraction. The divergence in persistent fractions was further analyzed by depletion of pseudoviral populations of the most PGT151- and PGT145-reactive virions. Thereby, neutralization by the non-depleting NAb increased, whereas neutralization by the depleting NAb decreased. Furthermore, depletion by PGT151 increased sensitivity to autologous neutralization by sera from rabbits immunized with soluble native-like CZA97.012 trimer: substantial persistent fractions were reduced. NAbs in these sera target epitopes comprising residue D411 at the V4-β19 transition in a defect of the glycan shield on CZA97.012 Env. NAb binding to affinity-fractionated soluble native-like CZA97.012 trimer differed commensurately with neutralization in analyses by ELISA and surface plasmon resonance. Glycan differences between PGT151- and PGT145-purified trimer fractions were then demonstrated by mass spectrometry, providing one explanation for the differential antigenicity. These differences were interpreted in relation to a new structure at 3.4-Å resolution of the soluble CZA97.012 trimer determined by cryo-electron microscopy. The trimer adopted a closed conformation, refuting apex opening as the cause of reduced PGT145 binding to the PGT151-purified form. The evidence suggests that differences in binding and neutralization after trimer purification or pseudovirus depletion with PGT145 or PGT151 are caused by variation in glycosylation, and that some glycan variants affect antigenicity through direct effects on antibody contacts, whereas others act allosterically.
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Affiliation(s)
- Rajesh P. Ringe
- Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, New York, New York, United States of America
| | - Philippe Colin
- Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, New York, New York, United States of America
| | - Gabriel Ozorowski
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, United States of America
| | - Joel D. Allen
- School of Biological Sciences, University of Southampton, Southampton, United Kingdom
| | - Anila Yasmeen
- Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, New York, New York, United States of America
| | - Gemma E. Seabright
- School of Biological Sciences, University of Southampton, Southampton, United Kingdom
| | - Jeong Hyun Lee
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, United States of America
| | - Aleksandar Antanasijevic
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, United States of America
| | - Kimmo Rantalainen
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, United States of America
| | - Thomas Ketas
- Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, New York, New York, United States of America
| | - John P. Moore
- Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, New York, New York, United States of America
| | - Andrew B. Ward
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, United States of America
| | - Max Crispin
- School of Biological Sciences, University of Southampton, Southampton, United Kingdom
| | - P. J. Klasse
- Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, New York, New York, United States of America
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5
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Margolin E, Allen JD, Verbeek M, Chapman R, Meyers A, van Diepen M, Ximba P, Motlou T, Moore PL, Woodward J, Strasser R, Crispin M, Williamson AL, Rybicki EP. Augmenting glycosylation-directed folding pathways enhances the fidelity of HIV Env immunogen production in plants. Biotechnol Bioeng 2022; 119:2919-2937. [PMID: 35781691 PMCID: PMC9544252 DOI: 10.1002/bit.28169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 06/23/2022] [Accepted: 06/27/2022] [Indexed: 11/25/2022]
Abstract
Heterologous glycoprotein production relies on host glycosylation-dependent folding. When the biosynthetic machinery differs from the usual expression host, there is scope to remodel the assembly pathway to enhance glycoprotein production. Here we explore the integration of chaperone coexpression with glyco-engineering to improve the production of a model HIV-1 envelope antigen. Calreticulin was coexpressed to support protein folding together with Leishmania major STT3D oligosaccharyltransferase, to improve glycan occupancy, RNA interference to suppress the formation of truncated glycans, and Nicotiana benthamiana plants lacking α1,3-fucosyltransferase and β1,2-xylosyltransferase was used as an expression host to prevent plant-specific complex N-glycans forming. This approach reduced the formation of undesired aggregates, which predominated in the absence of glyco-engineering. The resulting antigen also exhibited increased glycan occupancy, albeit to a slightly lower level than the equivalent mammalian cell-produced protein. The antigen was decorated almost exclusively with oligomannose glycans, which were less processed compared with the mammalian protein. Immunized rabbits developed comparable immune responses to the plant-produced and mammalian cell-derived antigens, including the induction of autologous neutralizing antibodies when the proteins were used to boost DNA and modified vaccinia Ankara virus-vectored vaccines. This study demonstrates that engineering glycosylation-directed folding offers a promising route to enhance the production of complex viral glycoproteins in plants.
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Affiliation(s)
- Emmanuel Margolin
- Department of Pathology, Division of Medical Virology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- Wellcome Trust Centre for Infectious Disease Research in Africa, University of Cape Town, Cape Town, South Africa
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- Biopharming Research Unit, Department of Molecular and Cell Biology, University of Cape Town, Cape Town, South Africa
| | - Joel D Allen
- School of Biological Sciences, University of Southampton, Southampton, UK
| | - Matthew Verbeek
- Biopharming Research Unit, Department of Molecular and Cell Biology, University of Cape Town, Cape Town, South Africa
| | - Ros Chapman
- Department of Pathology, Division of Medical Virology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Ann Meyers
- Biopharming Research Unit, Department of Molecular and Cell Biology, University of Cape Town, Cape Town, South Africa
| | - Michiel van Diepen
- Department of Pathology, Division of Medical Virology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Phindile Ximba
- Department of Pathology, Division of Medical Virology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Thopisang Motlou
- National Institute for Communicable Diseases of the National Health Laboratory Service, Centre for HIV and STIs, Johannesburg, South Africa
- MRC Antibody Immunity Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Penny L Moore
- National Institute for Communicable Diseases of the National Health Laboratory Service, Centre for HIV and STIs, Johannesburg, South Africa
- MRC Antibody Immunity Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu-Natal, Congella, Durban, South Africa
| | - Jeremy Woodward
- Department of Integrative Biomedical Sciences, University of Cape Town, Cape Town, South Africa
| | - Richard Strasser
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Max Crispin
- School of Biological Sciences, University of Southampton, Southampton, UK
| | - Anna-Lise Williamson
- Department of Pathology, Division of Medical Virology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- Wellcome Trust Centre for Infectious Disease Research in Africa, University of Cape Town, Cape Town, South Africa
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Edward P Rybicki
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- Biopharming Research Unit, Department of Molecular and Cell Biology, University of Cape Town, Cape Town, South Africa
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6
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Walker LM, Shiakolas AR, Venkat R, Liu ZA, Wall S, Raju N, Pilewski KA, Setliff I, Murji AA, Gillespie R, Makoah NA, Kanekiyo M, Connors M, Morris L, Georgiev IS. High-Throughput B Cell Epitope Determination by Next-Generation Sequencing. Front Immunol 2022; 13:855772. [PMID: 35401559 PMCID: PMC8984479 DOI: 10.3389/fimmu.2022.855772] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Accepted: 02/14/2022] [Indexed: 01/12/2023] Open
Abstract
Development of novel technologies for the discovery of human monoclonal antibodies has proven invaluable in the fight against infectious diseases. Among the diverse antibody repertoires elicited by infection or vaccination, often only rare antibodies targeting specific epitopes of interest are of potential therapeutic value. Current antibody discovery efforts are capable of identifying B cells specific for a given antigen; however, epitope specificity information is usually only obtained after subsequent monoclonal antibody production and characterization. Here we describe LIBRA-seq with epitope mapping, a next-generation sequencing technology that enables residue-level epitope determination for thousands of single B cells simultaneously. By utilizing an antigen panel of point mutants within the HIV-1 Env glycoprotein, we identified and confirmed antibodies targeting multiple sites of vulnerability on Env, including the CD4-binding site and the V3-glycan site. LIBRA-seq with epitope mapping is an efficient tool for high-throughput identification of antibodies against epitopes of interest on a given antigen target.
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Affiliation(s)
- Lauren M. Walker
- Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, TN, United States
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Andrea R. Shiakolas
- Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, TN, United States
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Rohit Venkat
- Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Zhaojing Ariel Liu
- Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Steven Wall
- Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, TN, United States
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Nagarajan Raju
- Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, TN, United States
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Kelsey A. Pilewski
- Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, TN, United States
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Ian Setliff
- Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Amyn A. Murji
- Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Rebecca Gillespie
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH), Bethesda, MD, United States
| | - Nigel A. Makoah
- Division of Virology, Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa
- National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg, South Africa
| | - Masaru Kanekiyo
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH), Bethesda, MD, United States
| | - Mark Connors
- National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH), Bethesda, MD, United States
| | - Lynn Morris
- National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg, South Africa
- Antibody Immunity Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu-Natal, Durban, South Africa
| | - Ivelin S. Georgiev
- Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, TN, United States
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, United States
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, TN, United States
- Department of Electrical Engineering and Computer Science, Vanderbilt University, Nashville, TN, United States
- Center for Structural Biology, Vanderbilt University, Nashville, TN, United States
- Program in Computational Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, United States
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7
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Schorcht A, Cottrell CA, Pugach P, Ringe RP, Han AX, Allen JD, van den Kerkhof TLGM, Seabright GE, Schermer EE, Ketas TJ, Burger JA, van Schooten J, LaBranche CC, Ozorowski G, de Val N, Bader DLV, Schuitemaker H, Russell CA, Montefiori DC, van Gils MJ, Crispin M, Klasse PJ, Ward AB, Moore JP, Sanders RW. The Glycan Hole Area of HIV-1 Envelope Trimers Contributes Prominently to the Induction of Autologous Neutralization. J Virol 2022; 96:e0155221. [PMID: 34669426 PMCID: PMC8754230 DOI: 10.1128/jvi.01552-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Accepted: 10/14/2021] [Indexed: 01/15/2023] Open
Abstract
The human immunodeficiency virus type 1 (HIV-1) trimeric envelope glycoprotein (Env) is heavily glycosylated, creating a dense glycan shield that protects the underlying peptidic surface from antibody recognition. The absence of conserved glycans, due to missing potential N-linked glycosylation sites (PNGS), can result in strain-specific, autologous neutralizing antibody (NAb) responses. Here, we sought to gain a deeper understanding of the autologous neutralization by introducing holes in the otherwise dense glycan shields of the AMC011 and AMC016 SOSIP trimers. Specifically, when we knocked out the N130 and N289 glycans, which are absent from the well-characterized B41 SOSIP trimer, we observed stronger autologous NAb responses. We also analyzed the highly variable NAb responses induced in rabbits by diverse SOSIP trimers from subtypes A, B, and C. Statistical analysis, using linear regression, revealed that the cumulative area exposed on a trimer by glycan holes correlates with the magnitude of the autologous NAb response. IMPORTANCE Forty years after the first description of HIV-1, the search for a protective vaccine is still ongoing. The sole target for antibodies that can neutralize the virus are the trimeric envelope glycoproteins (Envs) located on the viral surface. The glycoprotein surface is covered with glycans that shield off the underlying protein components from recognition by the immune system. However, the Env trimers of some viral strains have holes in the glycan shield. Immunized animals developed antibodies against such glycan holes. These antibodies are generally strain specific. Here, we sought to gain a deeper understanding of what drives these specific immune responses. First, we show that strain-specific neutralizing antibody responses can be increased by creating artificial holes in the glycan shield. Second, when studying a diverse set of Env trimers with different characteristics, we found that the surface area of the glycan holes contributes prominently to the induction of strain-specific neutralizing antibodies.
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Affiliation(s)
- Anna Schorcht
- Department of Medical Microbiology and Infection Prevention, Amsterdam Infection & Immunity Institute (AI&AII), Amsterdam UMC, Location Meibergdreef, University of Amsterdam, Amsterdam, The Netherlands
| | - Christopher A. Cottrell
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, USA
| | - Pavel Pugach
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, New York, USA
| | - Rajesh P. Ringe
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, New York, USA
| | - Alvin X. Han
- Laboratory of Applied Evolutionary Biology, Department of Medical Microbiology and Infection Prevention, Amsterdam Infection & Immunity Institute (AI&AII), Amsterdam UMC, Location Meibergdreef, University of Amsterdam, Amsterdam, The Netherlands
| | - Joel D. Allen
- Centre for Biological Sciences and Institute for Life Sciences, University of Southampton, Southampton, England, United Kingdom
| | - Tom L. G. M. van den Kerkhof
- Department of Medical Microbiology and Infection Prevention, Amsterdam Infection & Immunity Institute (AI&AII), Amsterdam UMC, Location Meibergdreef, University of Amsterdam, Amsterdam, The Netherlands
- Department of Experimental Immunology, Amsterdam Infection & Immunity Institute (AI&AII), Amsterdam UMC, Location Meibergdreef, University of Amsterdam, Amsterdam, The Netherlands
| | - Gemma E. Seabright
- Centre for Biological Sciences and Institute for Life Sciences, University of Southampton, Southampton, England, United Kingdom
| | - Edith E. Schermer
- Department of Medical Microbiology and Infection Prevention, Amsterdam Infection & Immunity Institute (AI&AII), Amsterdam UMC, Location Meibergdreef, University of Amsterdam, Amsterdam, The Netherlands
| | - Thomas J. Ketas
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, New York, USA
| | - Judith A. Burger
- Department of Medical Microbiology and Infection Prevention, Amsterdam Infection & Immunity Institute (AI&AII), Amsterdam UMC, Location Meibergdreef, University of Amsterdam, Amsterdam, The Netherlands
| | - Jelle van Schooten
- Department of Medical Microbiology and Infection Prevention, Amsterdam Infection & Immunity Institute (AI&AII), Amsterdam UMC, Location Meibergdreef, University of Amsterdam, Amsterdam, The Netherlands
| | - Celia C. LaBranche
- Department of Surgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Gabriel Ozorowski
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, USA
| | - Natalia de Val
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, USA
| | - Daniel L. V. Bader
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, USA
| | - Hanneke Schuitemaker
- Department of Experimental Immunology, Amsterdam Infection & Immunity Institute (AI&AII), Amsterdam UMC, Location Meibergdreef, University of Amsterdam, Amsterdam, The Netherlands
| | - Colin A. Russell
- Laboratory of Applied Evolutionary Biology, Department of Medical Microbiology and Infection Prevention, Amsterdam Infection & Immunity Institute (AI&AII), Amsterdam UMC, Location Meibergdreef, University of Amsterdam, Amsterdam, The Netherlands
| | - David C. Montefiori
- Department of Surgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Marit J. van Gils
- Department of Medical Microbiology and Infection Prevention, Amsterdam Infection & Immunity Institute (AI&AII), Amsterdam UMC, Location Meibergdreef, University of Amsterdam, Amsterdam, The Netherlands
| | - Max Crispin
- Centre for Biological Sciences and Institute for Life Sciences, University of Southampton, Southampton, England, United Kingdom
| | - P. J. Klasse
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, New York, USA
| | - Andrew B. Ward
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, USA
| | - John P. Moore
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, New York, USA
| | - Rogier W. Sanders
- Department of Medical Microbiology and Infection Prevention, Amsterdam Infection & Immunity Institute (AI&AII), Amsterdam UMC, Location Meibergdreef, University of Amsterdam, Amsterdam, The Netherlands
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, New York, USA
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8
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Zhang S, Wang K, Wang WL, Nguyen HT, Chen S, Lu M, Go EP, Ding H, Steinbock RT, Desaire H, Kappes JC, Sodroski J, Mao Y. Asymmetric Structures and Conformational Plasticity of the Uncleaved Full-Length Human Immunodeficiency Virus Envelope Glycoprotein Trimer. J Virol 2021; 95:e0052921. [PMID: 34549974 PMCID: PMC8610584 DOI: 10.1128/jvi.00529-21] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 09/06/2021] [Indexed: 11/20/2022] Open
Abstract
The functional human immunodeficiency virus (HIV-1) envelope glycoprotein (Env) trimer [(gp120/gp41)3] is produced by cleavage of a conformationally flexible gp160 precursor. gp160 cleavage or the binding of BMS-806, an entry inhibitor, stabilizes the pretriggered, "closed" (state 1) conformation recognized by rarely elicited broadly neutralizing antibodies. Poorly neutralizing antibodies (pNAbs) elicited at high titers during natural infection recognize more "open" Env conformations (states 2 and 3) induced by binding the receptor, CD4. We found that BMS-806 treatment and cross-linking decreased the exposure of pNAb epitopes on cell surface gp160; however, after detergent solubilization, cross-linked and BMS-806-treated gp160 sampled non-state-1 conformations that could be recognized by pNAbs. Cryo-electron microscopy of the purified BMS-806-bound gp160 revealed two hitherto unknown asymmetric trimer conformations, providing insights into the allosteric coupling between trimer opening and structural variation in the gp41 HR1N region. The individual protomer structures in the asymmetric gp160 trimers resemble those of other genetically modified or antibody-bound cleaved HIV-1 Env trimers, which have been suggested to assume state-2-like conformations. Asymmetry of the uncleaved Env potentially exposes surfaces of the trimer to pNAbs. To evaluate the effect of stabilizing a state-1-like conformation of the membrane Env precursor, we treated cells expressing wild-type HIV-1 Env with BMS-806. BMS-806 treatment decreased both gp160 cleavage and the addition of complex glycans, implying that gp160 conformational flexibility contributes to the efficiency of these processes. Selective pressure to maintain flexibility in the precursor of functional Env allows the uncleaved Env to sample asymmetric conformations that potentially skew host antibody responses toward pNAbs. IMPORTANCE The envelope glycoprotein (Env) trimers on the surface of human immunodeficiency virus (HIV-1) mediate the entry of the virus into host cells and serve as targets for neutralizing antibodies. The functional Env trimer is produced by cleavage of the gp160 precursor in the infected cell. We found that the HIV-1 Env precursor is highly plastic, allowing it to assume different asymmetric shapes. This conformational plasticity is potentially important for Env cleavage and proper modification by sugars. Having a flexible, asymmetric Env precursor that can misdirect host antibody responses without compromising virus infectivity would be an advantage for a persistent virus like HIV-1.
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Affiliation(s)
- Shijian Zhang
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA
| | - Kunyu Wang
- State Key Laboratory for Artificial Microstructures and Mesoscopic Physics, School of Physics, Center for Quantitative Biology, Peking University, Beijing, China
| | - Wei Li Wang
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
- State Key Laboratory for Artificial Microstructures and Mesoscopic Physics, School of Physics, Center for Quantitative Biology, Peking University, Beijing, China
- Intel Parallel Computing Center for Structural Biology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Hanh T. Nguyen
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA
| | - Shuobing Chen
- State Key Laboratory for Artificial Microstructures and Mesoscopic Physics, School of Physics, Center for Quantitative Biology, Peking University, Beijing, China
| | - Maolin Lu
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Eden P. Go
- Department of Chemistry, University of Kansas, Lawrence, Kansas, USA
| | - Haitao Ding
- Department of Medicine, University of Alabama at Birmingham, Alabama, USA
| | - Robert T. Steinbock
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
| | - Heather Desaire
- Department of Chemistry, University of Kansas, Lawrence, Kansas, USA
| | - John C. Kappes
- Department of Medicine, University of Alabama at Birmingham, Alabama, USA
- Birmingham Veterans Affairs Medical Center, Research Service, Birmingham, Alabama, USA
| | - Joseph Sodroski
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA
- Department of Immunology and Infectious Disease, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
| | - Youdong Mao
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
- State Key Laboratory for Artificial Microstructures and Mesoscopic Physics, School of Physics, Center for Quantitative Biology, Peking University, Beijing, China
- Intel Parallel Computing Center for Structural Biology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
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9
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Chapman R, van Diepen M, Douglass N, Galant S, Jaffer M, Margolin E, Ximba P, Hermanus T, Moore PL, Williamson AL. Assessment of an LSDV-Vectored Vaccine for Heterologous Prime-Boost Immunizations against HIV. Vaccines (Basel) 2021; 9:1281. [PMID: 34835214 PMCID: PMC8620012 DOI: 10.3390/vaccines9111281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 10/18/2021] [Accepted: 10/27/2021] [Indexed: 11/18/2022] Open
Abstract
The modest protective effects of the RV144 HIV-1 vaccine trial have prompted the further exploration of improved poxvirus vector systems that can yield better immune responses and protection. In this study, a recombinant lumpy skin disease virus (LSDV) expressing HIV-1 CAP256.SU gp150 (Env) and a subtype C mosaic Gag was constructed (LSDVGC5) and compared to the equivalent recombinant modified vaccinia Ankara (MVAGC5). In vitro characterization confirmed that cells infected with recombinant LSDV produced Gag virus-like particles containing Env, and that Env expressed on the surface of the cells infected with LSDV was in a native-like conformation. This candidate HIV-1 vaccine (L) was tested in a rabbit model using different heterologous vaccination regimens, in combination with DNA (D) and MVA (M) vectors expressing the equivalent HIV-1 antigens. The four different vaccination regimens (DDMMLL, DDMLML, DDLMLM, and DDLLMM) all elicited high titers of binding and Tier 1A neutralizing antibodies (NAbs), and some regimens induced Tier 1B NAbs. Furthermore, two rabbits in the DDLMLM group developed low levels of autologous Tier 2 NAbs. The humoral immune responses elicited against HIV-1 Env by the recombinant LSDVGC5 were comparable to those induced by MVAGC5.
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Affiliation(s)
- Ros Chapman
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Science, University of Cape Town, Cape Town 7925, South Africa; (M.v.D.); (N.D.); (S.G.); (E.M.); (P.X.); (A.-L.W.)
- Division of Medical Virology, Department of Pathology, University of Cape Town, Cape Town 7925, South Africa
| | - Michiel van Diepen
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Science, University of Cape Town, Cape Town 7925, South Africa; (M.v.D.); (N.D.); (S.G.); (E.M.); (P.X.); (A.-L.W.)
- Division of Medical Virology, Department of Pathology, University of Cape Town, Cape Town 7925, South Africa
| | - Nicola Douglass
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Science, University of Cape Town, Cape Town 7925, South Africa; (M.v.D.); (N.D.); (S.G.); (E.M.); (P.X.); (A.-L.W.)
- Division of Medical Virology, Department of Pathology, University of Cape Town, Cape Town 7925, South Africa
| | - Shireen Galant
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Science, University of Cape Town, Cape Town 7925, South Africa; (M.v.D.); (N.D.); (S.G.); (E.M.); (P.X.); (A.-L.W.)
- Division of Medical Virology, Department of Pathology, University of Cape Town, Cape Town 7925, South Africa
| | - Mohamed Jaffer
- Electron Microscope Unit, University of Cape Town, Rondebosch 7701, South Africa;
| | - Emmanuel Margolin
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Science, University of Cape Town, Cape Town 7925, South Africa; (M.v.D.); (N.D.); (S.G.); (E.M.); (P.X.); (A.-L.W.)
- Division of Medical Virology, Department of Pathology, University of Cape Town, Cape Town 7925, South Africa
| | - Phindile Ximba
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Science, University of Cape Town, Cape Town 7925, South Africa; (M.v.D.); (N.D.); (S.G.); (E.M.); (P.X.); (A.-L.W.)
- Division of Medical Virology, Department of Pathology, University of Cape Town, Cape Town 7925, South Africa
| | - Tandile Hermanus
- Centre for HIV and STIs, National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg 2131, South Africa; (T.H.); (P.L.M.)
- Antibody Immunity Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2050, South Africa
| | - Penny L. Moore
- Centre for HIV and STIs, National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg 2131, South Africa; (T.H.); (P.L.M.)
- Antibody Immunity Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2050, South Africa
- Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu-Natal, Congella, Durban 4013, South Africa
| | - Anna-Lise Williamson
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Science, University of Cape Town, Cape Town 7925, South Africa; (M.v.D.); (N.D.); (S.G.); (E.M.); (P.X.); (A.-L.W.)
- Division of Medical Virology, Department of Pathology, University of Cape Town, Cape Town 7925, South Africa
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10
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Derking R, Sanders RW. Structure-guided envelope trimer design in HIV-1 vaccine development: a narrative review. J Int AIDS Soc 2021; 24 Suppl 7:e25797. [PMID: 34806305 PMCID: PMC8606863 DOI: 10.1002/jia2.25797] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Accepted: 08/03/2021] [Indexed: 12/13/2022] Open
Abstract
INTRODUCTION The development of a human immunodeficiency virus 1 (HIV-1) vaccine remains a formidable challenge. An effective vaccine likely requires the induction of broadly neutralizing antibodies (bNAbs), which likely involves the use of native-like HIV-1 envelope (Env) trimers at some or all stages of vaccination. Development of such trimers has been very difficult, but much progress has been made in the past decade, starting with the BG505 SOSIP trimer, elucidation of its atomic structure and implementing subsequent design iterations. This progress facilitated understanding the weaknesses of the Env trimer, fuelled structure-guided HIV-1 vaccine design and assisted in the development of new vaccine designs. This review summarizes the relevant literature focusing on studies using structural biology to reveal and define HIV-1 Env sites of vulnerability; to improve Env trimers, by creating more stable versions; understanding antibody responses in preclinical vaccination studies at the atomic level; understanding the glycan shield; and to improve "on-target" antibody responses versus "off-target" responses. METHODS The authors conducted a narrative review of recently published articles that made a major contribution to HIV-1 structural biology and vaccine design efforts between the years 2000 and 2021. DISCUSSION The field of structural biology is evolving at an unprecedented pace, where cryo-electron microscopy (cryo-EM) and X-ray crystallography provide complementary information. Resolving protein structures is necessary for defining which Env surfaces are accessible for the immune system and can be targeted by neutralizing antibodies. Recently developed techniques, such as electron microscopy-based polyclonal epitope mapping (EMPEM) are revolutionizing the way we are analysing immune responses and shed light on the immunodominant targets on new vaccine immunogens. Such information accelerates iterative vaccine design; for example, by reducing undesirable off-target responses, while improving immunogens to drive the more desirable on-target responses. CONCLUSIONS Resolving high-resolution structures of the HIV-1 Env trimer was instrumental in understanding and improving recombinant HIV-1 Env trimers that mimic the structure of viral HIV-1 Env spikes. Newly emerging techniques in structural biology are aiding vaccine design efforts and improving immunogens. The role of structural biology in HIV-1 vaccine design has indeed become very prominent and is unlikely to diminish any time soon.
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Affiliation(s)
- Ronald Derking
- Department of Medical MicrobiologyAmsterdam Infection & Immunity InstituteAmsterdam UMC, AMCUniversity of AmsterdamAmsterdamThe Netherlands
| | - Rogier W. Sanders
- Department of Medical MicrobiologyAmsterdam Infection & Immunity InstituteAmsterdam UMC, AMCUniversity of AmsterdamAmsterdamThe Netherlands
- Department of Microbiology and ImmunologyWeill Medical College of Cornell UniversityNew YorkNew YorkUSA
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11
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James EI, Murphree TA, Vorauer C, Engen JR, Guttman M. Advances in Hydrogen/Deuterium Exchange Mass Spectrometry and the Pursuit of Challenging Biological Systems. Chem Rev 2021; 122:7562-7623. [PMID: 34493042 PMCID: PMC9053315 DOI: 10.1021/acs.chemrev.1c00279] [Citation(s) in RCA: 101] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
![]()
Solution-phase hydrogen/deuterium
exchange (HDX) coupled to mass
spectrometry (MS) is a widespread tool for structural analysis across
academia and the biopharmaceutical industry. By monitoring the exchangeability
of backbone amide protons, HDX-MS can reveal information about higher-order
structure and dynamics throughout a protein, can track protein folding
pathways, map interaction sites, and assess conformational states
of protein samples. The combination of the versatility of the hydrogen/deuterium
exchange reaction with the sensitivity of mass spectrometry has enabled
the study of extremely challenging protein systems, some of which
cannot be suitably studied using other techniques. Improvements over
the past three decades have continually increased throughput, robustness,
and expanded the limits of what is feasible for HDX-MS investigations.
To provide an overview for researchers seeking to utilize and derive
the most from HDX-MS for protein structural analysis, we summarize
the fundamental principles, basic methodology, strengths and weaknesses,
and the established applications of HDX-MS while highlighting new
developments and applications.
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Affiliation(s)
- Ellie I James
- Department of Medicinal Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Taylor A Murphree
- Department of Medicinal Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Clint Vorauer
- Department of Medicinal Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - John R Engen
- Department of Chemistry & Chemical Biology, Northeastern University, Boston, Massachusetts 02115, United States
| | - Miklos Guttman
- Department of Medicinal Chemistry, University of Washington, Seattle, Washington 98195, United States
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12
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Velarde de la Cruz E, Wang L, Bose D, Gangadhara S, Wilson RL, Amara RR, Kozlowski PA, Aldovini A. Oral Vaccination Approaches for Anti-SHIV Immunity. Front Immunol 2021; 12:702705. [PMID: 34234789 PMCID: PMC8256843 DOI: 10.3389/fimmu.2021.702705] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 06/04/2021] [Indexed: 11/16/2022] Open
Abstract
We modified a Sabin Oral Poliovirus Vaccine (OPV) vector to permit secretion of the antigens of interest with the goal of improving anti-HIV Env humoral responses in a SHIV mucosal immunization composed of DNA and recombinant OPVs. We evaluated stimulation of systemic and mucosal cell-mediated and humoral immunity in Rhesus macaques by two regimens, both involving a prime with a SHIVBG505 DNA construct producing non-infectious particles formulated in lipid nanoparticles, administered in the oral cavity, and two different viral vector boostings, administered in the oral cavity and intestinally. Group 1 was boosted with rMVA-SHIVBG505, expressing SIV Gag/Pol and HIVBG505 Env. Group 2 was boosted with a SHIVBG505-OPV vaccine including a non-secreting SIVmac239CA-p6-OPV, expressing Gag CA, NC and p6 proteins, and a HIVBG505C1-V2-OPV, secreting the C1-V2 fragment of HIV EnvBG505, recognized by the broadly neutralizing antibody PG16. A time course analysis of anti-SHIV Gag and Env CD4+ and CD8+ T-cell responses in PBMC and in lymph node, rectal, and vaginal MNC was carried out. Both regimens stimulated significant cell-mediated responses in all compartments, with SHIVBG505-OPV immunization stimulating more significant levels of responses than rMVA- SHIVBG505. Boolean analysis of these responses revealed predominantly monofunctional responses with multifunctional responses also present in all tissues. Stimulation of antibody responses was disappointing in both groups with negative anti-SHIV IgG in plasma, and IgA in salivary, rectal and vaginal secretions being restricted to a few animals. After repeated rectal challenge with SHIVBG505, two Group 1 animals remained uninfected at challenge termination. No significant differences were observed in post-infection viral loads between groups. After the acute phase decline, CD4+ T cell percentages returned to normal levels in vaccinated as well as control animals. However, when compared to controls, vaccinate groups had more significant preservation of PBMC and rectal MNC Th17/Treg ratios, considered the strongest surrogate marker of progression to AIDS. We conclude that the vaccine platforms used in this study are insufficient to stimulate significant humoral immunity at the tested doses and schedule but sufficient to stimulate significant mucosal and systemic cell-mediated immunity, impacting the preservation of key Th17 CD4+ T cells in blood and rectal mucosa.
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Affiliation(s)
- Erandi Velarde de la Cruz
- Department of Medicine, Boston Children’s Hospital, Boston, MA, United States
- Department of Pediatrics, Harvard Medical School, Boston, MA, United States
| | - Lingyun Wang
- Department of Medicine, Boston Children’s Hospital, Boston, MA, United States
- Department of Pediatrics, Harvard Medical School, Boston, MA, United States
| | - Deepanwita Bose
- Department of Medicine, Boston Children’s Hospital, Boston, MA, United States
- Department of Pediatrics, Harvard Medical School, Boston, MA, United States
| | - Sailaja Gangadhara
- Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA, United States
- Department of Microbiology and Immunology, Emory School of Medicine, Emory University, Atlanta, GA, United States
| | - Robert L. Wilson
- Department of Microbiology, Immunology and Parasitology, Louisiana State University Health Sciences Center, New Orleans, LA, United States
| | - Rama R. Amara
- Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA, United States
- Department of Microbiology and Immunology, Emory School of Medicine, Emory University, Atlanta, GA, United States
| | - Pamela A. Kozlowski
- Department of Microbiology, Immunology and Parasitology, Louisiana State University Health Sciences Center, New Orleans, LA, United States
| | - Anna Aldovini
- Department of Medicine, Boston Children’s Hospital, Boston, MA, United States
- Department of Pediatrics, Harvard Medical School, Boston, MA, United States
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13
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Membrane Env Liposomes Facilitate Immunization with Multivalent Full-Length HIV Spikes. J Virol 2021; 95:e0000521. [PMID: 33883221 DOI: 10.1128/jvi.00005-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
A major goal of HIV vaccine design is to elicit broadly neutralizing antibodies (bNAbs). Such bNAbs target HIV's trimeric, membrane-embedded envelope glycoprotein spikes (mEnv). Soluble Env (sEnv) trimers have been used as vaccines, but engineering sEnvs for stability, multivalency, and desired antigenicity is problematic and deletes key neutralizing epitopes on glycoprotein 41 (gp41) while creating neoepitopes that elicit unwanted antibodies. Meanwhile, multivalent mEnv vaccines are challenging to develop due to trimer instability and low mEnv copy number amid other extraneous proteins on virus-like particles. Here, we describe a multivalent mEnv vaccine platform that does not require protein engineering or extraneous proteins. mEnv trimers were fixed, purified, and combined with naked liposomes in mild detergent. On removal of detergent, mEnv spikes were observed embedded in liposome particles (mean diameter, 133 nm) in correct orientation. These particles were recognized by HIV bNAbs and not non-NAbs and are designated mEnv liposomes (MELs). Following a sequential immunization scheme in rabbits, MELs elicited antibodies that neutralized tier 2 HIV isolates. Analysis of serum antibody specificities, including those to epitopes involving a missing conserved N-glycosylation site at position 197 near the CD4 binding site on two of the immunogens, provides clues on how NAb responses can be improved with modified immunogens. In sum, MELs are a biochemically defined platform that enables rational immunization strategies to elicit HIV bNAbs using multimerized mEnv. IMPORTANCE A vaccine that induced broadly neutralizing antibodies against HIV would likely end the AIDS pandemic. Such antibodies target membrane-embedded envelope glycoprotein spikes (mEnv) that HIV uses to enter cells. Due to HIV Env's low expression and instability, soluble stabilized Env trimers have been used as vaccine candidates, but these have an altered base that disrupts targets of HIV broadly neutralizing antibodies that bind near the membrane and are not available for all HIV isolates. Here, we describe membrane Env liposomes (MELs) that display a multivalent array of stable mEnvs on liposome particles. MELs showed the expected antibody recognition properties, including targeting parts of mEnv missing on soluble Envs. Immunization with MELs elicited antibodies that neutralized diverse HIV isolates. The MEL platform facilitates vaccine development with potentially any HIV Env at high valency, and a similar approach may be useful for eliciting antibodies to membrane-embedded targets of therapeutic interest.
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The Versatile Manipulations of Self-Assembled Proteins in Vaccine Design. Int J Mol Sci 2021; 22:ijms22041934. [PMID: 33669238 PMCID: PMC7919822 DOI: 10.3390/ijms22041934] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 02/06/2021] [Accepted: 02/11/2021] [Indexed: 12/16/2022] Open
Abstract
Protein assemblies provide unique structural features which make them useful as carrier molecules in biomedical and chemical science. Protein assemblies can accommodate a variety of organic, inorganic and biological molecules such as small proteins and peptides and have been used in development of subunit vaccines via display parts of viral pathogens or antigens. Such subunit vaccines are much safer than traditional vaccines based on inactivated pathogens which are more likely to produce side-effects. Therefore, to tackle a pandemic and rapidly produce safer and more effective subunit vaccines based on protein assemblies, it is necessary to understand the basic structural features which drive protein self-assembly and functionalization of portions of pathogens. This review highlights recent developments and future perspectives in production of non-viral protein assemblies with essential structural features of subunit vaccines.
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15
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Ozorowski G, Torres JL, Santos-Martins D, Forli S, Ward AB. A Strain-Specific Inhibitor of Receptor-Bound HIV-1 Targets a Pocket near the Fusion Peptide. Cell Rep 2020; 33:108428. [PMID: 33238117 PMCID: PMC7701285 DOI: 10.1016/j.celrep.2020.108428] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 10/07/2020] [Accepted: 11/03/2020] [Indexed: 01/18/2023] Open
Abstract
Disruption of viral fusion represents a viable, albeit under-explored, target for HIV therapeutics. Here, while studying the receptor-bound envelope glycoprotein conformation by cryoelectron microscopy (cryo-EM), we identify a pocket near the base of the trimer containing a bound detergent molecule and perform in silico drug screening by using a library of drug-like and commercially available molecules. After down-selection, we solve cryo-EM structures that validate the binding of two small molecule hits in very similar manners to the predicted binding poses, including interactions with aromatic residues within the fusion peptide. One of the molecules demonstrates low micromolar inhibition of the autologous virus by using a very rare phenylalanine in the fusion peptide and stabilizing the surrounding region. This work demonstrates that small molecules can target the fusion process, providing an additional target for anti-HIV therapeutics, and highlights the need to explore how fusion peptide sequence variations affect receptor-mediated conformational states across diverse HIV strains.
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Affiliation(s)
- Gabriel Ozorowski
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA; Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, International AIDS Vaccine Initiative Neutralizing Antibody Center, and Collaboration for AIDS Vaccine Discovery, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Jonathan L Torres
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA; Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, International AIDS Vaccine Initiative Neutralizing Antibody Center, and Collaboration for AIDS Vaccine Discovery, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Diogo Santos-Martins
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Stefano Forli
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
| | - Andrew B Ward
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA; Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, International AIDS Vaccine Initiative Neutralizing Antibody Center, and Collaboration for AIDS Vaccine Discovery, The Scripps Research Institute, La Jolla, CA 92037, USA.
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16
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Das S, Kumar R, Ahmed S, Parray HA, Samal S. Efficiently cleaved HIV-1 envelopes: can they be important for vaccine immunogen development? Ther Adv Vaccines Immunother 2020; 8:2515135520957763. [PMID: 33103053 PMCID: PMC7549152 DOI: 10.1177/2515135520957763] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 08/17/2020] [Indexed: 12/31/2022] Open
Abstract
The enormous diversity of HIV-1 is a significant impediment in selecting envelopes (Envs) that can be suitable for designing vaccine immunogens. While tremendous progress has been made in developing soluble, trimeric, native-like Env proteins, those that have elicited neutralizing antibodies (Abs) in animal models are relatively few. A strategy of selecting naturally occurring Envs suitable for immunogen design by studying the correlation between efficient cleavage on the cell surface and their selective binding to broadly neutralizing Abs (bNAbs) and not to non-neutralizing Abs (non-NAbs), properties essential in immunogens, may be useful. Here we discuss some of the challenges of developing an efficacious HIV-1 vaccine and the work done in generating soluble immunogens. We also discuss the study of naturally occurring, membrane-bound, efficiently cleaved (naturally more sensitive to furin) Envs and how they may positively add to the repertoire of HIV-1 Envs that can be used for vaccine immunogen design. However, even with such Envs, the challenges of developing well-folded, native-like trimers as soluble proteins or using other immunogen strategies such as virus-like particles with desirable antigenic properties remain, and are formidable. In spite of the progress that has been made in the HIV-1 vaccine field, an immunogen that elicits neutralizing Abs with significant breadth and potency in vaccines has still not been developed. Efficiently cleaved Envs may increase the number of available Envs suitable for immunogen design and should be studied further.
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Affiliation(s)
- Supratik Das
- THSTI-IAVI HIV Vaccine Design Program,
Translational Health Science and Technology Institute, NCR Biotech Science
Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, PO Box #04, Faridabad,
Haryana 121001, India
| | - Rajesh Kumar
- Translational Health Science and Technology
Institute, NCR Biotech Science Cluster, Faridabad, Haryana, India
| | - Shubbir Ahmed
- Translational Health Science and Technology
Institute, NCR Biotech Science Cluster, Faridabad, Haryana, India
| | - Hilal Ahmad Parray
- Translational Health Science and Technology
Institute, NCR Biotech Science Cluster, Faridabad, Haryana, India
| | - Sweety Samal
- Translational Health Science and Technology
Institute, NCR Biotech Science Cluster, Faridabad, Haryana, India
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17
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González-Feliciano JA, Akamine P, Capó-Vélez CM, Delgado-Vélez M, Dussupt V, Krebs SJ, Wojna V, Polonis VR, Baerga-Ortiz A, Lasalde-Dominicci JA. A recombinant gp145 Env glycoprotein from HIV-1 expressed in two different cell lines: Effects on glycosylation and antigenicity. PLoS One 2020; 15:e0231679. [PMID: 32559193 PMCID: PMC7304579 DOI: 10.1371/journal.pone.0231679] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 06/04/2020] [Indexed: 11/18/2022] Open
Abstract
The envelope glycoprotein (Env) of the human immunodeficiency virus (HIV), has been the primary target for the development of a protective vaccine against infection. The extensive N-linked glycosylation on Env is an important consideration as it may affect efficacy, stability, and expression yields. The expression host has been shown to influence the extent and type of glycosylation that decorates the protein target. Here, we report the glycosylation profile of the candidate subtype C immunogen CO6980v0c22 gp145, which is currently in Phase I clinical trials, produced in two different host cells: CHO-K1 and Expi293F. The amino acid sequence for both glycoproteins was confirmed to be identical by peptide mass fingerprinting. However, the isoelectric point of the proteins differed; 4.5–5.5 and 6.0–7.0 for gp145 produced in CHO-K1 and Expi293F, respectively. These differences in pI were eliminated by enzymatic treatment with sialidase, indicating a large difference in the incorporation of sialic acid between hosts. This dramatic difference in the number of sialylated glycans between hosts was confirmed by analysis of PNGase F-released glycans using MALDI-ToF MS. These differences in glycosylation, however, did not greatly translate into differences in antibody recognition. Biosensor assays showed that gp145 produced in CHO-K1 had similar affinity toward the broadly neutralizing antibodies, 2G12 and PG16, as the gp145 produced in Expi293F. Additionally, both immunogens showed the same reactivity against plasma of HIV-infected patients. Taken together, these results support the notion that there are sizeable differences in the glycosylation of Env depending on the expression host. How these differences translate to vaccine efficacy remains unknown.
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Affiliation(s)
| | - Pearl Akamine
- Molecular Sciences Research Center Inc., University of Puerto Rico, San Juan, Puerto Rico
| | - Coral M. Capó-Vélez
- Molecular Sciences Research Center Inc., University of Puerto Rico, San Juan, Puerto Rico
| | - Manuel Delgado-Vélez
- Molecular Sciences Research Center Inc., University of Puerto Rico, San Juan, Puerto Rico
| | - Vincent Dussupt
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, Maryland, United States of America
| | - Shelly J. Krebs
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, Maryland, United States of America
| | - Valerie Wojna
- Division of Neurology, Internal Medicine Department and NeuroHIV Research Program, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico
| | - Victoria R. Polonis
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Abel Baerga-Ortiz
- Molecular Sciences Research Center Inc., University of Puerto Rico, San Juan, Puerto Rico
- Department of Biochemistry, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico
- * E-mail: (ABO); (JALD)
| | - José A. Lasalde-Dominicci
- Molecular Sciences Research Center Inc., University of Puerto Rico, San Juan, Puerto Rico
- Department of Biology, University of Puerto Rico, Rio Piedras Campus, San Juan, Puerto Rico
- * E-mail: (ABO); (JALD)
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18
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Bruxelle JF, Kirilenko T, Qureshi Q, Lu N, Trattnig N, Kosma P, Pantophlet R. Serum alpha-mannosidase as an additional barrier to eliciting oligomannose-specific HIV-1-neutralizing antibodies. Sci Rep 2020; 10:7582. [PMID: 32371950 PMCID: PMC7200719 DOI: 10.1038/s41598-020-64500-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 04/15/2020] [Indexed: 01/04/2023] Open
Abstract
Oligomannose-type glycans on HIV-1 gp120 form a patch that is targeted by several broadly neutralizing antibodies (bnAbs) and that therefore is of interest to vaccine design. However, attempts to elicit similar oligomannose-specific bnAbs by immunizing with oligomannosidic glycoconjugates have only been modestly successful so far. A common assumption is that eliciting oligomannose-specific bnAbs is hindered by B cell tolerance, resulting from the presented oligomannosides being sensed as self molecules. Here, we present data, along with existing scientific evidence, supporting an additional, or perhaps alternate, explanation: serum mannosidase trimming of the presented oligomannosides in vivo. Mannosidase trimming lessens the likelihood of eliciting antibodies with capacity to bind full-sized oligomannose, which typifies the binding mode of existing bnAbs to the oligomannose patch. The rapidity of the observed trimming suggests the need for immunization strategies and/or synthetic glycosides that readily avoid or resist mannosidase trimming upon immunization and can overcome possible tolerance restrictions.
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Affiliation(s)
- Jean-François Bruxelle
- Faculty of Health Sciences, Simon Fraser University, Burnaby, British Columbia, V5A1S6, Canada
| | - Tess Kirilenko
- Faculty of Health Sciences, Simon Fraser University, Burnaby, British Columbia, V5A1S6, Canada
- AbCellera Biologics Inc., Vancouver, British Columbia, Canada
| | - Quratulain Qureshi
- Department of Molecular Biology & Biochemistry, Simon Fraser University, Burnaby, British Columbia, V5A1S6, Canada
| | - Naiomi Lu
- Faculty of Health Sciences, Simon Fraser University, Burnaby, British Columbia, V5A1S6, Canada
| | - Nino Trattnig
- Department of Chemistry, University of Natural Resources and Life Sciences, Vienna, A-1190, Austria
- Department of Chemical Biology and Drug Discovery, Utrecht University, Utrecht, The Netherlands
| | - Paul Kosma
- Department of Chemistry, University of Natural Resources and Life Sciences, Vienna, A-1190, Austria
| | - Ralph Pantophlet
- Faculty of Health Sciences, Simon Fraser University, Burnaby, British Columbia, V5A1S6, Canada.
- Department of Molecular Biology & Biochemistry, Simon Fraser University, Burnaby, British Columbia, V5A1S6, Canada.
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19
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Ximba P, Chapman R, Meyers AE, Margolin E, van Diepen MT, Williamson AL, Rybicki EP. Characterization and Immunogenicity of HIV Envelope gp140 Zera ® Tagged Antigens. Front Bioeng Biotechnol 2020; 8:321. [PMID: 32328488 PMCID: PMC7160593 DOI: 10.3389/fbioe.2020.00321] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 03/24/2020] [Indexed: 11/13/2022] Open
Abstract
HIV-1 envelope glycoprotein (Env) remains the most relevant target for the elicitation of functional antibodies to HIV by vaccination. However, soluble Env antigens often do not elicit the desired immune responses. Delivering subunit antigens on particulate nanoparticles is an established approach to improve their immunogenicity. In this study the sequence encoding Zera®, a proline-rich domain derived from the γ-zein storage protein, was fused to either the C- or N-terminus of the superinfecting HIV-1 CAP256 gp140 envelope: Zera® generally induces the formation of protein bodies (PBs), which can significantly improve both the immunogenicity and yields of the partner protein. The expression of gp140-Zera® and Zera®-gp140 (N- and C-terminal fusions respectively) in mammalian cells was confirmed by western blot analysis and immunostaining. However, isopycnic ultracentrifugation showed that neither gp140-Zera® nor Zera®-gp140 accumulated in characteristic electron-dense PBs. gp140-Zera® elicited higher binding antibody titers in rabbits to autologous gp140 and V1V2 scaffold than Zera®-gp140. Rabbit anti-gp140-Zera® sera also had significantly higher Tier 1A neutralizing antibody titers than anti-Zera®-gp140 sera. Neither gp140-Zera® nor Zera®-gp140-specific sera neutralized Tier 1B or autologous Tier 2 viruses. These results showed that HIV-1 gp140 tagged with Zera® at either the N- or C-termini elicited high titers of gp140 and V1V2 binding antibodies, and low levels of Tier 1 neutralizing antibodies in rabbits.
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Affiliation(s)
- Phindile Ximba
- Division of Medical Virology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.,Biopharming Research Unit, Department of Molecular and Cell Biology, University of Cape Town, Cape Town, South Africa.,Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Rosamund Chapman
- Division of Medical Virology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.,Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Ann E Meyers
- Biopharming Research Unit, Department of Molecular and Cell Biology, University of Cape Town, Cape Town, South Africa
| | - Emmanuel Margolin
- Division of Medical Virology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.,Biopharming Research Unit, Department of Molecular and Cell Biology, University of Cape Town, Cape Town, South Africa.,Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Michiel T van Diepen
- Division of Medical Virology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.,Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Anna-Lise Williamson
- Division of Medical Virology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.,Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Edward P Rybicki
- Biopharming Research Unit, Department of Molecular and Cell Biology, University of Cape Town, Cape Town, South Africa.,Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
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20
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Sharma VK, Sharma I, Glick J. The expanding role of mass spectrometry in the field of vaccine development. MASS SPECTROMETRY REVIEWS 2020; 39:83-104. [PMID: 29852530 PMCID: PMC7027533 DOI: 10.1002/mas.21571] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 04/30/2018] [Indexed: 05/09/2023]
Abstract
Biological mass spectrometry has evolved as a core analytical technology in the last decade mainly because of its unparalleled ability to perform qualitative as well as quantitative profiling of enormously complex biological samples with high mass accuracy, sensitivity, selectivity and specificity. Mass spectrometry-based techniques are also routinely used to assess glycosylation and other post-translational modifications, disulfide bond linkage, and scrambling as well as for the detection of host cell protein contaminants in the field of biopharmaceuticals. The role of mass spectrometry in vaccine development has been very limited but is now expanding as the landscape of global vaccine development is shifting towards the development of recombinant vaccines. In this review, the role of mass spectrometry in vaccine development is presented, some of the ongoing efforts to develop vaccines for diseases with global unmet medical need are discussed and the regulatory challenges of implementing mass spectrometry techniques in a quality control laboratory setting are highlighted.
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Affiliation(s)
| | - Ity Sharma
- Independent CMC ConsultantParamusNew Jersey
| | - James Glick
- Novartis Institutes for BioMedical ResearchEast HanoverNew Jersey
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21
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Neutralizing Antibody Induction by HIV-1 Envelope Glycoprotein SOSIP Trimers on Iron Oxide Nanoparticles May Be Impaired by Mannose Binding Lectin. J Virol 2020; 94:JVI.01883-19. [PMID: 31852794 PMCID: PMC7158715 DOI: 10.1128/jvi.01883-19] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 12/12/2019] [Indexed: 01/23/2023] Open
Abstract
We covalently attached human immunodeficiency virus type 1 (HIV-1) Env SOSIP trimers to iron oxide nanoparticles (IO-NPs) to create a particulate immunogen for neutralizing antibody (NAb) induction. The attached trimers, ∼20 per particle, retained native-like antigenicity, judged by reactivity with NAbs and non-NAbs. Bivalent (BG505 and B41) trimer IO-NPs were made, as were IO-NPs displaying B41 trimers carrying a PADRE T-cell helper epitope (TCHE). We immunized mice with B41 soluble or IO-NP trimers after PADRE peptide priming. After two immunizations, IO-NP presentation and the TCHE tag independently and substantially increased anti-trimer antibody responses, but titer differences waned after two further doses. Notable and unexpected findings were that autologous NAbs to the N289 glycan hole epitope were consistently induced in mice given soluble but not IO-NP trimers. Various recombinant mannose binding lectins (MBLs) and MBLs in sera of both murine and human origin bound to soluble and IO-NP trimers. MBL binding occluded the autologous NAb epitope on the B41 IO-NP trimers, which may contribute to its poor immunogenicity. The exposure of a subset of broadly active NAb epitopes was also impaired by MBL binding, which could have substantial implications for the utility of trimer-bearing nanoparticles in general and perhaps also for soluble Env proteins.IMPORTANCE Recombinant trimeric SOSIP proteins are vaccine components intended to induce neutralizing antibodies (NAbs) that prevent cells from infection by human immunodeficiency virus type 1 (HIV-1). A way to increase the strength of antibody responses to these proteins is to present them on the surface of nanoparticles (NPs). We chemically attached about 20 SOSIP trimers to NPs made of iron oxide (IO). The resulting IO-NP trimers had appropriate properties when we studied them in the laboratory but, unexpectedly, were less able to induce NAbs than nonattached trimers when used to immunize mice. We found that mannose binding lectins, proteins naturally present in the serum of mice and other animals, bound strongly to the soluble and IO-NP trimers, blocking access to antibody epitopes in a way that may impede the development of NAb responses. These findings should influence how trimer-bearing NPs of various designs are made and used.
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22
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Matchett WE, Malewana GBR, Mudrick H, Medlyn MJ, Barry MA. Genetic Adjuvants in Replicating Single-Cycle Adenovirus Vectors Amplify Systemic and Mucosal Immune Responses against HIV-1 Envelope. Vaccines (Basel) 2020; 8:E64. [PMID: 32024265 PMCID: PMC7158672 DOI: 10.3390/vaccines8010064] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 01/28/2020] [Accepted: 01/30/2020] [Indexed: 12/22/2022] Open
Abstract
Most infections occur at mucosal surfaces. Providing a barrier of protection at these surfaces may be a useful strategy to combat the earliest events in infection when there are relatively few pathogens to address. The majority of vaccines are delivered systemically by the intramuscular (IM) route. While IM vaccination can drive mucosal immune responses, mucosal immunization at intranasal (IN) or oral sites can lead to better immune responses at mucosal sites of viral entry. In macaques, IN immunization with replicating single-cycle adenovirus (SC-Ads) and protein boosts generated favorable mucosal immune responses. However, there was an apparent "distance effect" in generating mucosal immune responses. IN immunization generated antibodies against HIV envelope (env) nearby in the saliva, but weaker responses in samples collected from the distant vaginal samples. To improve on this, we tested here if SC-Ads expressing genetic adjuvants could be used to amplify antibody responses in distant vaginal samples when they are codelivered with SC-Ads expressing clade C HIV env immunogen. SC-Ads env 1157 was coadministered with SC-Ads expressing 4-1BBL, granulocyte macrophage colony-stimulating factor (GMCSF), IL-21, or Clostridoides difficile (C. diff.) toxin fragments by IN or IM routes. These data show that vaginal antibody responses were markedly amplified after a single immunization by the IN or IM routes, with SC-Ad expressing HIV env if this vaccine is complemented with SC-Ads expressing genetic adjuvants. Furthermore, the site and combination of adjuvants appear to "tune" these antibody responses towards an IgA or IgG isotype bias. Boosting these priming SC-Ad responses with another SC-Ad or with SOSIP native-like env proteins markedly amplifies env antibody levels in vaginal washes. Together, this data may be useful in informing the choice of route of delivery adenovirus and peptide vaccines against HIV-1.
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Affiliation(s)
- William E. Matchett
- Virology and Gene Therapy (VGT) Graduate Program, Mayo Clinic, Rochester, MN 55905, USA;
| | | | - Haley Mudrick
- Molecular Pharmacology and Experimental Therapeutics (MPET) Graduate Program, Mayo Clinic, Rochester, MN 55905, USA;
| | | | - Michael A. Barry
- Department of Internal Medicine, Division of Infectious Diseases, Mayo Clinic, Rochester, MN 55905, USA
- Department of Immunology, Mayo Clinic, Rochester, MN 55905, USA
- Department of Molecular Medicine, Mayo Clinic, Rochester, MN 55905, USA
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23
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Ringe RP, Colin P, Torres JL, Yasmeen A, Lee WH, Cupo A, Ward AB, Klasse PJ, Moore JP. SOS and IP Modifications Predominantly Affect the Yield but Not Other Properties of SOSIP.664 HIV-1 Env Glycoprotein Trimers. J Virol 2019; 94:e01521-19. [PMID: 31619555 PMCID: PMC6912111 DOI: 10.1128/jvi.01521-19] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 10/08/2019] [Indexed: 01/20/2023] Open
Abstract
Soluble recombinant native-like (NL) envelope glycoprotein (Env) trimers of various human immunodeficiency virus type 1 (HIV-1) genotypes are being developed as vaccine candidates aimed at the induction of broadly neutralizing antibodies (bNAbs). The prototypic design, designated BG505 SOSIP.664, incorporates an intersubunit disulfide bond (SOS) to covalently link the gp120 and gp41 ectodomain (gp41ECTO) subunits and a point substitution, I559P (IP), to further stabilize the gp41ECTO components. Without the SOS and IP changes, proteolytically cleaved trimers tend to disintegrate into their constituent gp120 and gp41ECTO subunits. We show, however, that NL trimers lacking the SOS and/or IP change can be affinity purified in amounts sufficient for analyses of their antigenicity and thermal stability. In general, these trimer variants have properties highly comparable to those of the fully stabilized SOSIP.664 version. We conclude that the major effect of the SOS and IP changes is to substantially increase trimer stability during and after the expression process, thereby allowing useful amounts to be produced. However, once the trimers have been purified, the SOS and IP changes have only subtle impacts on thermostability and the antigenicity of bNAb and other epitopes.IMPORTANCE Recombinant trimeric proteins based on HIV-1 env genes are being developed for vaccine trials in humans. A feature of these proteins is their mimicry of the envelope glycoprotein structure on virus particles that is targeted by neutralizing antibodies, i.e., antibodies that prevent cells from becoming infected. One vaccine concept under exploration is that recombinant trimers may be able to elicit virus-neutralizing antibodies when delivered as immunogens. A commonly used design is designated SOSIP.664, a term reflecting the sequence changes that are used to stabilize the trimers and allow their production in practically useful amounts. Here, we show that these stabilizing changes act to increase trimer yield during the biosynthesis process within the producer cell but have little impact on the properties of purified trimers.
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Affiliation(s)
- Rajesh P Ringe
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York, USA
| | - Philippe Colin
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York, USA
| | - Jonathan L Torres
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, USA
- Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, The Scripps Research Institute, La Jolla, California, USA
| | - Anila Yasmeen
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York, USA
| | - Wen-Hsin Lee
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, USA
| | - Albert Cupo
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York, USA
| | - Andrew B Ward
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, USA
- Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, The Scripps Research Institute, La Jolla, California, USA
- International AIDS Vaccine Initiative (IAVI) Neutralizing Antibody Center and the Collaboration for AIDS Vaccine Discovery (CAVD), The Scripps Research Institute, La Jolla, California, USA
| | - P J Klasse
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York, USA
| | - John P Moore
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York, USA
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Torrents de la Peña A, Rantalainen K, Cottrell CA, Allen JD, van Gils MJ, Torres JL, Crispin M, Sanders RW, Ward AB. Similarities and differences between native HIV-1 envelope glycoprotein trimers and stabilized soluble trimer mimetics. PLoS Pathog 2019; 15:e1007920. [PMID: 31306470 PMCID: PMC6658011 DOI: 10.1371/journal.ppat.1007920] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Revised: 07/25/2019] [Accepted: 06/17/2019] [Indexed: 01/02/2023] Open
Abstract
The HIV-1 envelope glycoprotein (Env) trimer is located on the surface of the virus and is the target of broadly neutralizing antibodies (bNAbs). Recombinant native-like soluble Env trimer mimetics, such as SOSIP trimers, have taken a central role in HIV-1 vaccine research aimed at inducing bNAbs. We therefore performed a direct and thorough comparison of a full-length unmodified Env trimer containing the transmembrane domain and the cytoplasmic tail, with the sequence matched soluble SOSIP trimer, both based on an early Env sequence (AMC011) from an HIV+ individual that developed bNAbs. The structures of the full-length AMC011 trimer bound to either bNAb PGT145 or PGT151 were very similar to the structures of SOSIP trimers. Antigenically, the full-length and SOSIP trimers were comparable, but in contrast to the full-length trimer, the SOSIP trimer did not bind at all to non-neutralizing antibodies, most likely as a consequence of the intrinsic stabilization of the SOSIP trimer. Furthermore, the glycan composition of full-length and SOSIP trimers was similar overall, but the SOSIP trimer possessed slightly less complex and less extensively processed glycans, which may relate to the intrinsic stabilization as well as the absence of the membrane tether. These data provide insights into how to best use and improve membrane-associated full-length and soluble SOSIP HIV-1 Env trimers as immunogens. HIV-1 envelope glycoprotein (Env) trimer is the primary antigenic target for neutralizing antibodies. As such, it is the focus of subunit vaccine design efforts that aim to recapitulate the structure and native antigenic profile in a soluble, stable form capable of eliciting neutralizing antibody responses. Here, we compare the antigenicity, glycosylation and structure of a full-length, wild-type Env trimer with a corresponding soluble, SOSIP trimer that is representative of many ongoing subunit vaccine design efforts. Overall, both exhibit similar properties, and the SOSIP trimer is an accurate mimic of the wild-type Env.
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Affiliation(s)
- Alba Torrents de la Peña
- Department of Medical Microbiology, Amsterdam UMC - University of Amsterdam, Amsterdam, the Netherlands
| | - Kimmo Rantalainen
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, United States of America
| | - Christopher A. Cottrell
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, United States of America
| | - Joel D. Allen
- Centre for Biological Sciences & Institute for Life Sciences, University of Southampton, Southampton, United Kingdom
| | - Marit J. van Gils
- Department of Medical Microbiology, Amsterdam UMC - University of Amsterdam, Amsterdam, the Netherlands
| | - Jonathan L. Torres
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, United States of America
| | - Max Crispin
- Centre for Biological Sciences & Institute for Life Sciences, University of Southampton, Southampton, United Kingdom
| | - Rogier W. Sanders
- Department of Medical Microbiology, Amsterdam UMC - University of Amsterdam, Amsterdam, the Netherlands
- * E-mail: (RWS); (ABW)
| | - Andrew B. Ward
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, United States of America
- * E-mail: (RWS); (ABW)
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25
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Seabright GE, Doores KJ, Burton DR, Crispin M. Protein and Glycan Mimicry in HIV Vaccine Design. J Mol Biol 2019; 431:2223-2247. [PMID: 31028779 PMCID: PMC6556556 DOI: 10.1016/j.jmb.2019.04.016] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 04/12/2019] [Accepted: 04/13/2019] [Indexed: 01/30/2023]
Abstract
Antigenic mimicry is a fundamental tenet of structure-based vaccinology. Vaccine strategies for the human immunodeficiency virus type 1 (HIV-1) focus on the mimicry of its envelope spike (Env) due to its exposed location on the viral membrane and role in mediating infection. However, the virus has evolved to minimize the immunogenicity of conserved epitopes on the envelope spike. This principle is starkly illustrated by the presence of an extensive array of host-derived glycans, which act to shield the underlying protein from antibody recognition. Despite these hurdles, a subset of HIV-infected individuals eventually develop broadly neutralizing antibodies that recognize these virally presented glycans. Effective HIV-1 immunogens are therefore likely to involve some degree of mimicry of both the protein and glycan components of Env. As such, considerable efforts have been made to characterize the structure of the envelope spike and its glycan shield. This review summarizes the recent progress made in this field, with an emphasis on our growing understanding of the factors shaping the glycan shield of Env derived from both virus and soluble immunogens. We argue that recombinant mimics of the envelope spike are currently capable of capturing many features of the native viral glycan shield. Finally, we explore strategies through which the immunogenicity of Env glycans may be enhanced in the development of future immunogens.
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Affiliation(s)
- Gemma E Seabright
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford, Oxford, OX1 3QU, UK; School of Biological Sciences, University of Southampton, Southampton, SO17 1BJ, UK
| | - Katie J Doores
- Department of Infectious Diseases, King's College London, Guy's Hospital, London, SE1 9RT, UK
| | - Dennis R Burton
- Department of Immunology and Microbiology, the Scripps Centre for HIV/AIDS Vaccine Immunology and Immunogen Discovery (CHAVI-ID), International AIDS Vaccine Initiative Neutralizing Antibody Centre, Scripps Research, La Jolla, CA 92037, USA
| | - Max Crispin
- School of Biological Sciences, University of Southampton, Southampton, SO17 1BJ, UK; Department of Immunology and Microbiology, the Scripps Centre for HIV/AIDS Vaccine Immunology and Immunogen Discovery (CHAVI-ID), International AIDS Vaccine Initiative Neutralizing Antibody Centre, Scripps Research, La Jolla, CA 92037, USA.
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26
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Munro JB, Lee KK. Probing Structural Variation and Dynamics in the HIV-1 Env Fusion Glycoprotein. Curr HIV Res 2019; 16:5-12. [PMID: 29268688 DOI: 10.2174/1570162x16666171222110025] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Revised: 08/16/2017] [Accepted: 08/17/2017] [Indexed: 11/22/2022]
Abstract
BACKGROUND Recent advances in structural characterization of the HIV envelope glycoprotein (Env) have provided a high-resolution glimpse of the architecture of this target for neutralizing antibodies and the machinery responsible for mediating receptor binding and membrane fusion. These structures primarily capture the detailed organization of the receptor-naive, prefusion conformation of Env, but under native solution conditions Env is highly dynamic, sampling multiple conformational states as well as exhibiting local protein flexibility. METHODS Special emphasis is placed on the use of biophysical methods, including single-molecule fluorescence microscopy and hydrogen/deuterium-exchange mass spectrometry. RESULTS Using novel biophysical approaches, striking isolate-specific differences in Env's dynamic profile have been revealed that appear to underlie phenotypic differences of the viral isolates such as neutralization sensitivity and CD4 receptor reactivity. CONCLUSION Structural studies are complemented by novel biophysical investigations that enable visualization of the dynamics of HIV-1 Env under native conditions. These approaches will also enable us to gain new insights into the mechanisms of action of antibodies and drugs.
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Affiliation(s)
- James B Munro
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA, United States
| | - Kelly K Lee
- Department of Medicinal Chemistry and Biological Physics Structure and Design Program, University of Washington, Seattle, WA, United States
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27
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de Taeye SW, Go EP, Sliepen K, de la Peña AT, Badal K, Medina-Ramírez M, Lee WH, Desaire H, Wilson IA, Moore JP, Ward AB, Sanders RW. Stabilization of the V2 loop improves the presentation of V2 loop-associated broadly neutralizing antibody epitopes on HIV-1 envelope trimers. J Biol Chem 2019; 294:5616-5631. [PMID: 30728245 PMCID: PMC6462529 DOI: 10.1074/jbc.ra118.005396] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 01/15/2019] [Indexed: 11/16/2022] Open
Abstract
A successful HIV-1 vaccine will likely need to elicit broadly neutralizing antibodies (bNAbs) that target the envelope glycoprotein (Env) spike on the virus. Native-like recombinant Env trimers of the SOSIP design now serve as a platform for achieving this challenging goal. However, SOSIP trimers usually do not bind efficiently to the inferred germline precursors of bNAbs (gl-bNAbs). We hypothesized that the inherent flexibilities of the V1 and V2 variable loops in the Env trimer contribute to the poor recognition of gl-bNAb epitopes at the trimer apex that extensively involve V2 residues. To reduce local V2 flexibility and improve the binding of V2-dependent bNAbs and gl-bNAbs, we designed BG505 SOSIP.664 trimer variants containing newly created disulfide bonds intended to stabilize the V2 loop in an optimally antigenic configuration. The first variant, I184C/E190C, contained a new disulfide bond within the V2 loop, whereas the second variant, E153C/R178C, had a new disulfide bond that cross-linked V2 and V1. The resulting engineered native-like trimer variants were both more reactive with and were neutralized by V2 bNAbs and gl-bNAbs, a finding that may be valuable in the design of germline targeting and boosting trimer immunogens to create an antigenic conformation optimal for HIV vaccine development.
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Affiliation(s)
- Steven W de Taeye
- From the Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, 1105 AZ, The Netherlands
| | - Eden P Go
- the Department of Chemistry, University of Kansas, Lawrence, Kansas 66045
| | - Kwinten Sliepen
- From the Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, 1105 AZ, The Netherlands
| | - Alba Torrents de la Peña
- From the Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, 1105 AZ, The Netherlands
| | - Kimberly Badal
- From the Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, 1105 AZ, The Netherlands
| | - Max Medina-Ramírez
- From the Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, 1105 AZ, The Netherlands
| | - Wen-Hsin Lee
- the Department of Integrative Structural and Computational Biology, Scripps CHAVI-ID, IAVI Neutralizing Antibody Center and Collaboration for AIDS Vaccine Discovery, The Scripps Research Institute, La Jolla, California 92037, and
| | - Heather Desaire
- the Department of Chemistry, University of Kansas, Lawrence, Kansas 66045
| | - Ian A Wilson
- the Department of Integrative Structural and Computational Biology, Scripps CHAVI-ID, IAVI Neutralizing Antibody Center and Collaboration for AIDS Vaccine Discovery, The Scripps Research Institute, La Jolla, California 92037, and
| | - John P Moore
- the Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York 10021
| | - Andrew B Ward
- the Department of Integrative Structural and Computational Biology, Scripps CHAVI-ID, IAVI Neutralizing Antibody Center and Collaboration for AIDS Vaccine Discovery, The Scripps Research Institute, La Jolla, California 92037, and
| | - Rogier W Sanders
- From the Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, 1105 AZ, The Netherlands, .,the Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York 10021
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Li T, Zhang Z, Zhang Z, Qiao J, Rong R, Zhang Y, Yao Q, Li Z, Shen H, Huang F, Xue W, Gao S, Li S, Zheng Q, Yu H, Zhang J, Gu Y, Li S, Xia N. Characterization of native-like HIV-1 gp140 glycoprotein expressed in insect cells. Vaccine 2019; 37:1418-1427. [PMID: 30737044 DOI: 10.1016/j.vaccine.2019.01.048] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Revised: 01/15/2019] [Accepted: 01/28/2019] [Indexed: 11/25/2022]
Abstract
The trimeric HIV-1 envelope glycoprotein (Env) is critical for vaccine development aimed at achieving broadly-neutralizing antibody responses. The use of various recombinant expression systems and construct designs are associated with the resultant nature of produced proteins, especially in terms of glycosylation, antigenicity, and immunogenicity of the glycoprotein. Here, we explored an otherwise baculovirus cassette than classical one designed to express HIV-1 Env protein, including SOSIP mutation and Foldon moiety involvement. This improved design increased the ratio of the Env trimer fraction from ∼40% to ∼60% with respect to that of prototypical design, as indicated by high-performance size-exclusion chromatography and sedimentation velocity analysis. In addition, the design prolonged cell viability and enhanced the final yield (approximately 13-15 mg/L) after affinity purification. gp140 produced from insect cells mimicked the native-like trimer and mainly adopted glycosylation pattern of oligomannose glycans. The native-like Env proteins conferred cross-clade neutralizing antibody production in BALB/c mice. In summary, the expression of Env in insect cells by optimizing the baculovirus vector provides an alternative strategy for HIV-1 immunogen production and may benefit future Env-based HIV vaccine design.
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Affiliation(s)
- Tingting Li
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Zhenyong Zhang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Zhiqing Zhang
- National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Jiaming Qiao
- National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Rui Rong
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Yuyun Zhang
- National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Qiaobin Yao
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Zekai Li
- National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Honglin Shen
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Fang Huang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Wenhui Xue
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Shuangquan Gao
- National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Shaoyong Li
- National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Qingbing Zheng
- National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Hai Yu
- National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Jun Zhang
- National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Ying Gu
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Life Sciences, Xiamen University, Xiamen 361102, China; National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Public Health, Xiamen University, Xiamen 361102, China.
| | - Shaowei Li
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Life Sciences, Xiamen University, Xiamen 361102, China; National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Public Health, Xiamen University, Xiamen 361102, China.
| | - Ningshao Xia
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Life Sciences, Xiamen University, Xiamen 361102, China; National Institute of Diagnostics and Vaccine Development in Infectious Disease, School of Public Health, Xiamen University, Xiamen 361102, China
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29
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Abstract
A large array of broadly neutralizing antibodies (bnAbs) against HIV have been isolated and described, particularly in the last decade. This continually expanding array of bnAbs has crucially led to the identification of novel epitopes on the HIV envelope protein via which antibodies can block a broad range of HIV strains. Moreover, these studies have produced high-resolution understanding of these sites of vulnerability on the envelope protein. They have also clarified the mechanisms of action of bnAbs and provided detailed descriptions of B cell ontogenies from which they arise. However, it is still not possible to predict which HIV-infected individuals will go onto develop breath nor is it possible to induce neutralization breadth by immunization in humans. This review aims to discuss the major insights gained so far and also to evaluate the requirement to continue isolating and characterizing new bnAbs. While new epitopes may remain to be uncovered, a clearer probable benefit of further bnAb characterization is a greater understanding of key decision points in bnAb development within the anti-HIV immune response. This in turn may lead to new insights into how to trigger bnAbs by immunization and more clearly define the challenges to using bnAbs as therapeutic agents.
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Affiliation(s)
- Laura E McCoy
- Division of Infection and Immunity, University College London, London, UK.
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30
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Torrents de la Peña A, Sanders RW. Stabilizing HIV-1 envelope glycoprotein trimers to induce neutralizing antibodies. Retrovirology 2018; 15:63. [PMID: 30208933 PMCID: PMC6134781 DOI: 10.1186/s12977-018-0445-y] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 09/05/2018] [Indexed: 01/03/2023] Open
Abstract
An effective HIV-1 vaccine probably will need to be able to induce broadly neutralizing HIV-1 antibodies (bNAbs) in order to be efficacious. The many bNAbs that have been isolated from HIV-1 infected patients illustrate that the human immune system is able to elicit this type of antibodies. The elucidation of the structure of the HIV-1 envelope glycoprotein (Env) trimer has further fueled the search for Env immunogens that induce bNAbs, but while native Env trimer mimetics are often capable of inducing strain-specific neutralizing antibodies (NAbs) against the parental virus, they have not yet induced potent bNAb responses. To improve the performance of Env trimer immunogens, researchers have studied the immune responses that Env trimers have induced in animals; they have evaluated how to best use Env trimers in various immunization regimens; and they have engineered increasingly stabilized Env trimer variants. Here, we review the different approaches that have been used to increase the stability of HIV-1 Env trimer immunogens with the aim of improving the induction of NAbs. In particular, we draw parallels between the various approaches to stabilize Env trimers and ones that have been used by nature in extremophile microorganisms in order to survive in extreme environmental conditions.
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Affiliation(s)
- Alba Torrents de la Peña
- Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Rogier W. Sanders
- Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, NY 10021 USA
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31
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Struwe WB, Chertova E, Allen JD, Seabright GE, Watanabe Y, Harvey DJ, Medina-Ramirez M, Roser JD, Smith R, Westcott D, Keele BF, Bess JW, Sanders RW, Lifson JD, Moore JP, Crispin M. Site-Specific Glycosylation of Virion-Derived HIV-1 Env Is Mimicked by a Soluble Trimeric Immunogen. Cell Rep 2018; 24:1958-1966.e5. [PMID: 30134158 PMCID: PMC6113929 DOI: 10.1016/j.celrep.2018.07.080] [Citation(s) in RCA: 101] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 06/18/2018] [Accepted: 07/24/2018] [Indexed: 12/29/2022] Open
Abstract
Many broadly neutralizing antibodies (bnAbs) against HIV-1 recognize and/or penetrate the glycan shield on native, virion-associated envelope glycoprotein (Env) spikes. The same bnAbs also bind to recombinant, soluble trimeric immunogens based on the SOSIP design. While SOSIP trimers are close structural and antigenic mimics of virion Env, the extent to which their glycan structures resemble ones on infectious viruses is undefined. Here, we compare the overall glycosylation of gp120 and gp41 subunits from BG505 (clade A) virions produced in a lymphoid cell line with those from recombinant BG505 SOSIP trimers, including CHO-derived clinical grade material. We also performed detailed site-specific analyses of gp120. Glycans relevant to key bnAb epitopes are generally similar on the recombinant SOSIP and virion-derived Env proteins, although the latter do contain hotspots of elevated glycan processing. Knowledge of native versus recombinant Env glycosylation will guide vaccine design and manufacturing programs.
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Affiliation(s)
- Weston B Struwe
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK; Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, OX1 3TA, UK
| | - Elena Chertova
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Joel D Allen
- Biological Sciences and the Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Gemma E Seabright
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK; Biological Sciences and the Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Yasunori Watanabe
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK; Biological Sciences and the Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - David J Harvey
- Biological Sciences and the Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK; Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, Oxford OX3 7FZ, UK
| | - Max Medina-Ramirez
- Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - James D Roser
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Rodman Smith
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - David Westcott
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Brandon F Keele
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Julian W Bess
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Rogier W Sanders
- Department of Microbiology and Immunology, Weill Cornell Medical College, Cornell University, New York, NY, USA; Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Jeffrey D Lifson
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - John P Moore
- Department of Microbiology and Immunology, Weill Cornell Medical College, Cornell University, New York, NY, USA.
| | - Max Crispin
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK; Biological Sciences and the Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK.
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32
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Yang L, Sharma SK, Cottrell C, Guenaga J, Tran K, Wilson R, Behrens AJ, Crispin M, de Val N, Wyatt RT. Structure-Guided Redesign Improves NFL HIV Env Trimer Integrity and Identifies an Inter-Protomer Disulfide Permitting Post-Expression Cleavage. Front Immunol 2018; 9:1631. [PMID: 30065725 PMCID: PMC6056610 DOI: 10.3389/fimmu.2018.01631] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 07/02/2018] [Indexed: 11/13/2022] Open
Abstract
Soluble HIV-1 envelope glycoprotein (Env) trimers are under active investigation as vaccine candidates in relevant pre-clinical models. Like SOSIPs, the cleavage-independent native flexibly linked (NFL) trimers are faithful mimics of the Env spike. Here, we analyzed multiple new designs to explore alternative modifications, informing tertiary interactions, while maintaining NFL trimer homogeneity and integrity. Accordingly, we performed a proline (P) substitution screen in the gp41 heptad repeat 1 region, identifying other trimer-enhancing Ps, including L555P. This P improved trimer integrity compared to I559P in selected properties. Next, we screened 15 structure-guided potential cysteine pairs in gp140 and found that A501C-L663C ("CC2") forms an inter-protomer disulfide bond that demonstrably increased NFL trimer thermostability. We combined these two approaches with trimer-derived substitutions, coupled with glycine substitutions at helix-to-coil transitions, developed by our group. To increase the exposure of the fusion peptide (FP) N-terminus, we engineered an enterokinase (EK) cleavage site upstream of the FP for controlled post-expression cleavage. In combination, the redesigns resulted in highly stable and homogeneous NFL mimics derived from different clades. Following recombinant EK cleavage, the NFL trimers retained covalent linkage, maintaining a native-like structure while displaying enhanced stability and favorable antigenic features. These trimers also displayed increased exposure of neutralizing epitopes in the FP and gp120/gp41 interface, while retaining other neutralizing epitopes and occluding non-neutralizing elements. This array of Env-structure-guided designs reveals additional interactive regions in the prefusion state of the HIV Env spike, affording the development of novel antigens and immunogens.
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Affiliation(s)
- Lifei Yang
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, United States
| | - Shailendra Kumar Sharma
- International AIDS Vaccine Initiative, Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA, United States
| | - Christopher Cottrell
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, United States
| | - Javier Guenaga
- International AIDS Vaccine Initiative, Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA, United States
| | - Karen Tran
- International AIDS Vaccine Initiative, Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA, United States
| | - Richard Wilson
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, United States
| | - Anna-Janina Behrens
- Department of Biochemistry, Oxford Glycobiology Institute, University of Oxford, Oxford, United Kingdom
| | - Max Crispin
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, United States
- Department of Biochemistry, Oxford Glycobiology Institute, University of Oxford, Oxford, United Kingdom
- Centre for Biological Sciences, Institute of Life Sciences, Highfield Campus, University of Southampton, Southampton, United Kingdom
| | - Natalia de Val
- Center for Molecular Microscopy (CMM), Center for Cancer Research (CCR), National Cancer Institute (NCI), National Institutes of Health (NIH), Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, United States
| | - Richard T. Wyatt
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, United States
- International AIDS Vaccine Initiative, Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA, United States
- Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, The Scripps Research Institute, La Jolla, CA, United States
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Comparison of Uncleaved and Mature Human Immunodeficiency Virus Membrane Envelope Glycoprotein Trimers. J Virol 2018; 92:JVI.00277-18. [PMID: 29618643 DOI: 10.1128/jvi.00277-18] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 03/26/2018] [Indexed: 12/21/2022] Open
Abstract
The mature envelope glycoprotein (Env) spike on the surfaces of human immunodeficiency virus type 1 (HIV-1)-infected cells and virions is derived from proteolytic cleavage of a trimeric gp160 glycoprotein precursor. In these studies, we compared the conformations of cleaved and uncleaved membrane Envs with truncated cytoplasmic tails to those of stabilized soluble gp140 SOSIP.664 Env trimers. Deletion of the gp41 cytoplasmic tail did not significantly affect the sensitivity of viruses with the HIV-1AD8 Env to inhibition by antibodies or a CD4-mimetic compound. After glutaraldehyde fixation and purification from membranes, a cleaved Env exhibited a hydrodynamic radius of ∼10 nm and an antibody-binding profile largely consistent with that expected based on virus neutralization sensitivity. The purified cleaved Env trimers exhibited a hollow architecture with a central void near the trimer axis. Uncleaved Env, cross-linked and purified in parallel, exhibited a hydrodynamic radius similar to that of the cleaved Env. However, the uncleaved Env was recognized by poorly neutralizing antibodies and appeared by negative-stain electron microscopy to sample multiple conformations. Compared with membrane Envs, stabilized soluble gp140 SOSIP.664 Env trimers appear to be more compact, as reflected in their smaller hydrodynamic radii and negative-stain electron microscopy structures. The antigenic features of the soluble gp140 SOSIP.664 Env trimers differed from those of the cleaved membrane Env, particularly in gp120 V3 and some CD4-binding-site epitopes. Thus, proteolytic maturation allows the membrane-anchored Env to achieve a conformation that retains functional metastability but masks epitopes for poorly neutralizing antibodies.IMPORTANCE The entry of human immunodeficiency virus type 1 (HIV-1) into host cells is mediated by the envelope glycoprotein (Env) spike on the surface of the virus. Host antibodies elicited during natural HIV-1 infection or by vaccination can potentially recognize the Env spike and block HIV-1 infection. However, the changing shape of the HIV-1 Env spike protects the virus from antibody binding. Understanding the shapes of natural and man-made preparations of HIV-1 Envs will assist the development of effective vaccines against the virus. Here, we evaluate the effects of several Env modifications commonly used to produce Env preparations for vaccine studies and the determination of structure. We found that the cleavage of the HIV-1 Env precursor helps Env to assume its natural shape, which resists the binding of many commonly elicited antibodies. Stabilized soluble Envs exhibit more compact shapes but expose some Env elements differently than the natural Env.
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Sequential immunizations with a panel of HIV-1 Env virus-like particles coach immune system to make broadly neutralizing antibodies. Sci Rep 2018; 8:7807. [PMID: 29773829 PMCID: PMC5958130 DOI: 10.1038/s41598-018-25960-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Accepted: 03/26/2018] [Indexed: 12/24/2022] Open
Abstract
Broadly neutralizing antibodies (bnAbs) are correlated with passive HIV/SHIV protection and are desirable components of a HIV protective immunity. In the current study, we have designed a sequential-immunization strategy with a panel of envelope glycoprotein (Env)-enriched virus-like particles (VLPs) from various HIV-1 clades (A-E) to elicit bnAbs with high breadth and potency of neutralization in rabbits. We have compared this regimen with repetitive immunizations of individual Env (subtype B) VLPs or a mixture of various Env VLPs. Our results demonstrate that the sequential immunization group of animals induced significantly higher IgG endpoint titers against respective HIV Env (autologous) antigen than other control groups. Animals vaccinated sequentially showed an increase in the antibody endpoint titers and IgG antibody secreting cells (ASCs) against Con-S Env protein. Sequential immunizations with various Env VLPs promoted antibody avidity indices and enhanced bnAb responses against a panel of HIV pseudotyped virions including some of the tier 3 pseudostrains. Sequential immunizations with various VLPs displaying "native-like" HIV-1 Envs elicited bnAb responses with increased breadth and potency of neutralization.
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Structure of a cleavage-independent HIV Env recapitulates the glycoprotein architecture of the native cleaved trimer. Nat Commun 2018; 9:1956. [PMID: 29769533 PMCID: PMC5955915 DOI: 10.1038/s41467-018-04272-y] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 04/13/2018] [Indexed: 11/25/2022] Open
Abstract
Furin cleavage of the HIV envelope glycoprotein is an essential step for cell entry that enables formation of well-folded, native-like glycosylated trimers, releases constraints on the fusion peptide, and limits enzymatic processing of the N-glycan shield. Here, we show that a cleavage-independent, stabilized, soluble Env trimer mimic (BG505 NFL.664) exhibits a “closed-form”, native-like, prefusion conformation akin to furin-cleaved Env trimers. The crystal structure of BG505 NFL.664 at 3.39 Å resolution with two potent bNAbs also identifies the full epitopes of PGV19 and PGT122 that target the receptor binding site and N332 supersite, respectively. Quantitative site-specific analysis of the glycan shield reveals that native-like glycan processing is maintained despite furin-independent maturation in the secretory pathway. Thus, cleavage-independent NFL Env trimers exhibit quaternary protein and carbohydrate structures similar to the native viral spike that further validate their potential as vaccine immunogen candidates. Native-like soluble HIV envelope (Env) trimers are potential vaccine immunogens, and elimination of furin-dependence could provide a DNA-based alternative. Here, Sarkar et al. show that a cleavage-independent Env construct recapitulates the architecture and glycosylation of the native cleaved trimer.
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36
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Yu WH, Zhao P, Draghi M, Arevalo C, Karsten CB, Suscovich TJ, Gunn B, Streeck H, Brass AL, Tiemeyer M, Seaman M, Mascola JR, Wells L, Lauffenburger DA, Alter G. Exploiting glycan topography for computational design of Env glycoprotein antigenicity. PLoS Comput Biol 2018; 14:e1006093. [PMID: 29677181 PMCID: PMC5931682 DOI: 10.1371/journal.pcbi.1006093] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 05/02/2018] [Accepted: 03/16/2018] [Indexed: 11/20/2022] Open
Abstract
Mounting evidence suggests that glycans, rather than merely serving as a “shield”, contribute critically to antigenicity of the HIV envelope (Env) glycoprotein, representing critical antigenic determinants for many broadly neutralizing antibodies (bNAbs). While many studies have focused on defining the role of individual glycans or groups of proximal glycans in bNAb binding, little is known about the effects of changes in the overall glycan landscape in modulating antibody access and Env antigenicity. Here we developed a systems glycobiology approach to reverse engineer the complexity of HIV glycan heterogeneity to guide antigenicity-based de novo glycoprotein design. bNAb binding was assessed against a panel of 94 recombinant gp120 monomers exhibiting defined glycan site occupancies. Using a Bayesian machine learning algorithm, bNAb-specific glycan footprints were identified and used to design antigens that selectively alter bNAb antigenicity as a proof-of concept. Our approach provides a new design strategy to predictively modulate antigenicity via the alteration of glycan topography, thereby focusing the humoral immune response on sites of viral vulnerability for HIV. Carbohydrates on the HIV Env glycoprotein, previously often considered as a “shield” permitting immune evasion, can themselves represent targets for broadly neutralizing antibody (bNAb) recognition. Efforts to define the impact of individual glycans on bNAb recognition have clearly illustrated the critical nature of individual or groups of glycans on bNAb binding. However, glycans represent half the mass of the HIV envelope glycoprotein, representing a lattice of interacting sugars that shape the topographical landscape that alters antibody accessiblity to the underlying protein. However, whether alterations in individual glycans alter the broader interactions among glycans, proximal and distal, has not been heretofore rigorously examined, nor how this lattice may be actively exploited to improve antigenicity. To address this challenge, we describe here a systems glycobiology approach to reverse engineer the complex relationship between bNAb binding and glycan landscape effects on Env proteins spanning across various clades and tiers. Glycan occupancy was interrogated across every potential N-glycan site in 94 recombinant gp120 recombinant antigens. Sequences, glycan occupancy, as well as bNAb binding profiles were integrated across each of the 94-atngeins to generate a machine learning computational model enabling the identification of the glycan site determinants involved in binding to any given bNAb. Moreover, this model was used to generate a panel of novel gp120 variants with augmented selective bNAb binding profiles, further validating the contributions of glycans in Env antigen design. Whether glycan-optimization will additionally influence immunogenicity, particularly on emerging stabilized trimers, is unknown, but this study provides a proof of concept for selectively and agnostically exploiting both proximal and distal viral protein glycosylation in a principled manner to improve target Ab binding profiles.
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Affiliation(s)
- Wen-Han Yu
- Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology and Harvard University, Cambridge, MA, United States of America
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States of America
| | - Peng Zhao
- Complex Carbohydrate Research Center, Department of Biochemistry and Molecular Biology, The University of Georgia, Athens, Georgia, United States of America
| | - Monia Draghi
- Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology and Harvard University, Cambridge, MA, United States of America
| | - Claudia Arevalo
- Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology and Harvard University, Cambridge, MA, United States of America
| | - Christina B Karsten
- Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology and Harvard University, Cambridge, MA, United States of America
| | - Todd J Suscovich
- Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology and Harvard University, Cambridge, MA, United States of America
| | - Bronwyn Gunn
- Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology and Harvard University, Cambridge, MA, United States of America
| | - Hendrik Streeck
- Institute for HIV Research, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Abraham L Brass
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA, United States of America
| | - Michael Tiemeyer
- Complex Carbohydrate Research Center, Department of Biochemistry and Molecular Biology, The University of Georgia, Athens, Georgia, United States of America
| | - Michael Seaman
- Beth Israel Deaconess Medical Center, Boston, Massachusetts, United States of America
| | - John R Mascola
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States of America
| | - Lance Wells
- Complex Carbohydrate Research Center, Department of Biochemistry and Molecular Biology, The University of Georgia, Athens, Georgia, United States of America
| | - Douglas A Lauffenburger
- Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology and Harvard University, Cambridge, MA, United States of America
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States of America
| | - Galit Alter
- Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology and Harvard University, Cambridge, MA, United States of America
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Abstract
Vaccine design efforts against the human immunodeficiency virus (HIV) have been greatly stimulated by the observation that many infected patients eventually develop highly potent broadly neutralizing antibodies (bnAbs). Importantly, these bnAbs have evolved to recognize not only the two protein components of the viral envelope protein (Env) but also the numerous glycans that form a protective barrier on the Env protein. Because Env is heavily glycosylated compared to host glycoproteins, the glycans have become targets for the antibody response. Therefore, considerable efforts have been made in developing and validating biophysical methods to elucidate the complex structure of the Env-spike glycoprotein, with its combination of glycan and protein epitopes. We illustrate here how the application of robust biophysical methods has transformed our understanding of the structure and function of the HIV Env spike and stimulated innovation in vaccine design strategies that takes into account the essential glycan components.
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Affiliation(s)
- Max Crispin
- Centre for Biological Sciences and Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, United Kingdom;
| | - Andrew B Ward
- Department of Integrative Structural and Computational Biology, Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, International AIDS Vaccine Initiative Neutralizing Antibody Center, and Collaboration for AIDS Vaccine Discovery, The Scripps Research Institute, La Jolla, California 92037, USA; ,
| | - Ian A Wilson
- Department of Integrative Structural and Computational Biology, Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, International AIDS Vaccine Initiative Neutralizing Antibody Center, and Collaboration for AIDS Vaccine Discovery, The Scripps Research Institute, La Jolla, California 92037, USA; , .,Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California 92037, USA
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Behrens AJ, Kumar A, Medina-Ramirez M, Cupo A, Marshall K, Cruz Portillo VM, Harvey DJ, Ozorowski G, Zitzmann N, Wilson IA, Ward AB, Struwe WB, Moore JP, Sanders RW, Crispin M. Integrity of Glycosylation Processing of a Glycan-Depleted Trimeric HIV-1 Immunogen Targeting Key B-Cell Lineages. J Proteome Res 2018; 17:987-999. [PMID: 29420040 DOI: 10.1021/acs.jproteome.7b00639] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Broadly neutralizing antibodies (bNAbs) that target the trimeric HIV-1 envelope glycoprotein spike (Env) are tools that can guide the design of recombinant Env proteins intended to engage the predicted human germline precursors of bNAbs (gl-bNAbs). The protein components of gl-bNAb epitopes are often masked by glycans, while mature bNAbs can evolve to accommodate or bypass these shielding glycans. The design of germline-targeting Env immunogens therefore includes the targeted deletion of specific glycan sites. However, the processing of glycans on Env trimers can be influenced by the density with which they are packed together, a highly relevant point given the essential contributions under-processed glycans make to multiple bNAb epitopes. We sought to determine the impact of the removal of 15 potential N-glycan sites (5 per protomer) from the germline-targeting soluble trimer, BG505 SOSIP.v4.1-GT1, using quantitative, site-specific N-glycan mass spectrometry analysis. We find that, compared with SOSIP.664, there was little overall change in the glycan profile but only subtle increases in the extent of processing at sites immediately adjacent to where glycans had been deleted. We conclude that multiple glycans can be deleted from BG505 SOSIP trimers without perturbing the overall integrity of the glycan shield.
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Affiliation(s)
- Anna-Janina Behrens
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford , South Parks Road, Oxford OX1 3QU, United Kingdom
| | - Abhinav Kumar
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford , South Parks Road, Oxford OX1 3QU, United Kingdom
| | - Max Medina-Ramirez
- Laboratory of Experimental Virology, Department of Medical Microbiology, Center for Infection and Immunity Amsterdam (CINIMA), Academic Medical Center of the University of Amsterdam , 1105 AZ Amsterdam, The Netherlands
| | - Albert Cupo
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York , New York, New York 10021, United States
| | - Kevin Marshall
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York , New York, New York 10021, United States
| | - Victor M Cruz Portillo
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York , New York, New York 10021, United States
| | - David J Harvey
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford , South Parks Road, Oxford OX1 3QU, United Kingdom
| | - Gabriel Ozorowski
- Department of Integrative Structural and Computational Biology, IAVI Neutralizing Antibody Center and CAVD, Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, The Scripps Research Institute , La Jolla, California 92037, United States
| | - Nicole Zitzmann
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford , South Parks Road, Oxford OX1 3QU, United Kingdom
| | - Ian A Wilson
- Department of Integrative Structural and Computational Biology, IAVI Neutralizing Antibody Center and CAVD, Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, The Scripps Research Institute , La Jolla, California 92037, United States.,Skaggs Institute for Chemical Biology, The Scripps Research Institute , La Jolla, California 92037, United States
| | - Andrew B Ward
- Department of Integrative Structural and Computational Biology, IAVI Neutralizing Antibody Center and CAVD, Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, The Scripps Research Institute , La Jolla, California 92037, United States
| | - Weston B Struwe
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford , South Parks Road, Oxford OX1 3QU, United Kingdom
| | - John P Moore
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York , New York, New York 10021, United States
| | - Rogier W Sanders
- Laboratory of Experimental Virology, Department of Medical Microbiology, Center for Infection and Immunity Amsterdam (CINIMA), Academic Medical Center of the University of Amsterdam , 1105 AZ Amsterdam, The Netherlands.,Department of Microbiology and Immunology, Weill Cornell Medical College, New York , New York, New York 10021, United States
| | - Max Crispin
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford , South Parks Road, Oxford OX1 3QU, United Kingdom.,Centre for Biological Sciences and Institute for Life Sciences, University of Southampton , Southampton SO17 1BJ, United Kingdom
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39
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Dey AK, Cupo A, Ozorowski G, Sharma VK, Behrens AJ, Go EP, Ketas TJ, Yasmeen A, Klasse PJ, Sayeed E, Desaire H, Crispin M, Wilson IA, Sanders RW, Hassell T, Ward AB, Moore JP. cGMP production and analysis of BG505 SOSIP.664, an extensively glycosylated, trimeric HIV-1 envelope glycoprotein vaccine candidate. Biotechnol Bioeng 2017; 115:885-899. [PMID: 29150937 PMCID: PMC5852640 DOI: 10.1002/bit.26498] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 10/30/2017] [Accepted: 11/14/2017] [Indexed: 12/30/2022]
Abstract
We describe the properties of BG505 SOSIP.664 HIV‐1 envelope glycoprotein trimers produced under current Good Manufacturing Practice (cGMP) conditions. These proteins are the first of a new generation of native‐like trimers that are the basis for many structure‐guided immunogen development programs aimed at devising how to induce broadly neutralizing antibodies (bNAbs) to HIV‐1 by vaccination. The successful translation of this prototype demonstrates the feasibility of producing similar immunogens on an appropriate scale and of an acceptable quality for Phase I experimental medicine clinical trials. BG505 SOSIP.664 trimers are extensively glycosylated, contain numerous disulfide bonds and require proteolytic cleavage, all properties that pose a substantial challenge to cGMP production. Our strategy involved creating a stable CHO cell line that was adapted to serum‐free culture conditions to produce envelope glycoproteins. The trimers were then purified by chromatographic methods using a 2G12 bNAb affinity column and size‐exclusion chromatography. The chosen procedures allowed any adventitious viruses to be cleared from the final product to the required extent of >12 log10. The final cGMP production run yielded 3.52 g (peptidic mass) of fully purified trimers (Drug Substance) from a 200 L bioreactor, a notable yield for such a complex glycoprotein. The purified trimers were fully native‐like as judged by negative‐stain electron microscopy, and were stable over a multi‐month period at room temperature or below and for at least 1 week at 50°C. Their antigenicity, disulfide bond patterns, and glycan composition were consistent with trimers produced on a research laboratory scale. The methods reported here should pave the way for the cGMP production of other native‐like Env glycoprotein trimers of various designs and genotypes.
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Affiliation(s)
- Antu K Dey
- International AIDS Vaccine Initiative, New York, New York
| | - Albert Cupo
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York
| | - Gabriel Ozorowski
- Department of Integrative Structural and Computational Biology, International AIDS Vaccine Initiative (IAVI) Neutralizing Antibody Center and the Collaboration for AIDS Vaccine Discovery, The Scripps Research Institute, La Jolla, California
| | | | - Anna-Janina Behrens
- Department of Biochemistry, Oxford Glycobiology Institute, University of Oxford, Oxford, UK.,Centre for Biological Sciences and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Eden P Go
- Department of Chemistry, The University of Kansas, Lawrence, Kansas
| | - Thomas J Ketas
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York
| | - Anila Yasmeen
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York
| | - Per J Klasse
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York
| | - Eddy Sayeed
- International AIDS Vaccine Initiative, New York, New York
| | - Heather Desaire
- Department of Chemistry, The University of Kansas, Lawrence, Kansas
| | - Max Crispin
- Department of Biochemistry, Oxford Glycobiology Institute, University of Oxford, Oxford, UK
| | - Ian A Wilson
- Department of Integrative Structural and Computational Biology, International AIDS Vaccine Initiative (IAVI) Neutralizing Antibody Center and the Collaboration for AIDS Vaccine Discovery, The Scripps Research Institute, La Jolla, California
| | - Rogier W Sanders
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York.,Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Thomas Hassell
- International AIDS Vaccine Initiative, New York, New York
| | - Andrew B Ward
- Department of Integrative Structural and Computational Biology, International AIDS Vaccine Initiative (IAVI) Neutralizing Antibody Center and the Collaboration for AIDS Vaccine Discovery, The Scripps Research Institute, La Jolla, California
| | - John P Moore
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York
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40
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de Taeye SW, de la Peña AT, Vecchione A, Scutigliani E, Sliepen K, Burger JA, van der Woude P, Schorcht A, Schermer EE, van Gils MJ, LaBranche CC, Montefiori DC, Wilson IA, Moore JP, Ward AB, Sanders RW. Stabilization of the gp120 V3 loop through hydrophobic interactions reduces the immunodominant V3-directed non-neutralizing response to HIV-1 envelope trimers. J Biol Chem 2017; 293:1688-1701. [PMID: 29222332 PMCID: PMC5798299 DOI: 10.1074/jbc.ra117.000709] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 12/07/2017] [Indexed: 11/12/2022] Open
Abstract
To provide protective immunity against circulating primary HIV-1 strains, a vaccine most likely has to induce broadly neutralizing antibodies to the HIV-1 envelope glycoprotein (Env) spike. Recombinant Env trimers such as the prototype BG505 SOSIP.664 that closely mimic the native Env spike can induce autologous neutralizing antibodies (NAbs) against relatively resistant (tier 2) primary viruses. Ideally, Env immunogens should present broadly neutralizing antibody epitopes but limit the presentation of immunodominant non-NAb epitopes that might induce off-target and potentially interfering responses. The V3 loop in gp120 is such a non-NAb epitope that can effectively elicit non-NAbs when animals are immunized with SOSIP.664 trimers. V3 immunogenicity can be diminished, but not abolished, by reducing the conformational flexibility of trimers via targeted sequence changes, including an A316W substitution in V3, that create the SOSIP.v4.1 and SOSIP.v5.2 variants. Here, we further modified these trimer designs by introducing leucine residues at V3 positions 306 and 308 to create hydrophobic interactions with the tryptophan residue at position 316 and with other topologically proximal sites in the V1V2 domain. Together, these modifications further stabilized the resulting SOSIP.v5.2 S306L/R308L trimers in the prefusion state in which V3 is sequestered. When we tested these trimers as immunogens in rabbits, the induction of V3 non-NAbs was significantly reduced compared with the SOSIP.v5.2 trimers and even more so compared with the SOSIP.664 prototype, without affecting the autologous NAb response. Hence, these additional trimer sequence modifications may be beneficial for immunization strategies that seek to minimize off-target non-NAb responses.
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Affiliation(s)
- Steven W de Taeye
- From the Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, Amsterdam, 1105 AZ, The Netherlands
| | - Alba Torrents de la Peña
- From the Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, Amsterdam, 1105 AZ, The Netherlands
| | - Andrea Vecchione
- From the Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, Amsterdam, 1105 AZ, The Netherlands
| | - Enzo Scutigliani
- From the Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, Amsterdam, 1105 AZ, The Netherlands
| | - Kwinten Sliepen
- From the Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, Amsterdam, 1105 AZ, The Netherlands
| | - Judith A Burger
- From the Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, Amsterdam, 1105 AZ, The Netherlands
| | - Patricia van der Woude
- From the Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, Amsterdam, 1105 AZ, The Netherlands
| | - Anna Schorcht
- From the Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, Amsterdam, 1105 AZ, The Netherlands
| | - Edith E Schermer
- From the Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, Amsterdam, 1105 AZ, The Netherlands
| | - Marit J van Gils
- From the Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, Amsterdam, 1105 AZ, The Netherlands
| | - Celia C LaBranche
- the Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710
| | - David C Montefiori
- the Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710
| | - Ian A Wilson
- the Department of Integrative Structural and Computational Biology, Scripps CHAVI-ID, IAVI Neutralizing Antibody Center and Collaboration for AIDS Vaccine Discovery, Scripps Research Institute, La Jolla, California 92037, and
| | - John P Moore
- the Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York 10021
| | - Andrew B Ward
- the Department of Integrative Structural and Computational Biology, Scripps CHAVI-ID, IAVI Neutralizing Antibody Center and Collaboration for AIDS Vaccine Discovery, Scripps Research Institute, La Jolla, California 92037, and
| | - Rogier W Sanders
- From the Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, Amsterdam, 1105 AZ, The Netherlands, .,the Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York 10021
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41
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Soluble Prefusion Closed DS-SOSIP.664-Env Trimers of Diverse HIV-1 Strains. Cell Rep 2017; 21:2992-3002. [DOI: 10.1016/j.celrep.2017.11.016] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Revised: 08/01/2017] [Accepted: 11/03/2017] [Indexed: 11/16/2022] Open
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42
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High-Throughput Protein Engineering Improves the Antigenicity and Stability of Soluble HIV-1 Envelope Glycoprotein SOSIP Trimers. J Virol 2017; 91:JVI.00862-17. [PMID: 28878072 DOI: 10.1128/jvi.00862-17] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Accepted: 08/23/2017] [Indexed: 01/11/2023] Open
Abstract
Soluble envelope glycoprotein (Env) trimers (SOSIP.664 gp140) are attractive HIV-1 vaccine candidates, with structures that mimic the native membrane-bound Env spike (gp160). Since engineering trimers can be limited by the difficulty of rationally predicting beneficial mutations, here we used a more comprehensive mutagenesis approach with the goal of identifying trimer variants with improved antigenic and stability properties. We created 341 cysteine pairs at predicted points of stabilization throughout gp140, 149 proline residue substitutions at every residue of the gp41 ectodomain, and 362 space-filling residue substitutions at every hydrophobic and aromatic residue in gp140. The parental protein target, the clade B strain B41 SOSIP.664 gp140, does not bind the broadly neutralizing antibody PGT151 and so was used here to identify improved variants that also provide insight into the structural basis for Env antigenicity. Each of the 852 mutants was expressed in human cells and screened for antigenicity using four different monoclonal antibodies (MAbs), including PGT151. We identified 29 trimer variants with antigenic improvements derived from each of the three mutagenesis strategies. We selected four variants (Q203F, T538F, I548F, and M629P) for more comprehensive biochemical, structural, and antigenicity analyses. The T538F substitution had the most beneficial effect overall, including restoration of the PGT151 epitope. The improved B41 SOSIP.664 trimer variants identified here may be useful for vaccine and structural studies.IMPORTANCE Soluble Env trimers have become attractive HIV-1 vaccine candidates, but the prototype designs are capable of further improvement through protein engineering. Using a high-throughput screening technology (shotgun mutagenesis) to create and evaluate 852 variants, we were able to identify sequence changes that were beneficial to the antigenicity and stability of soluble trimers based on the clade B B41 env gene. The strategies described here may be useful for identifying a wider range of antigenically and structurally improved soluble trimers based on multiple genotypes for use in programs intended to create a broadly protective HIV-1 vaccine.
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Guenaga J, Garces F, de Val N, Stanfield RL, Dubrovskaya V, Higgins B, Carrette B, Ward AB, Wilson IA, Wyatt RT. Glycine Substitution at Helix-to-Coil Transitions Facilitates the Structural Determination of a Stabilized Subtype C HIV Envelope Glycoprotein. Immunity 2017; 46:792-803.e3. [PMID: 28514686 PMCID: PMC5439057 DOI: 10.1016/j.immuni.2017.04.014] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 03/16/2017] [Accepted: 04/25/2017] [Indexed: 11/17/2022]
Abstract
Advances in HIV-1 envelope glycoprotein (Env) design generate native-like trimers and high-resolution clade A, B, and G structures and elicit neutralizing antibodies. However, a high-resolution clade C structure is critical, as this subtype accounts for the majority of HIV infections worldwide, but well-ordered clade C Env trimers are more challenging to produce due to their instability. Based on targeted glycine substitutions in the Env fusion machinery, we defined a general approach that disfavors helical transitions leading to post-fusion conformations, thereby favoring the pre-fusion state. We generated a stabilized, soluble clade C Env (16055 NFL) and determined its crystal structure at 3.9 Å. Its overall conformation is similar to SOSIP.664 and native Env trimers but includes a covalent linker between gp120 and gp41, an engineered 201-433 disulfide bond, and density corresponding to 22 N-glycans. Env-structure-guided design strategies resulted in multiple homogeneous cross-clade immunogens with the potential to advance HIV vaccine development.
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Affiliation(s)
- Javier Guenaga
- IAVI Neutralizing Antibody Center at The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Fernando Garces
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Natalia de Val
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Robyn L Stanfield
- IAVI Neutralizing Antibody Center at The Scripps Research Institute, La Jolla, CA 92037, USA; Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Viktoriya Dubrovskaya
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Brett Higgins
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Barbara Carrette
- IAVI Neutralizing Antibody Center at The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Andrew B Ward
- IAVI Neutralizing Antibody Center at The Scripps Research Institute, La Jolla, CA 92037, USA; Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA; Scripps Center for HIV/AIDS Vaccine Immunology & Immunogen Discovery (CHAVI-ID), La Jolla, CA 92037, USA
| | - Ian A Wilson
- IAVI Neutralizing Antibody Center at The Scripps Research Institute, La Jolla, CA 92037, USA; Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA; Scripps Center for HIV/AIDS Vaccine Immunology & Immunogen Discovery (CHAVI-ID), La Jolla, CA 92037, USA; The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
| | - Richard T Wyatt
- IAVI Neutralizing Antibody Center at The Scripps Research Institute, La Jolla, CA 92037, USA; Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA; Scripps Center for HIV/AIDS Vaccine Immunology & Immunogen Discovery (CHAVI-ID), La Jolla, CA 92037, USA.
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Abstract
PURPOSE OF REVIEW A vaccine that elicits antibody responses that can neutralize the diversity of HIV clades has not yet been achieved, and is a major focus of HIV vaccine research. Here, we provide an update on the barriers to eliciting such antibodies, and how advances in immunogen design may circumvent these roadblocks, focusing on data published in the last year. RECENT FINDINGS Studies of how broadly neutralizing antibodies (bNAbs) develop in HIV-infected donors continue to produce key insights, suggesting that for some viral targets there are common pathways to developing breadth. Germline-targeting strategies, that aim to recruit rare precursors of bNAbs, have shown promise in immunogenicity studies, and structural biology has led to advances in immunogen design. Mapping of strain-specific tier 2 vaccine responses has highlighted the challenges that remain in driving antibodies toward breadth. SUMMARY Elucidation of the HIV envelope structure, together with an understanding of how bNAbs emerge in vivo has guided the design of new immunogens and vaccine strategies that show promise for eliciting protective antibodies.
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Abstract
Structure determination of the HIV-1 envelope glycoprotein (Env) presented a number of challenges, but several high-resolution structures have now become available. In 2013, cryo-EM and x-ray structures of soluble, cleaved SOSIP Env trimers from the clade A BG505 strain provided the first glimpses into the Env trimer fold as well as more the variable regions. A recent cryo-EM structure of a native full-length trimer without any stabilizing mutations had the same core structure, but revealed new insights and features. A more comprehensive and higher resolution understanding of the glycan shield has also emerged, enabling a more complete representation of the Env glycoprotein structure. Complexes of Env trimers with broadly neutralizing antibodies have surprisingly illustrated that most of the Env surface can be targeted in natural infection and that the neutralizing epitopes are almost all composed of both peptide and glycan components. These structures have also provided further evidence of the inherent plasticity of Env and how antibodies can exploit this flexibility by perturbing or even stabilizing the trimer to facilitate neutralization. These breakthroughs have stimulated further design and stabilization of Env trimers as well as other platforms to generate trimers that now span multiple subtypes. These Env trimers when used as immunogens, have led to the first vaccine-induced neutralizing antibodies for structural and functional analyses.
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Affiliation(s)
- Andrew B Ward
- Department of Integrative Structural and Computational Biology, International AIDS Vaccine Initiative Neutralizing Antibody Center, Collaboration for AIDS Vaccine Discovery, and Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, La Jolla, CA, USA
| | - Ian A Wilson
- Department of Integrative Structural and Computational Biology, International AIDS Vaccine Initiative Neutralizing Antibody Center, Collaboration for AIDS Vaccine Discovery, and Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, La Jolla, CA, USA.,Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA, USA
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46
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Kumar R, Ozorowski G, Kumar V, Holden LG, Shrivastava T, Patil S, Deshpande S, Ward AB, Bhattacharya J. Characterization of a stable HIV-1 B/C recombinant, soluble, and trimeric envelope glycoprotein (Env) highly resistant to CD4-induced conformational changes. J Biol Chem 2017; 292:15849-15858. [PMID: 28743743 PMCID: PMC5612115 DOI: 10.1074/jbc.m117.803056] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 07/22/2017] [Indexed: 11/06/2022] Open
Abstract
The HIV-1 envelope (Env) is a glycoprotein consisting of a trimer of heterodimers containing gp120 and gp41 subunits that mediates virus entry and is a major target of broadly neutralizing antibodies (bnAbs) developed during infection in some individuals. The engagement of the HIV-1 gp120 glycoprotein to the host CD4 protein triggers conformational changes in gp120 that allow its binding to co-receptors and is necessary for virus entry to establish infection. Native-like HIV-1 Env immunogens representing distinct clades have been proposed to improve immunogenicity. In the present study, we examined the basis of resistance of an HIV-1 B/C recombinant Env (LT5.J4b12C) to non-neutralizing antibodies targeting CD4-induced Env epitopes in the presence of soluble CD4 (sCD4). Using native polyacrylamide gel shift assay and negative-stain EM, we found that the prefusion conformational state of LT5.J4b12C trimeric Env was largely unaffected in the presence of excess sCD4 with most Env trimers appearing to be in a ligand-free state. This resistance to CD4-induced conformational changes was associated with a lower affinity for CD4. Moreover, the LT5.J4b12C trimeric Env preferentially bound to the neutralizing antibodies compared with non-neutralizing antibodies. Taken together, we report on an HIV-1 B/C recombinant, native-like trimeric Env protein that is highly resistant to CD4-induced conformational changes but displays epitopes recognized by a diverse array of bnAbs. Such features make this B/C recombinant trimeric Env a useful addition to the pool of other recently identified native-like HIV-1 Env trimers suitable for use as antigenic bait for bnAb isolation, structural studies, and use as potential immunogens.
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Affiliation(s)
- Rajesh Kumar
- From the HIV Vaccine Translational Research Laboratory, Translational Health Science and Technology Institute, National Capital Region Biotech Science Cluster, Faridabad, Haryana 121001, India
| | - Gabriel Ozorowski
- Department of Integrative Structural and Computational Biology, Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, International AIDS Vaccine Initiative Neutralizing Antibody Center and Collaboration for AIDS Vaccine Discovery, The Scripps Research Institute, La Jolla, California 92037, and
| | - Vivek Kumar
- From the HIV Vaccine Translational Research Laboratory, Translational Health Science and Technology Institute, National Capital Region Biotech Science Cluster, Faridabad, Haryana 121001, India
| | - Lauren G Holden
- Department of Integrative Structural and Computational Biology, Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, International AIDS Vaccine Initiative Neutralizing Antibody Center and Collaboration for AIDS Vaccine Discovery, The Scripps Research Institute, La Jolla, California 92037, and
| | - Tripti Shrivastava
- From the HIV Vaccine Translational Research Laboratory, Translational Health Science and Technology Institute, National Capital Region Biotech Science Cluster, Faridabad, Haryana 121001, India
| | - Shilpa Patil
- From the HIV Vaccine Translational Research Laboratory, Translational Health Science and Technology Institute, National Capital Region Biotech Science Cluster, Faridabad, Haryana 121001, India
| | - Suprit Deshpande
- From the HIV Vaccine Translational Research Laboratory, Translational Health Science and Technology Institute, National Capital Region Biotech Science Cluster, Faridabad, Haryana 121001, India
| | - Andrew B Ward
- Department of Integrative Structural and Computational Biology, Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, International AIDS Vaccine Initiative Neutralizing Antibody Center and Collaboration for AIDS Vaccine Discovery, The Scripps Research Institute, La Jolla, California 92037, and
| | - Jayanta Bhattacharya
- From the HIV Vaccine Translational Research Laboratory, Translational Health Science and Technology Institute, National Capital Region Biotech Science Cluster, Faridabad, Haryana 121001, India, .,International AIDS Vaccine Initiative, New York, New York 10004
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Abstract
Purpose of review To provide an update on the latest developments in the field of HIV-1 antibody-based soluble envelope glycoprotein (Env) trimer design for vaccine use. Recent findings The development of soluble native-like HIV-1 Env trimer immunogens has moved the field of antibody-based vaccine design forward dramatically over the past few years with refinement of various stabilizing approaches. However, despite this progress, significant challenges remain. Firstly, although trimers are relatively stable in solution, they nevertheless sample different conformational states, some of which may be less relevant to binding and induction of broadly neutralizing antibodies (bNAbs). Secondly, these trimers expose unwanted immunodominant surfaces that may distract the adaptive immune response from recognizing more immunorecessive but conserved neutralization-relevant surfaces on the trimer. The availability of atomic-resolution structural information has allowed guided design of mutations that have further stabilized trimers and allowed reduced exposure of unwanted epitopes. Moreover, chemical cross-linking approaches that do not require structural information have also contributed to trimer stabilization and selection of particular conformational forms. However, current knowledge suggests that strategies additional to trimer stabilization will be required to elicit bNAb, including targeting naïve B cell receptors with specific immunogens, and guiding B cell lineages toward recognizing conserved surfaces on Env with high affinity. Summary This review will give a perspective on these challenges, and summarize current approaches to overcoming them with the aim of developing immunogens to elicit bNAb responses in humans by active vaccination.
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Reducing V3 Antigenicity and Immunogenicity on Soluble, Native-Like HIV-1 Env SOSIP Trimers. J Virol 2017; 91:JVI.00677-17. [PMID: 28539451 PMCID: PMC5512241 DOI: 10.1128/jvi.00677-17] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 05/15/2017] [Indexed: 01/01/2023] Open
Abstract
Native-like trimers of the SOSIP design are being developed as immunogens in human immunodeficiency virus type 1 (HIV-1) vaccine development programs. These trimers display the epitopes for multiple broadly neutralizing antibodies (bNAbs) but can also expose binding sites for some types of nonneutralizing antibodies (non-NAbs). Among the latter are epitopes in the gp120 V3 region that are highly immunogenic when SOSIP trimers are evaluated in animal models. It is presently uncertain whether antibodies against V3 can interfere with the induction of NAbs, but there are good arguments in favor of suppressing such “off-target” immune responses. Accordingly, we have assessed how to minimize the exposure of V3 non-NAb epitopes and thereby reduce their immunogenicity by introducing N-glycans within the V3 region of BG505 SOSIP trimers. We found that inserting glycans at positions 306 and 314 (termed M1 and M7) markedly reduced V3 antigenicity while improving the presentation of trimer apex bNAb epitopes. Both added glycans were shown to be predominantly of the Man6GlcNAc2 form. The additional introduction of the E64K ground-state stabilizing substitution markedly reduced or ablated soluble CD4 (sCD4) induction of non-NAb epitopes in V3 and/or associated with the coreceptor binding site. When a V3 glycan- and E64K-modified trimer variant, BG505 SOSIP.664-E64K.M1M7, was tested in rabbits, V3 immunogenicity was eliminated while the autologous NAb response was unchanged. IMPORTANCE Trimeric proteins are being developed for future HIV-1 vaccine trials in humans, with the goal of eliciting broadly active neutralizing antibodies (NAbs) that are active against a wide variety of circulating strains. In animal models, the present generation of native-like trimer immunogens, exemplified by the BG505 SOSIP.664 construct, induces narrow-specificity antibodies against the neutralization-resistant (tier-2), sequence-matched virus and more broadly active antibodies against sequence-divergent atypically neutralization-sensitive (tier-1) viruses. A concern in the trimer immunogen design field has been whether the latter off-target antibodies might interfere with the induction of the more desired responses to tier-2 epitopes. Here, we have inserted two glycans into the dominant site for tier-1 NAbs, the gp120 V3 region, to block the induction of off-target antibodies. We characterized the new trimers, tested them as immunogens in rabbits, and found that the blocking glycans eliminated the induction of tier-1 NAbs to V3-epitopes.
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Improving the Expression and Purification of Soluble, Recombinant Native-Like HIV-1 Envelope Glycoprotein Trimers by Targeted Sequence Changes. J Virol 2017; 91:JVI.00264-17. [PMID: 28381572 DOI: 10.1128/jvi.00264-17] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 03/30/2017] [Indexed: 11/20/2022] Open
Abstract
Soluble, recombinant native-like envelope glycoprotein (Env) trimers of various human immunodeficiency virus type 1 (HIV-1) genotypes are being developed for structural studies and as vaccine candidates aimed at the induction of broadly neutralizing antibodies (bNAbs). The prototypic design is designated SOSIP.664, but many HIV-1 env genes do not yield fully native-like trimers efficiently. One such env gene is CZA97.012 from a neutralization-resistant (tier 2) clade C virus. As appropriately purified, native-like CZA97.012 SOSIP.664 trimers induce autologous neutralizing antibodies (NAbs) efficiently in immunized rabbits, we sought to improve the efficiency with which they can be produced and to better understand the limitations to the original design. By using structure- and antigenicity-guided mutagenesis strategies focused on the V2 and V3 regions and the gp120-gp41 interface, we developed the CZA97 SOSIP.v4.2-M6.IT construct. Fully native-like, stable trimers that display multiple bNAb epitopes could be expressed from this construct in a stable CHO cell line and purified at an acceptable yield using either a PGT145 or a 2G12 bNAb affinity column. We also show that similar mutagenesis strategies can be used to improve the yields and properties of SOSIP.664 trimers of the DU422, 426c, and 92UG037 genotypes.IMPORTANCE Recombinant trimeric proteins based on HIV-1 env genes are being developed for future vaccine trials in humans. A feature of these proteins is their mimicry of the envelope glycoprotein (Env) structure on virus particles that is targeted by neutralizing antibodies, i.e., antibodies that prevent cells from becoming infected. The vaccine concept under exploration is that recombinant trimers may be able to elicit virus-neutralizing antibodies when delivered as immunogens. Because HIV-1 is extremely variable, a practical vaccine may need to incorporate Env trimers derived from multiple different virus sequences. Accordingly, we need to understand how to make recombinant trimers from many different env genes. Here, we show how to produce trimers from a clade C virus, CZA97.012, by using an array of protein engineering techniques to improve a prototypic construct. We also show that the methods may have wider utility for other env genes, thereby further guiding immunogen design.
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Glycosylation Benchmark Profile for HIV-1 Envelope Glycoprotein Production Based on Eleven Env Trimers. J Virol 2017; 91:JVI.02428-16. [PMID: 28202756 DOI: 10.1128/jvi.02428-16] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 02/02/2017] [Indexed: 02/02/2023] Open
Abstract
HIV-1 envelope glycoprotein (Env) glycosylation is important because individual glycans are components of multiple broadly neutralizing antibody epitopes, while shielding other sites that might otherwise be immunogenic. The glycosylation on Env is influenced by a variety of factors, including the genotype of the protein, the cell line used for its expression, and the details of the construct design. Here, we used a mass spectrometry (MS)-based approach to map the complete glycosylation profile at every site in multiple HIV-1 Env trimers, accomplishing two goals. (i) We determined which glycosylation sites contain conserved glycan profiles across many trimeric Envs. (ii) We identified the variables that impact Env's glycosylation profile at sites with divergent glycosylation. Over half of the gp120 glycosylation sites on 11 different trimeric Envs have a conserved glycan profile, indicating that a native consensus glycosylation profile does indeed exist among trimers. We showed that some soluble gp120s and gp140s exhibit highly divergent glycosylation profiles compared to trimeric Env. We also assessed the impact of several variables on Env glycosylation: truncating the full-length Env; producing Env, instead of the more virologically relevant T lymphocytes, in CHO cells; and purifying Env with different chromatographic platforms, including nickel-nitrilotriacetic acid (Ni-NTA), 2G12, and PGT151 affinity. This report provides the first consensus glycosylation profile of Env trimers, which should serve as a useful benchmark for HIV-1 vaccine developers. This report also defines the sites where glycosylation may be impacted when Env trimers are truncated or produced in CHO cells.IMPORTANCE A protective HIV-1 vaccine will likely include a recombinant version of the viral envelope glycoprotein (Env). Env is highly glycosylated, and yet vaccine developers have lacked guidance on how to assess whether their immunogens have optimal glycosylation. The following important questions are still unanswered. (i) What is the "target" glycosylation profile, when the goal is to generate a natively glycosylated protein? (ii) What variables exert the greatest influence on Env glycosylation? We identified numerous sites on Env where the glycosylation profile does not deviate in 11 different Env trimers, and we investigated the impact on the divergent glycosylation profiles of changing the genotype of the Env sequence, the construct design, the purification method, and the producer cell type. The data presented here give vaccine developers a "glycosylation target" for their immunogens, and they show how protein production variables can impact Env glycosylation.
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