1
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Li D, Liu L, Ye X, Chen Y, Ren Q, Xu S, Ren Y, Cao H, Wang T. Intermediate open state of CD4-bound HIV-1 env heterotrimers in asia CRFs. Biochem Biophys Res Commun 2024; 725:150249. [PMID: 38880081 DOI: 10.1016/j.bbrc.2024.150249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2024] [Accepted: 06/09/2024] [Indexed: 06/18/2024]
Abstract
The HIV-1 envelope glycoprotein (Env) plays crucial role in viral infection by facilitating viral attachment to host cells and inducing fusion of the virus with the host cell membrane. This fusion allows the HIV-1 viral genome to enter the target cell then triggering various stages of the viral life cycle. The native Env directly interacts with the main receptor CD4 and the co-receptor (CCR5 or CXCR4) in human cell membrane then induces membrane fusion. The elucidation of the structure of Env with CD4 and co-receptors in different HIV-1 subtypes is essential for the understanding of the mechanism of virus entry. Here we report the Cryo-EM structure of the CD4-bound HIV-1 heterotrimeric Env from Asia prevalent CRF07_BC CH119 strain. In this structure, the binding of three CD4 molecules with Env induced extensively conformational changes in gp120, resulting in the transformation of the Env from close state to intermediate open state. Additionally, the conformational shift of V1/V2 loops of the heterotrimeric Env allosterically expose the V3 loop and promoting the further interactions with co-receptor CCR5 or CXCR4. These findings not only illustrate the structural complexity and plasticity of HIV-1 Env but also give new insights how the biological trimeric Env initialize the immune recognition and membrane fusion.
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Affiliation(s)
- Dan Li
- School of basic medical Sciences, Capital Medical University, 10 Xitoutiao You'anMen Street, Beijing, 100069, China; Institute of Infectious Diseases, Shenzhen Bay Laboratory, Guangming District, Shenzhen, 518132, China
| | - Li Liu
- Institute of Infectious Diseases, Shenzhen Bay Laboratory, Guangming District, Shenzhen, 518132, China; Joint Laboratory for Infectious Disease Prevention and Control, Hygienic Section of Longhua Center for Disease Control and Prevention, Longhua District, Shenzhen, 518109, China
| | - Xuejun Ye
- Institute of Infectious Diseases, Shenzhen Bay Laboratory, Guangming District, Shenzhen, 518132, China
| | - Yuyang Chen
- Institute of Infectious Diseases, Shenzhen Bay Laboratory, Guangming District, Shenzhen, 518132, China
| | - Qiaoju Ren
- Institute of Infectious Diseases, Shenzhen Bay Laboratory, Guangming District, Shenzhen, 518132, China
| | - ShaoJian Xu
- Joint Laboratory for Infectious Disease Prevention and Control, Hygienic Section of Longhua Center for Disease Control and Prevention, Longhua District, Shenzhen, 518109, China
| | - Yan Ren
- Joint Laboratory for Infectious Disease Prevention and Control, Hygienic Section of Longhua Center for Disease Control and Prevention, Longhua District, Shenzhen, 518109, China
| | - He Cao
- Joint Laboratory for Infectious Disease Prevention and Control, Hygienic Section of Longhua Center for Disease Control and Prevention, Longhua District, Shenzhen, 518109, China.
| | - Tao Wang
- Institute of Infectious Diseases, Shenzhen Bay Laboratory, Guangming District, Shenzhen, 518132, China; Joint Laboratory for Infectious Disease Prevention and Control, Hygienic Section of Longhua Center for Disease Control and Prevention, Longhua District, Shenzhen, 518109, China; Key Laboratory of Computational Chemistry and Drug Design, Peking University Shenzhen Graduate School, Nanshan District, Shenzhen, 518055, China.
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2
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Wang S, Chan KW, Wei D, Ma X, Liu S, Hu G, Park S, Pan R, Gu Y, Nazzari AF, Olia AS, Xu K, Lin BC, Louder MK, McKee K, Doria-Rose NA, Montefiori D, Seaman MS, Zhou T, Kwong PD, Arthos J, Kong XP, Lu S. Human CD4-binding site antibody elicited by polyvalent DNA prime-protein boost vaccine neutralizes cross-clade tier-2-HIV strains. Nat Commun 2024; 15:4301. [PMID: 38773089 PMCID: PMC11109196 DOI: 10.1038/s41467-024-48514-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Accepted: 05/03/2024] [Indexed: 05/23/2024] Open
Abstract
The vaccine elicitation of HIV tier-2-neutralization antibodies has been a challenge. Here, we report the isolation and characterization of a CD4-binding site (CD4bs) specific monoclonal antibody, HmAb64, from a human volunteer immunized with a polyvalent DNA prime-protein boost HIV vaccine. HmAb64 is derived from heavy chain variable germline gene IGHV1-18 and light chain germline gene IGKV1-39. It has a third heavy chain complementarity-determining region (CDR H3) of 15 amino acids. On a cross-clade panel of 208 HIV-1 pseudo-virus strains, HmAb64 neutralized 20 (10%), including tier-2 strains from clades B, BC, C, and G. The cryo-EM structure of the antigen-binding fragment of HmAb64 in complex with a CNE40 SOSIP trimer revealed details of its recognition; HmAb64 uses both heavy and light CDR3s to recognize the CD4-binding loop, a critical component of the CD4bs. This study demonstrates that a gp120-based vaccine can elicit antibodies capable of tier 2-HIV neutralization.
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Affiliation(s)
- Shixia Wang
- Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA, 01655, USA
| | - Kun-Wei Chan
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY, 10016, USA
| | - Danlan Wei
- Laboratory of Immune Regulation, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, 20892, USA
| | - Xiuwen Ma
- Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA, 01655, USA
| | - Shuying Liu
- SYL Consulting, Thousand Oak, CA, 91320, USA
| | - Guangnan Hu
- Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA, 01655, USA
| | - Saeyoung Park
- Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA, 01655, USA
| | - Ruimin Pan
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY, 10016, USA
| | - Ying Gu
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, 20892, USA
| | - Alexandra F Nazzari
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, 20892, USA
| | - Adam S Olia
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, 20892, USA
| | - Kai Xu
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, 20892, USA
| | - Bob C Lin
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, 20892, USA
| | - Mark K Louder
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, 20892, USA
| | - Krisha McKee
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, 20892, USA
| | - Nicole A Doria-Rose
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, 20892, USA
| | | | - Michael S Seaman
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, 02115, USA
| | - Tongqing Zhou
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, 20892, USA
| | - Peter D Kwong
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, 20892, USA
| | - James Arthos
- Laboratory of Immune Regulation, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, 20892, USA
| | - Xiang-Peng Kong
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY, 10016, USA
| | - Shan Lu
- Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA, 01655, USA.
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3
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Bonner X, Sondgeroth A, McCue A, Nicely N, Tripathy A, Spielvogel E, Moeser M, Ke R, Leiderman K, Joseph SB, Swanstrom R. Stoichiometry for entry and binding properties of the Env protein of R5 T cell-tropic HIV-1 and its evolutionary variant of macrophage-tropic HIV-1. mBio 2024; 15:e0032124. [PMID: 38426750 PMCID: PMC11210212 DOI: 10.1128/mbio.00321-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Accepted: 02/06/2024] [Indexed: 03/02/2024] Open
Abstract
Human immunodeficiency virus type 1 typically requires a high density of CD4 for efficient entry as a mechanism to target CD4+ T cells (T-tropic), with CCR5 being used most often as the coreceptor. When target T cells are limiting, the virus can evolve to infect cells with a low density of CD4 such as macrophages (M-tropic). The entry phenotype is known to be encoded in the viral Env protein on the surface of the virus particle. Using data showing a dose response for infectivity based on CD4 surface density, we built a model consistent with T-tropic viruses requiring multiple CD4 molecules to mediate infection, whereas M-tropic viruses can infect cells using a single CD4 receptor molecule interaction. We also found that T-tropic viruses bound to the surface of cells with a low density of CD4 are released more slowly than M-tropic viruses which we modeled to be due to multiple interactions of the T-tropic virus with multiple CD4 molecules to allow the initial stable binding. Finally, we found that some M-tropic Env proteins, as the gp120 subunit, possess an enhanced affinity for CD4 compared with their T-tropic pair, indicating that the evolution of macrophage tropism can be reflected both in the closed Env trimer conformation on the virion surface and, in some cases, also in the open confirmation of gp120 Env. Collectively, these studies reveal differences in the stoichiometry of interaction of T-tropic and M-tropic viruses with CD4 and start to identify the basis of binding differences at the biochemical level. IMPORTANCE Human immunodeficiency virus type 1 normally targets CD4+ T cells for viral replication. When T cells are limiting, the virus can evolve to infect myeloid cells. The evolutionary step involves a change from requiring a high surface density of CD4 for entry to being able to infect cells with a low density of CD4, as is found on myeloid lineage cells such as macrophage and microglia. Viruses able to infect macrophages efficiently are most often found in the CNS late in the disease course, and such viruses may contribute to neurocognitive impairment. Here, we examine the CD4 binding properties of the viral Env protein to explore these two different entry phenotypes.
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Affiliation(s)
- Xavier Bonner
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Amy Sondgeroth
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Amelia McCue
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Nathan Nicely
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Ashutosh Tripathy
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Ean Spielvogel
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Matthew Moeser
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Ruian Ke
- T-6, Theoretical Biology and Biophysics, Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico, USA
| | - Karin Leiderman
- Department of Mathematics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Computational Medicine Program, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Sarah B. Joseph
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Ronald Swanstrom
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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4
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Tam EH, Peng Y, Cheah MXY, Yan C, Xiao T. Neutralizing antibodies to block viral entry and for identification of entry inhibitors. Antiviral Res 2024; 224:105834. [PMID: 38369246 DOI: 10.1016/j.antiviral.2024.105834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 02/01/2024] [Accepted: 02/07/2024] [Indexed: 02/20/2024]
Abstract
Neutralizing antibodies (NAbs) are naturally produced by our immune system to combat viral infections. Clinically, neutralizing antibodies with potent efficacy and high specificity have been extensively used to prevent and treat a wide variety of viral infections, including Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), Human Immunodeficiency Virus (HIV), Dengue Virus (DENV) and Hepatitis B Virus (HBV). An overwhelmingly large subset of clinically effective NAbs operates by targeting viral envelope proteins to inhibit viral entry into the host cell. Binding of viral envelope protein to the host receptor is a critical rate limiting step triggering a cascade of downstream events, including endocytosis, membrane fusion and pore formation to allow viral entry. In recent years, improved structural knowledge on these processes have allowed researchers to also leverage NAbs as an indispensable tool in guiding discovery of novel antiviral entry inhibitors, providing drug candidates with high efficacy and pan-genus specificity. This review will summarize the latest progresses on the applications of NAbs as effective entry inhibitors and as important tools to develop antiviral therapeutics by high-throughput drug screenings, rational design of peptidic entry inhibitor mimicking NAbs and in silico computational modeling approaches.
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Affiliation(s)
- Ee Hong Tam
- School of Biological Sciences, Nanyang Technological University 637551, Singapore; Institute of Structural Biology, Nanyang Technological University 636921, Singapore
| | - Yu Peng
- School of Biological Sciences, Nanyang Technological University 637551, Singapore; Institute of Structural Biology, Nanyang Technological University 636921, Singapore
| | - Megan Xin Yan Cheah
- Institute of Molecular and Cell Biology, A*STAR (Agency of Science, Technology and Research) 138673, Singapore
| | - Chuan Yan
- Institute of Molecular and Cell Biology, A*STAR (Agency of Science, Technology and Research) 138673, Singapore
| | - Tianshu Xiao
- School of Biological Sciences, Nanyang Technological University 637551, Singapore; Institute of Structural Biology, Nanyang Technological University 636921, Singapore.
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5
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Biswas S, Kuwata T, Yamauchi S, Okazaki K, Kaku Y, Hasan MZ, Morioka H, Matsushita S. Idiotopes of antibodies against HIV-1 CD4-induced epitope shared with those against microorganisms. Immunology 2024; 171:534-548. [PMID: 38102962 DOI: 10.1111/imm.13742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Accepted: 12/04/2023] [Indexed: 12/17/2023] Open
Abstract
Induction of antibodies (Abs) against the conformational CD4-induced (CD4i) epitope is frequent in HIV-1 infection. However, the mechanism of development of anti-CD4i Abs is unclear. We used anti-idiotypic (aID) monoclonal Abs (mAbs) of anti-CD4i mAbs to isolate anti-CD4i mAbs from infected subjects and track the causative antigens. One anti-aID mAb sorted from infected subjects by aID mAbs had the characteristics of anti-CD4i Abs, including IGHV1-69 usage and ability to bind to HIV-1 Env enhanced by sCD4. Critical amino acid sequences for the binding of six anti-aID mAbs, with shared idiotope to anti-CD4i mAbs, were analysed by phage display. The identified amino acid sequences showed similarity to proteins from human microbiota and infectious agents. Peptides synthesized from Caudoviricetes sp and Vibrio vulnificus based on the identified sequences were reactive to most anti-aID and some anti-CD4i mAbs. These results suggest that anti-CD4i Abs may evolve from B cells primed by microorganisms.
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Affiliation(s)
- Shashwata Biswas
- Division of Clinical Retrovirology, Joint Research Center for Human Retrovirus Infection, Kumamoto University, Kumamoto, Japan
| | - Takeo Kuwata
- Division of Clinical Retrovirology, Joint Research Center for Human Retrovirus Infection, Kumamoto University, Kumamoto, Japan
| | - Soichiro Yamauchi
- Department of Analytical and Biophysical Chemistry, Faculty of Medical and Pharmaceutical Sciences, Kumamoto University, Kumamoto, Japan
| | - Kyo Okazaki
- Department of Analytical and Biophysical Chemistry, Faculty of Medical and Pharmaceutical Sciences, Kumamoto University, Kumamoto, Japan
| | - Yu Kaku
- Division of Clinical Retrovirology, Joint Research Center for Human Retrovirus Infection, Kumamoto University, Kumamoto, Japan
| | - Md Zahid Hasan
- Division of Clinical Retrovirology, Joint Research Center for Human Retrovirus Infection, Kumamoto University, Kumamoto, Japan
| | - Hiroshi Morioka
- Department of Analytical and Biophysical Chemistry, Faculty of Medical and Pharmaceutical Sciences, Kumamoto University, Kumamoto, Japan
| | - Shuzo Matsushita
- Division of Clinical Retrovirology, Joint Research Center for Human Retrovirus Infection, Kumamoto University, Kumamoto, Japan
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6
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Ao Y, Grover JR, Gifford L, Han Y, Zhong G, Katte R, Li W, Bhattacharjee R, Zhang B, Sauve S, Qin W, Ghimire D, Haque MA, Arthos J, Moradi M, Mothes W, Lemke EA, Kwong PD, Melikyan GB, Lu M. Bioorthogonal click labeling of an amber-free HIV-1 provirus for in-virus single molecule imaging. Cell Chem Biol 2024; 31:487-501.e7. [PMID: 38232732 PMCID: PMC10960674 DOI: 10.1016/j.chembiol.2023.12.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 10/13/2023] [Accepted: 12/21/2023] [Indexed: 01/19/2024]
Abstract
Structural dynamics of human immunodeficiency virus 1 (HIV-1) envelope (Env) glycoprotein mediate cell entry and facilitate immune evasion. Single-molecule FRET using peptides for Env labeling revealed structural dynamics of Env, but peptide use risks potential effects on structural integrity/dynamics. While incorporating noncanonical amino acids (ncAAs) into Env by amber stop-codon suppression, followed by click chemistry, offers a minimally invasive approach, this has proved to be technically challenging for HIV-1. Here, we develope an intact amber-free HIV-1 system that overcomes hurdles of preexisting viral amber codons. We achieved dual-ncAA incorporation into Env on amber-free virions, enabling single-molecule Förster resonance energy transfer (smFRET) studies of click-labeled Env that validated the previous peptide-based labeling approaches by confirming the intrinsic propensity of Env to dynamically sample multiple conformational states. Amber-free click-labeled Env also enabled real-time tracking of single virion internalization and trafficking in cells. Our system thus permits in-virus bioorthogonal labeling of proteins, compatible with studies of virus entry, trafficking, and egress from cells.
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Affiliation(s)
- Yuanyun Ao
- Department of Cellular and Molecular Biology, School of Medicine, University of Texas at Tyler Health Science Center, Tyler, TX 75708, USA
| | - Jonathan R Grover
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Levi Gifford
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Yang Han
- Department of Cellular and Molecular Biology, School of Medicine, University of Texas at Tyler Health Science Center, Tyler, TX 75708, USA
| | - Guohua Zhong
- Department of Cellular and Molecular Biology, School of Medicine, University of Texas at Tyler Health Science Center, Tyler, TX 75708, USA
| | - Revansiddha Katte
- Department of Cellular and Molecular Biology, School of Medicine, University of Texas at Tyler Health Science Center, Tyler, TX 75708, USA
| | - Wenwei Li
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Rajanya Bhattacharjee
- Biocentre, Departments of Biology and Chemistry, Johannes Gutenberg-University Mainz, Hanns-Dieter-Hüsch-Weg 17, 55128 Mainz, Germany; International PhD Program of the Institute of Molecular Biology, Hanns-Dieter-Hüsch-Weg 17, 55128 Mainz, Germany
| | - Baoshan Zhang
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Stephanie Sauve
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR 72701, USA
| | - Wenyi Qin
- Department of Cellular and Molecular Biology, School of Medicine, University of Texas at Tyler Health Science Center, Tyler, TX 75708, USA
| | - Dibya Ghimire
- Department of Cellular and Molecular Biology, School of Medicine, University of Texas at Tyler Health Science Center, Tyler, TX 75708, USA
| | - Md Anzarul Haque
- Department of Cellular and Molecular Biology, School of Medicine, University of Texas at Tyler Health Science Center, Tyler, TX 75708, USA
| | - James Arthos
- Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Mahmoud Moradi
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR 72701, USA
| | - Walther Mothes
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Edward A Lemke
- Biocentre, Departments of Biology and Chemistry, Johannes Gutenberg-University Mainz, Hanns-Dieter-Hüsch-Weg 17, 55128 Mainz, Germany; Institute of Molecular Biology, Ackermannweg 4, 55128 Mainz, Germany
| | - Peter D Kwong
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Gregory B Melikyan
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Maolin Lu
- Department of Cellular and Molecular Biology, School of Medicine, University of Texas at Tyler Health Science Center, Tyler, TX 75708, USA.
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7
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Bennett AL, Edwards R, Kosheleva I, Saunders C, Bililign Y, Williams A, Bubphamala P, Manosouri K, Anasti K, Saunders KO, Alam SM, Haynes BF, Acharya P, Henderson R. Microsecond dynamics control the HIV-1 Envelope conformation. SCIENCE ADVANCES 2024; 10:eadj0396. [PMID: 38306419 PMCID: PMC10836732 DOI: 10.1126/sciadv.adj0396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Accepted: 01/03/2024] [Indexed: 02/04/2024]
Abstract
The HIV-1 Envelope (Env) glycoprotein facilitates host cell fusion through a complex series of receptor-induced structural changes. Although remarkable progress has been made in understanding the structures of various Env conformations, microsecond timescale dynamics have not been studied experimentally. Here, we used time-resolved, temperature-jump small-angle x-ray scattering to monitor structural rearrangements in an HIV-1 Env SOSIP ectodomain construct with microsecond precision. In two distinct Env variants, we detected a transition that correlated with known Env structure rearrangements with a time constant in the hundreds of microseconds range. A previously unknown structural transition was also observed, which occurred with a time constant below 10 μs, and involved an order-to-disorder transition in the trimer apex. Using this information, we engineered an Env SOSIP construct that locks the trimer in the prefusion closed state by connecting adjacent protomers via disulfides. Our findings show that the microsecond timescale structural dynamics play an essential role in controlling the Env conformation with impacts on vaccine design.
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Affiliation(s)
- Ashley L. Bennett
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
| | - Robert Edwards
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
| | - Irina Kosheleva
- BioCARS, Center for Advanced Radiation Sources, The University of Chicago, 9700 South Cass Ave, Bld 434B, Lemont, IL 60439, USA
| | - Carrie Saunders
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
| | - Yishak Bililign
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
| | - Ashliegh Williams
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
| | - Pimthada Bubphamala
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
| | - Katayoun Manosouri
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
| | - Kara Anasti
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
| | - Kevin O. Saunders
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
- Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA
- Department of Integrative Immunobiology, Duke University Medical Center, Durham, NC 27710, USA
| | - S. Munir Alam
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
- Department of Pathology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Barton F. Haynes
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
- Department of Integrative Immunobiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Priyamvada Acharya
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
- BioCARS, Center for Advanced Radiation Sources, The University of Chicago, 9700 South Cass Ave, Bld 434B, Lemont, IL 60439, USA
- Department of Biochemistry, Duke University, Durham, NC 27710, USA
| | - Rory Henderson
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
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8
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Li W, Qin Z, Nand E, Grunst MW, Grover JR, Bess JW, Lifson JD, Zwick MB, Tagare HD, Uchil PD, Mothes W. HIV-1 Env trimers asymmetrically engage CD4 receptors in membranes. Nature 2023; 623:1026-1033. [PMID: 37993716 PMCID: PMC10686830 DOI: 10.1038/s41586-023-06762-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2022] [Accepted: 10/19/2023] [Indexed: 11/24/2023]
Abstract
Human immunodeficiency virus 1 (HIV-1) infection is initiated by binding of the viral envelope glycoprotein (Env) to the cell-surface receptor CD41-4. Although high-resolution structures of Env in a complex with the soluble domains of CD4 have been determined, the binding process is less understood in native membranes5-13. Here we used cryo-electron tomography to monitor Env-CD4 interactions at the membrane-membrane interfaces formed between HIV-1 and CD4-presenting virus-like particles. Env-CD4 complexes organized into clusters and rings, bringing the opposing membranes closer together. Env-CD4 clustering was dependent on capsid maturation. Subtomogram averaging and classification revealed that Env bound to one, two and finally three CD4 molecules, after which Env adopted an open state. Our data indicate that asymmetric HIV-1 Env trimers bound to one and two CD4 molecules are detectable intermediates during virus binding to host cell membranes, which probably has consequences for antibody-mediated immune responses and vaccine immunogen design.
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Affiliation(s)
- Wenwei Li
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT, USA.
| | - Zhuan Qin
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT, USA
| | - Elizabeth Nand
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT, USA
| | - Michael W Grunst
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT, USA
| | - Jonathan R Grover
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT, USA
| | - Julian W Bess
- AIDS and Cancer Virus Program, Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Jeffrey D Lifson
- AIDS and Cancer Virus Program, Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Michael B Zwick
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Hemant D Tagare
- Department of Radiology and Biomedical Imaging, Yale University, New Haven, CT, USA
| | - Pradeep D Uchil
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT, USA
| | - Walther Mothes
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT, USA.
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9
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Dam KMA, Fan C, Yang Z, Bjorkman PJ. Intermediate conformations of CD4-bound HIV-1 Env heterotrimers. Nature 2023; 623:1017-1025. [PMID: 37993719 PMCID: PMC10686819 DOI: 10.1038/s41586-023-06639-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Accepted: 09/13/2023] [Indexed: 11/24/2023]
Abstract
HIV-1 envelope (Env) exhibits distinct conformational changes in response to host receptor (CD4) engagement. Env, a trimer of gp120 and gp41 heterodimers, has been structurally characterized in a closed, prefusion conformation with closely associated gp120s and coreceptor binding sites on gp120 V3 hidden by V1V2 loops1-4 and in fully saturated CD4-bound open Env conformations with changes including outwardly rotated gp120s and displaced V1V2 loops3-9. To investigate changes resulting from substoichiometric CD4 binding, we solved single-particle cryo-electron microscopy (cryo-EM) structures of soluble, native-like heterotrimeric Envs bound to one or two CD4 molecules. Most of the Env trimers bound to one CD4 adopted the closed, prefusion Env state, with a minority exhibiting a heterogeneous partially open Env conformation. When bound to two CD4s, the CD4-bound gp120s exhibited an open Env conformation including a four-stranded gp120 bridging sheet and displaced gp120 V1V2 loops that expose the coreceptor sites on V3. The third gp120 adopted an intermediate, occluded-open state10 that showed gp120 outward rotation but maintained the prefusion three-stranded gp120 bridging sheet with only partial V1V2 displacement and V3 exposure. We conclude that most of the engagements with one CD4 molecule were insufficient to stimulate CD4-induced conformational changes, whereas binding two CD4 molecules led to Env opening in CD4-bound protomers only. The substoichiometric CD4-bound soluble Env heterotrimer structures resembled counterparts derived from a cryo-electron tomography study of complexes between virion-bound Envs and membrane-anchored CD4 (ref. 11), validating their physiological relevance. Together, these results illuminate intermediate conformations of HIV-1 Env and illustrate its structural plasticity.
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Affiliation(s)
- Kim-Marie A Dam
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Chengcheng Fan
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Zhi Yang
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Pamela J Bjorkman
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA.
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10
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Prévost J, Chen Y, Zhou F, Tolbert WD, Gasser R, Medjahed H, Nayrac M, Nguyen DN, Gottumukkala S, Hessell AJ, Rao VB, Pozharski E, Huang RK, Matthies D, Finzi A, Pazgier M. Structure-function analyses reveal key molecular determinants of HIV-1 CRF01_AE resistance to the entry inhibitor temsavir. Nat Commun 2023; 14:6710. [PMID: 37872202 PMCID: PMC10593844 DOI: 10.1038/s41467-023-42500-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 10/12/2023] [Indexed: 10/25/2023] Open
Abstract
The HIV-1 entry inhibitor temsavir prevents the viral receptor CD4 (cluster of differentiation 4) from interacting with the envelope glycoprotein (Env) and blocks its conformational changes. To do this, temsavir relies on the presence of a residue with small side chain at position 375 in Env and is unable to neutralize viral strains like CRF01_AE carrying His375. Here we investigate the mechanism of temsavir resistance and show that residue 375 is not the sole determinant of resistance. At least six additional residues within the gp120 inner domain layers, including five distant from the drug-binding pocket, contribute to resistance. A detailed structure-function analysis using engineered viruses and soluble trimer variants reveals that the molecular basis of resistance is mediated by crosstalk between His375 and the inner domain layers. Furthermore, our data confirm that temsavir can adjust its binding mode to accommodate changes in Env conformation, a property that likely contributes to its broad antiviral activity.
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Affiliation(s)
- Jérémie Prévost
- Centre de Recherche du CHUM, Montreal, QC, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC, Canada
| | - Yaozong Chen
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - Fei Zhou
- Unit on Structural Biology, Division of Basic and Translational Biophysics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - William D Tolbert
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - Romain Gasser
- Centre de Recherche du CHUM, Montreal, QC, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC, Canada
| | | | - Manon Nayrac
- Centre de Recherche du CHUM, Montreal, QC, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC, Canada
| | - Dung N Nguyen
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - Suneetha Gottumukkala
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - Ann J Hessell
- Division of Pathobiology and Immunology, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, USA
| | - Venigalla B Rao
- Department of Biology, the Catholic University of America, Washington, DC, USA
| | - Edwin Pozharski
- Institute for Bioscience and Biotechnology Research, Rockville, MD, 20850, USA
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Rick K Huang
- Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, USA
| | - Doreen Matthies
- Unit on Structural Biology, Division of Basic and Translational Biophysics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Andrés Finzi
- Centre de Recherche du CHUM, Montreal, QC, Canada.
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC, Canada.
| | - Marzena Pazgier
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, USA.
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11
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Wang S, Chan KW, Wei D, Ma X, Liu S, Hu G, Park S, Pan R, Gu Y, Nazzari AF, Olia AS, Xu K, Lin BC, Louder MK, Doria-Rose NA, Montefiori D, Seaman MS, Zhou T, Kwong PD, Arthos J, Kong XP, Lu S. Human CD4-Binding Site Antibody Elicited by Polyvalent DNA Prime-Protein Boost Vaccine Neutralizes Cross-Clade Tier-2-HIV Strains. RESEARCH SQUARE 2023:rs.3.rs-3360161. [PMID: 37886518 PMCID: PMC10602183 DOI: 10.21203/rs.3.rs-3360161/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2023]
Abstract
The vaccine elicitation of HIV-neutralizing antibodies with tier-2-neutralization breadth has been a challenge. Here, we report the isolation and characteristics of a CD4-binding site specific monoclonal antibody, HmAb64, from a human volunteer immunized with a polyvalent gp120 DNA prime-protein boost vaccine. HmAb64 derived from heavy chain variable germline gene IGHV1-18, light chain germline gene IGKV1-39, and had a 3rd heavy chain complementarity determining region (CDR H3) of 15 amino acids. On a cross-clade panel of 208 HIV-1 pseudo-virus strains, HmAb64 neutralized 21 (10%), including tier-2 neutralization resistant strains from clades B, BC, C, and G. The cryo-EM structure of the antigen-binding fragment of HmAb64 bound to a conformation between prefusion closed and occluded open forms of envelope trimer, using both heavy and light CDR3s to recognize the CD4-binding loop, a critical component of the CD4-binding site. A gp120 subunit-based vaccine can thus elicit an antibody capable of tier 2-HIV neutralization.
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Affiliation(s)
- Shixia Wang
- Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA 01655, USA
| | - Kun-Wei Chan
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Danlan Wei
- Laboratory of Immune Regulation, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, USA
| | - Xiuwen Ma
- Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA 01655, USA
| | | | - Guangnan Hu
- Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA 01655, USA
| | - Saeyoung Park
- Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA 01655, USA
| | - Ruimin Pan
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Ying Gu
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, USA
| | - Alexandra F Nazzari
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, USA
| | - Adam S Olia
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, USA
| | - Kai Xu
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, USA
| | - Bob C Lin
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, USA
| | - Mark K Louder
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, USA
| | - Nicole A Doria-Rose
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, USA
| | | | - Michael S Seaman
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Tongqing Zhou
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, USA
| | - Peter D Kwong
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, USA
| | - James Arthos
- Laboratory of Immune Regulation, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, USA
| | - Xiang-Peng Kong
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Shan Lu
- Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA 01655, USA
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12
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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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13
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Bennett AL, Edwards RJ, Kosheleva I, Saunders C, Bililign Y, Williams A, Manosouri K, Saunders KO, Haynes BF, Acharya P, Henderson R. Microsecond dynamics control the HIV-1 envelope conformation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.17.541130. [PMID: 37292605 PMCID: PMC10245784 DOI: 10.1101/2023.05.17.541130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The HIV-1 Envelope (Env) glycoprotein facilitates host cell fusion through a complex series of receptor-induced structural changes. Although significant progress has been made in understanding the structures of various Env conformations and transition intermediates that occur within the millisecond timescale, faster transitions in the microsecond timescale have not yet been observed. In this study, we employed time-resolved, temperature-jump small angle X-ray scattering to monitor structural rearrangements in an HIV-1 Env ectodomain construct with microsecond precision. We detected a transition correlated with Env opening that occurs in the hundreds of microseconds range and another more rapid transition that preceded this opening. Model fitting indicated that the early rapid transition involved an order-to-disorder transition in the trimer apex loop contacts, suggesting that conventional conformation-locking design strategies that target the allosteric machinery may be ineffective in preventing this movement. Utilizing this information, we engineered an envelope that locks the apex loop contacts to the adjacent protomer. This modification resulted in significant angle-of-approach shifts in the interaction of a neutralizing antibody. Our findings imply that blocking the intermediate state could be crucial for inducing antibodies with the appropriate bound state orientation through vaccination.
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Affiliation(s)
- Ashley L Bennett
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
| | - R J Edwards
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
| | - Irina Kosheleva
- BioCARS, Center for Advanced Radiation Sources, The University of Chicago, 9700 South Cass Ave, Bld 434B, Lemont, IL 60439, USA
| | - Carrie Saunders
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
| | - Yishak Bililign
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
| | - Ashliegh Williams
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
| | - Katayoun Manosouri
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
| | - Kevin O Saunders
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
- Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA
| | - Barton F Haynes
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
- Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA
- Department of Biochemistry, Duke University, Durham, NC 27710, USA
| | - Priyamvada Acharya
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
- Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA
- Department of Biochemistry, Duke University, Durham, NC 27710, USA
| | - Rory Henderson
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
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14
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Grunst MW, Ladd RA, Clark NM, Gil HM, Klenchin VA, Mason R, Franchini G, Roederer M, Evans DT. Antibody-dependent cellular cytotoxicity, infected cell binding and neutralization by antibodies to the SIV envelope glycoprotein. PLoS Pathog 2023; 19:e1011407. [PMID: 37253062 PMCID: PMC10256149 DOI: 10.1371/journal.ppat.1011407] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 06/09/2023] [Accepted: 05/08/2023] [Indexed: 06/01/2023] Open
Abstract
Antibodies specific for diverse epitopes of the simian immunodeficiency virus envelope glycoprotein (SIV Env) have been isolated from rhesus macaques to provide physiologically relevant reagents for investigating antibody-mediated protection in this species as a nonhuman primate model for HIV/AIDS. With increasing interest in the contribution of Fc-mediated effector functions to protective immunity, we selected thirty antibodies representing different classes of SIV Env epitopes for a comparison of antibody-dependent cellular cytotoxicity (ADCC), binding to Env on the surface of infected cells and neutralization of viral infectivity. These activities were measured against cells infected with neutralization-sensitive (SIVmac316 and SIVsmE660-FL14) and neutralization-resistant (SIVmac239 and SIVsmE543-3) viruses representing genetically distinct isolates. Antibodies to the CD4-binding site and CD4-inducible epitopes were identified with especially potent ADCC against all four viruses. ADCC correlated well with antibody binding to virus-infected cells. ADCC also correlated with neutralization. However, several instances of ADCC without detectable neutralization or neutralization without detectable ADCC were observed. The incomplete correspondence between ADCC and neutralization shows that some antibody-Env interactions can uncouple these antiviral activities. Nevertheless, the overall correlation between neutralization and ADCC implies that most antibodies that are capable of binding to Env on the surface of virions to block infectivity are also capable of binding to Env on the surface of virus-infected cells to direct their elimination by ADCC.
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Affiliation(s)
- Michael W. Grunst
- Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Ruby A. Ladd
- Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Natasha M. Clark
- Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Hwi Min Gil
- Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Vadim A. Klenchin
- Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Rosemarie Mason
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, Maryland, United States of America
| | - Genoveffa Franchini
- Animal Models and Retroviral Vaccines Section, National Cancer Institute, Bethesda, Maryland, United States of America
| | - Mario Roederer
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, Maryland, United States of America
| | - David T. Evans
- Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
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15
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Stamos JD, Rahman MA, Gorini G, Silva de Castro I, Becerra-Flores M, Van Wazer DJ, N’Guessan KF, Clark NM, Bissa M, Gutowska A, Mason RD, Kim J, Rao M, Roederer M, Paquin-Proulx D, Evans DT, Cicala C, Arthos J, Kwong PD, Zhou T, Cardozo T, Franchini G. Effect of Passive Administration of Monoclonal Antibodies Recognizing Simian Immunodeficiency Virus (SIV) V2 in CH59-Like Coil/Helical or β-Sheet Conformations on Time of SIV mac251 Acquisition. J Virol 2023; 97:e0186422. [PMID: 36976017 PMCID: PMC10134845 DOI: 10.1128/jvi.01864-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 02/28/2023] [Indexed: 03/29/2023] Open
Abstract
The monoclonal antibodies (MAbs) NCI05 and NCI09, isolated from a vaccinated macaque that was protected from multiple simian immunodeficiency virus (SIV) challenges, both target an overlapping, conformationally dynamic epitope in SIV envelope variable region 2 (V2). Here, we show that NCI05 recognizes a CH59-like coil/helical epitope, whereas NCI09 recognizes a β-hairpin linear epitope. In vitro, NCI05 and, to a lesser extent, NCI09 mediate the killing of SIV-infected cells in a CD4-dependent manner. Compared to NCI05, NCI09 mediates higher titers of antibody-dependent cellular cytotoxicity (ADCC) to gp120-coated cells, as well as higher levels of trogocytosis, a monocyte function that contributes to immune evasion. We also found that passive administration of NCI05 or NCI09 to macaques did not affect the risk of SIVmac251 acquisition compared to controls, demonstrating that these anti-V2 antibodies alone are not protective. However, NCI05 but not NCI09 mucosal levels strongly correlated with delayed SIVmac251 acquisition, and functional and structural data suggest that NCI05 targets a transient state of the viral spike apex that is partially opened, compared to its prefusion-closed conformation. IMPORTANCE Studies suggest that the protection against SIV/simian-human immunodeficiency virus (SHIV) acquisition afforded by the SIV/HIV V1 deletion-containing envelope immunogens, delivered by the DNA/ALVAC vaccine platform, requires multiple innate and adaptive host responses. Anti-inflammatory macrophages and tolerogenic dendritic cells (DC-10), together with CD14+ efferocytes, are consistently found to correlate with a vaccine-induced decrease in the risk of SIV/SHIV acquisition. Similarly, V2-specific antibody responses mediating ADCC, Th1 and Th2 cells expressing no or low levels of CCR5, and envelope-specific NKp44+ cells producing interleukin 17 (IL-17) also are reproducible correlates of decreased risk of virus acquisition. We focused on the function and the antiviral potential of two monoclonal antibodies (NCI05 and NCI09) isolated from vaccinated animals that differ in antiviral function in vitro and recognize V2 in a linear (NCI09) or coil/helical (NCI05) conformation. We demonstrate that NCI05, but not NCI09, delays SIVmac251 acquisition, highlighting the complexity of antibody responses to V2.
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Affiliation(s)
- James D. Stamos
- Animal Models and Retroviral Vaccines Section, Vaccine Branch, National Cancer Institute, Bethesda, Maryland, USA
| | - Mohammad Arif Rahman
- Animal Models and Retroviral Vaccines Section, Vaccine Branch, National Cancer Institute, Bethesda, Maryland, USA
| | - Giacomo Gorini
- Animal Models and Retroviral Vaccines Section, Vaccine Branch, National Cancer Institute, Bethesda, Maryland, USA
| | - Isabela Silva de Castro
- Animal Models and Retroviral Vaccines Section, Vaccine Branch, National Cancer Institute, Bethesda, Maryland, USA
| | - Manuel Becerra-Flores
- New York University Grossman School of Medicine, NYU Langone Health, New York, New York, USA
| | - David J. Van Wazer
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Kombo F. N’Guessan
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, Maryland, USA
- Innate Immunology Laboratory, U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Natasha M. Clark
- Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Department of Pathology and Laboratory Medicine, University of Wisconsin—Madison, Madison, Wisconsin, USA
| | - Massimiliano Bissa
- Animal Models and Retroviral Vaccines Section, Vaccine Branch, National Cancer Institute, Bethesda, Maryland, USA
| | - Anna Gutowska
- Animal Models and Retroviral Vaccines Section, Vaccine Branch, National Cancer Institute, Bethesda, Maryland, USA
| | - Rosemarie D. Mason
- ImmunoTechnology Section, Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Jiae Kim
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, Maryland, USA
- Laboratory of Adjuvant and Antigen Research, U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Mangala Rao
- Laboratory of Adjuvant and Antigen Research, U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Mario Roederer
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
- ImmunoTechnology Section, Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Dominic Paquin-Proulx
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, Maryland, USA
- Innate Immunology Laboratory, U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - David T. Evans
- Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Department of Pathology and Laboratory Medicine, University of Wisconsin—Madison, Madison, Wisconsin, USA
| | - Claudia Cicala
- Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - James Arthos
- Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Peter D. Kwong
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Tongqing Zhou
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Timothy Cardozo
- New York University Grossman School of Medicine, NYU Langone Health, New York, New York, USA
| | - Genoveffa Franchini
- Animal Models and Retroviral Vaccines Section, Vaccine Branch, National Cancer Institute, Bethesda, Maryland, USA
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16
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Prévost J, Chen Y, Zhou F, Tolbert WD, Gasser R, Medjahed H, Gottumukkala S, Hessell AJ, Rao VB, Pozharski E, Huang RK, Matthies D, Finzi A, Pazgier M. Structure-function Analyses Reveal Key Molecular Determinants of HIV-1 CRF01_AE Resistance to the Entry Inhibitor Temsavir. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.17.537181. [PMID: 37131729 PMCID: PMC10153197 DOI: 10.1101/2023.04.17.537181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The HIV-1 entry inhibitor temsavir prevents CD4 from interacting with the envelope glycoprotein (Env) and blocks its conformational changes. To do this temsavir relies on the presence of a residue with small side chain at position 375 in Env and is unable to neutralize viral strains like CRF01_AE carrying His375. Here we investigate the mechanism of temsavir-resistance and show that residue 375 is not the sole determinant of resistance. At least six additional residues within the gp120 inner domain layers, including five distant from the drug-binding pocket, contribute to resistance. A detailed structure-function analysis using engineered viruses and soluble trimer variants reveal that the molecular basis of resistance is mediated by crosstalk between His375 and the inner domain layers. Furthermore, our data confirm that temsavir can adjust its binding mode to accommodate changes in Env conformation, a property that likely contributes to its broad-antiviral activity.
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Fernández I, Dynesen LT, Coquin Y, Pederzoli R, Brun D, Haouz A, Gessain A, Rey FA, Buseyne F, Backovic M. The crystal structure of a simian Foamy Virus receptor binding domain provides clues about entry into host cells. Nat Commun 2023; 14:1262. [PMID: 36878926 PMCID: PMC9988990 DOI: 10.1038/s41467-023-36923-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 02/21/2023] [Indexed: 03/08/2023] Open
Abstract
The surface envelope glycoprotein (Env) of all retroviruses mediates virus binding to cells and fusion of the viral and cellular membranes. A structure-function relationship for the HIV Env that belongs to the Orthoretrovirus subfamily has been well established. Structural information is however largely missing for the Env of Foamy viruses (FVs), the second retroviral subfamily. In this work we present the X-ray structure of the receptor binding domain (RBD) of a simian FV Env at 2.57 Å resolution, revealing two subdomains and an unprecedented fold. We have generated a model for the organization of the RBDs within the trimeric Env, which indicates that the upper subdomains form a cage-like structure at the apex of the Env, and identified residues K342, R343, R359 and R369 in the lower subdomain as key players for the interaction of the RBD and viral particles with heparan sulfate.
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Affiliation(s)
- Ignacio Fernández
- Institut Pasteur, Université Paris Cité, CNRS UMR3569, Unité de Virologie Structurale, 75015, Paris, France
| | - Lasse Toftdal Dynesen
- Institut Pasteur, Université Paris Cité, CNRS UMR3569, Unité d'Épidémiologie et Physiopathologie des Virus Oncogènes, 75015, Paris, France
| | - Youna Coquin
- Institut Pasteur, Université Paris Cité, CNRS UMR3569, Unité d'Épidémiologie et Physiopathologie des Virus Oncogènes, 75015, Paris, France
| | - Riccardo Pederzoli
- Institut Pasteur, Université Paris Cité, CNRS UMR3569, Unité de Virologie Structurale, 75015, Paris, France
| | - Delphine Brun
- Institut Pasteur, Université Paris Cité, CNRS UMR3569, Unité de Virologie Structurale, 75015, Paris, France
| | - Ahmed Haouz
- Institut Pasteur, Université Paris Cité, Plateforme de cristallographie-C2RT, CNRS UMR 3528, 75015, Paris, France
| | - Antoine Gessain
- Institut Pasteur, Université Paris Cité, CNRS UMR3569, Unité d'Épidémiologie et Physiopathologie des Virus Oncogènes, 75015, Paris, France
| | - Félix A Rey
- Institut Pasteur, Université Paris Cité, CNRS UMR3569, Unité de Virologie Structurale, 75015, Paris, France
| | - Florence Buseyne
- Institut Pasteur, Université Paris Cité, CNRS UMR3569, Unité d'Épidémiologie et Physiopathologie des Virus Oncogènes, 75015, Paris, France
| | - Marija Backovic
- Institut Pasteur, Université Paris Cité, CNRS UMR3569, Unité de Virologie Structurale, 75015, Paris, France.
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Ao Y, Grover JR, Han Y, Zhong G, Qin W, Ghimire D, Haque A, Bhattacharjee R, Zhang B, Arthos J, Lemke EA, Kwong PD, Lu M. An intact amber-free HIV-1 system for in-virus protein bioorthogonal click labeling that delineates envelope conformational dynamics. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.28.530526. [PMID: 36909529 PMCID: PMC10002649 DOI: 10.1101/2023.02.28.530526] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
Abstract
The HIV-1 envelope (Env) glycoprotein is conformationally dynamic and mediates membrane fusion required for cell entry. Single-molecule fluorescence resonance energy transfer (smFRET) of Env using peptide tags has provided mechanistic insights into the dynamics of Env conformations. Nevertheless, using peptide tags risks potential effects on structural integrity. Here, we aim to establish minimally invasive smFRET systems of Env on the virus by combining genetic code expansion and bioorthogonal click chemistry. Amber stop-codon suppression allows site-specifically incorporating noncanonical/unnatural amino acids (ncAAs) at introduced amber sites into proteins. However, ncAA incorporation into Env (or other HIV-1 proteins) in the virus context has been challenging due to low copies of Env on virions and incomplete amber suppression in mammalian cells. Here, we developed an intact amber-free virus system that overcomes impediments from preexisting ambers in HIV-1. Using this system, we successfully incorporated dual ncAAs at amber-introduced sites into Env on intact virions. Dual-ncAA incorporated Env retained similar neutralization sensitivities to neutralizing antibodies as wildtype. smFRET of click-labeled Env on intact amber-free virions recapitulated conformational profiles of Env. The amber-free HIV-1 infectious system also permits in-virus protein bioorthogonal labeling, compatible with various advanced microscopic studies of virus entry, trafficking, and egress in living cells. Amber-free HIV-1 infectious systems actualized minimal invasive Env tagging for smFRET, versatile for in-virus bioorthogonal click labeling in advanced microscopic studies of virus-host interactions.
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Bibollet-Ruche F, Russell RM, Ding W, Liu W, Li Y, Wagh K, Wrapp D, Habib R, Skelly AN, Roark RS, Sherrill-Mix S, Wang S, Rando J, Lindemuth E, Cruickshank K, Park Y, Baum R, Carey JW, Connell AJ, Li H, Giorgi EE, Song GS, Ding S, Finzi A, Newman A, Hernandez GE, Machiele E, Cain DW, Mansouri K, Lewis MG, Montefiori DC, Wiehe KJ, Alam SM, Teng IT, Kwong PD, Andrabi R, Verkoczy L, Burton DR, Korber BT, Saunders KO, Haynes BF, Edwards RJ, Shaw GM, Hahn BH. A Germline-Targeting Chimpanzee SIV Envelope Glycoprotein Elicits a New Class of V2-Apex Directed Cross-Neutralizing Antibodies. mBio 2023; 14:e0337022. [PMID: 36629414 PMCID: PMC9973348 DOI: 10.1128/mbio.03370-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 12/12/2022] [Indexed: 01/12/2023] Open
Abstract
HIV-1 and its SIV precursors share a broadly neutralizing antibody (bNAb) epitope in variable loop 2 (V2) at the envelope glycoprotein (Env) trimer apex. Here, we tested the immunogenicity of germ line-targeting versions of a chimpanzee SIV (SIVcpz) Env in human V2-apex bNAb heavy-chain precursor-expressing knock-in mice and as chimeric simian-chimpanzee immunodeficiency viruses (SCIVs) in rhesus macaques (RMs). Trimer immunization of knock-in mice induced V2-directed NAbs, indicating activation of V2-apex bNAb precursor-expressing mouse B cells. SCIV infection of RMs elicited high-titer viremia, potent autologous tier 2 neutralizing antibodies, and rapid sequence escape in the canonical V2-apex epitope. Six of seven animals also developed low-titer heterologous plasma breadth that mapped to the V2-apex. Antibody cloning from two of these animals identified multiple expanded lineages with long heavy chain third complementarity determining regions that cross-neutralized as many as 7 of 19 primary HIV-1 strains, but with low potency. Negative stain electron microscopy (NSEM) of members of the two most cross-reactive lineages confirmed V2 targeting but identified an angle of approach distinct from prototypical V2-apex bNAbs, with antibody binding either requiring or inducing an occluded-open trimer. Probing with conformation-sensitive, nonneutralizing antibodies revealed that SCIV-expressed, but not wild-type SIVcpz Envs, as well as a subset of primary HIV-1 Envs, preferentially adopted a more open trimeric state. These results reveal the existence of a cryptic V2 epitope that is exposed in occluded-open SIVcpz and HIV-1 Env trimers and elicits cross-neutralizing responses of limited breadth and potency. IMPORTANCE An effective HIV-1 vaccination strategy will need to stimulate rare precursor B cells of multiple bNAb lineages and affinity mature them along desired pathways. Here, we searched for V2-apex germ line-targeting Envs among a large set of diverse primate lentiviruses and identified minimally modified versions of one chimpanzee SIV Env that bound several human V2-apex bNAb precursors and stimulated one of these in a V2-apex bNAb precursor-expressing knock-in mouse. We also generated chimeric simian-chimpanzee immunodeficiency viruses and showed that they elicit low-titer V2-directed heterologous plasma breadth in six of seven infected rhesus macaques. Characterization of this antibody response identified a new class of weakly cross-reactive neutralizing antibodies that target the V2-apex, but only in occluded-open Env trimers. The existence of this cryptic epitope, which in some Env backgrounds is immunodominant, needs to be considered in immunogen design.
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Affiliation(s)
- Frederic Bibollet-Ruche
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ronnie M. Russell
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Wenge Ding
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Weimin Liu
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Yingying Li
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Kshitij Wagh
- Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, New Mexico, USA
| | - Daniel Wrapp
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA
| | - Rumi Habib
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Vaccine and Immunotherapy Center, The Wistar Institute, Philadelphia, Pennsylvania, USA
- Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ashwin N. Skelly
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Vaccine and Immunotherapy Center, The Wistar Institute, Philadelphia, Pennsylvania, USA
- Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ryan S. Roark
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Scott Sherrill-Mix
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Shuyi Wang
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Juliette Rando
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Emily Lindemuth
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Kendra Cruickshank
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Younghoon Park
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Rachel Baum
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - John W. Carey
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Andrew Jesse Connell
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Hui Li
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Elena E. Giorgi
- Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, New Mexico, USA
| | - Ge S. Song
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, California, USA
| | - Shilei Ding
- Centre de Recherche du CHUM, Montreal, Quebec, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, Quebec, Canada
| | - Andrés Finzi
- Centre de Recherche du CHUM, Montreal, Quebec, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, Quebec, Canada
| | - Amanda Newman
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA
| | - Giovanna E. Hernandez
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA
| | - Emily Machiele
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA
| | - Derek W. Cain
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA
| | - Katayoun Mansouri
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, North Carolina, USA
| | | | - David C. Montefiori
- Department of Surgery, Duke University School of Medicine, Durham, North Carolina, USA
| | - Kevin J. Wiehe
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA
| | - S. Munir Alam
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA
| | - I-Ting Teng
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Peter D. Kwong
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Raiees Andrabi
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, California, USA
| | - Laurent Verkoczy
- San Diego Biomedical Research Institute, San Diego, California, USA
| | - Dennis R. Burton
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, California, USA
- Ragon Institute of MGH, Harvard and MIT, Cambridge, Massachusetts, USA
| | - Bette T. Korber
- Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, New Mexico, USA
| | - Kevin O. Saunders
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA
| | - Barton F. Haynes
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA
| | - Robert J. Edwards
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA
| | - George M. Shaw
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Beatrice H. Hahn
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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20
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Dam KMA, Fan C, Yang Z, Bjorkman PJ. Structural characterization of HIV-1 Env heterotrimers bound to one or two CD4 receptors reveals intermediate Env conformations. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.27.525985. [PMID: 36747804 PMCID: PMC9900888 DOI: 10.1101/2023.01.27.525985] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
HIV-1 envelope (Env) exhibits distinct conformational changes in response to host receptor (CD4) engagement. Env, a trimer of gp120/gp41 heterodimers, has been structurally characterized in a closed, prefusion conformation with closely associated gp120s and coreceptor binding sites on gp120 V3 hidden by V1V2 loops, and in fully-saturated CD4-bound open Env conformations with changes including outwardly rotated gp120s and displaced V1V2 loops. To investigate changes resulting from sub-stoichiometric CD4 binding, we solved 3.4Å and 3.9Å single-particle cryo-EM structures of soluble, native-like Envs bound to one or two CD4 molecules. Env trimer bound to one CD4 adopted the closed, prefusion Env state. When bound to two CD4s, the CD4-bound gp120s exhibited an open Env conformation including a four-stranded gp120 bridging sheet and displaced gp120 V1V2 loops that expose the coreceptor sites on V3. The third gp120 adopted an intermediate, occluded-open state that included gp120 outward rotation but maintained the prefusion, three-stranded gp120 bridging sheet and showed only partial V1V2 displacement and V3 exposure. We conclude that engagement of one CD4 molecule was insufficient to stimulate CD4-induced conformational changes, while binding two CD4 molecules led to Env opening in CD4-bound protomers only. Together, these results illuminate HIV-1 Env intermediate conformations and illustrate the structural plasticity of HIV-1 Env.
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Affiliation(s)
- Kim-Marie A Dam
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Chengcheng Fan
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Zhi Yang
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
- Present address: Department of Molecular and Cell Biology, University of California, 13 Berkeley, CA 94720, USA
| | - Pamela J Bjorkman
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
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Abstract
Human immunodeficiency virus type 1 (HIV-1) envelope (Env), a heterotrimer of gp120-gp41 subunits, mediates fusion of the viral and host cell membranes after interactions with the host receptor CD4 and a coreceptor. CD4 binding induces rearrangements in Env trimer, resulting in a CD4-induced (CD4i) open Env conformation. Structural studies of antibodies isolated from infected donors have defined antibody-Env interactions, with one class of antibodies specifically recognizing the CD4i open Env conformation. In this study, we characterized a group of monoclonal antibodies isolated from HIV-1 infected donors (V2i MAbs) that displayed characteristics of CD4i antibodies. Binding experiments demonstrated that the V2i MAbs preferentially recognize CD4-bound open Env trimers. Structural characterizations of V2i MAb-Env-CD4 trimer complexes using single-particle cryo-electron microscopy showed recognition by V2i MAbs using different angles of approach to the gp120 V1V2 domain and the β2/β3 strands on a CD4i open conformation Env with no direct interactions of the MAbs with CD4. We also characterized CG10, a CD4i antibody that was raised in mice immunized with a gp120-CD4 complex, bound to an Env trimer plus CD4. CG10 exhibited characteristics similar to those of the V2i antibodies, i.e., recognition of the open Env conformation, but showed direct contacts to both CD4 and gp120. Structural comparisons of these and previously characterized CD4i antibody interactions with Env provide a suggested mechanism for how these antibodies are elicited during HIV-1 infection. IMPORTANCE The RV144 HIV-1 clinical vaccination trial showed modest protection against viral infection. Antibody responses to the V1V2 region of HIV-1 Env gp120 were correlated inversely with the risk of infection, and data from three other clinical vaccine trials suggested a similar signal. In addition, antibodies targeting V1V2 have been correlated with protections from simian immunodeficiency virus (SIV) and simian-human immunodeficiency virus (SHIV) infections in nonhuman primates. We structurally characterized V2i antibodies directed against V1V2 isolated from HIV-1 infected humans in complex with open Env trimers bound to the host receptor CD4. We also characterized a CD4i antibody that interacts with CD4 as well as the gp120 subunit of an open Env trimer. Our study suggests how V2i and CD4i antibodies were elicited during HIV-1 infection.
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22
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Saunders KO, Edwards RJ, Tilahun K, Manne K, Lu X, Cain DW, Wiehe K, Williams WB, Mansouri K, Hernandez GE, Sutherland L, Scearce R, Parks R, Barr M, DeMarco T, Eater CM, Eaton A, Morton G, Mildenberg B, Wang Y, Rountree RW, Tomai MA, Fox CB, Moody MA, Alam SM, Santra S, Lewis MG, Denny TN, Shaw GM, Montefiori DC, Acharya P, Haynes BF. Stabilized HIV-1 envelope immunization induces neutralizing antibodies to the CD4bs and protects macaques against mucosal infection. Sci Transl Med 2022; 14:eabo5598. [PMID: 36070369 PMCID: PMC10034035 DOI: 10.1126/scitranslmed.abo5598] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
A successful HIV-1 vaccine will require induction of a polyclonal neutralizing antibody (nAb) response, yet vaccine-mediated induction of such a response in primates remains a challenge. We found that a stabilized HIV-1 CH505 envelope (Env) trimer formulated with a Toll-like receptor 7/8 agonist induced potent HIV-1 polyclonal nAbs that correlated with protection from homologous simian-human immunodeficiency virus (SHIV) infection. The serum dilution that neutralized 50% of virus replication (ID50 titer) required to protect 90% of macaques was 1:364 against the challenge virus grown in primary rhesus CD4+ T cells. Structural analyses of vaccine-induced nAbs demonstrated targeting of the Env CD4 binding site or the N156 glycan and the third variable loop base. Autologous nAb specificities similar to those elicited in macaques by vaccination were isolated from the human living with HIV from which the CH505 Env immunogen was derived. CH505 viral isolates were isolated that mutated the V1 to escape both the infection-induced and vaccine-induced antibodies. These results define the specificities of a vaccine-induced nAb response and the protective titers of HIV-1 vaccine-induced nAbs required to protect nonhuman primates from low-dose mucosal challenge by SHIVs bearing a primary transmitted/founder Env.
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Affiliation(s)
- Kevin O. Saunders
- Duke Human Vaccine Institute, Duke University Medical Center; Durham, NC 27710
- Department of Surgery, Duke University Medical Center; Durham, NC 27710
- Department of Microbiology and Molecular Genetics, Duke University Medical Center; Durham, NC 27710
- Department of Immunology, Duke University Medical Center; Durham, NC, 27710, USA
| | - Robert J. Edwards
- Duke Human Vaccine Institute, Duke University Medical Center; Durham, NC 27710
- Department of Medicine, Duke University Medical Center; Durham, NC, 27710, USA
| | - Kedamawit Tilahun
- Duke Human Vaccine Institute, Duke University Medical Center; Durham, NC 27710
- Department of Medicine, Duke University Medical Center; Durham, NC, 27710, USA
| | - Kartik Manne
- Duke Human Vaccine Institute, Duke University Medical Center; Durham, NC 27710
- Department of Medicine, Duke University Medical Center; Durham, NC, 27710, USA
| | - Xiaozhi Lu
- Duke Human Vaccine Institute, Duke University Medical Center; Durham, NC 27710
- Department of Medicine, Duke University Medical Center; Durham, NC, 27710, USA
| | - Derek W. Cain
- Duke Human Vaccine Institute, Duke University Medical Center; Durham, NC 27710
- Department of Medicine, Duke University Medical Center; Durham, NC, 27710, USA
| | - Kevin Wiehe
- Duke Human Vaccine Institute, Duke University Medical Center; Durham, NC 27710
- Department of Medicine, Duke University Medical Center; Durham, NC, 27710, USA
| | - Wilton B. Williams
- Duke Human Vaccine Institute, Duke University Medical Center; Durham, NC 27710
- Department of Surgery, Duke University Medical Center; Durham, NC 27710
- Department of Immunology, Duke University Medical Center; Durham, NC, 27710, USA
| | - Katayoun Mansouri
- Duke Human Vaccine Institute, Duke University Medical Center; Durham, NC 27710
- Department of Medicine, Duke University Medical Center; Durham, NC, 27710, USA
| | - Giovanna E. Hernandez
- Duke Human Vaccine Institute, Duke University Medical Center; Durham, NC 27710
- Department of Medicine, Duke University Medical Center; Durham, NC, 27710, USA
| | - Laura Sutherland
- Duke Human Vaccine Institute, Duke University Medical Center; Durham, NC 27710
- Department of Medicine, Duke University Medical Center; Durham, NC, 27710, USA
| | - Richard Scearce
- Duke Human Vaccine Institute, Duke University Medical Center; Durham, NC 27710
- Department of Medicine, Duke University Medical Center; Durham, NC, 27710, USA
| | - Robert Parks
- Duke Human Vaccine Institute, Duke University Medical Center; Durham, NC 27710
- Department of Medicine, Duke University Medical Center; Durham, NC, 27710, USA
| | - Maggie Barr
- Duke Human Vaccine Institute, Duke University Medical Center; Durham, NC 27710
- Department of Medicine, Duke University Medical Center; Durham, NC, 27710, USA
| | - Todd DeMarco
- Duke Human Vaccine Institute, Duke University Medical Center; Durham, NC 27710
- Department of Medicine, Duke University Medical Center; Durham, NC, 27710, USA
| | - Chloe M. Eater
- Duke Human Vaccine Institute, Duke University Medical Center; Durham, NC 27710
- Department of Medicine, Duke University Medical Center; Durham, NC, 27710, USA
| | - Amanda Eaton
- Duke Human Vaccine Institute, Duke University Medical Center; Durham, NC 27710
- Department of Surgery, Duke University Medical Center; Durham, NC 27710
| | | | | | - Yunfei Wang
- Duke Human Vaccine Institute, Duke University Medical Center; Durham, NC 27710
- Department of Medicine, Duke University Medical Center; Durham, NC, 27710, USA
| | - R. Wes Rountree
- Duke Human Vaccine Institute, Duke University Medical Center; Durham, NC 27710
- Department of Medicine, Duke University Medical Center; Durham, NC, 27710, USA
| | - Mark A. Tomai
- 3M Corporate Research Materials Lab, 3M Company; St. Paul, MN, 55144, USA
| | | | - M. Anthony Moody
- Duke Human Vaccine Institute, Duke University Medical Center; Durham, NC 27710
- Department of Pediatrics, Duke University Medical Center; Durham, NC, 27710, USA
| | - S. Munir Alam
- Duke Human Vaccine Institute, Duke University Medical Center; Durham, NC 27710
- Department of Medicine, Duke University Medical Center; Durham, NC, 27710, USA
| | - Sampa Santra
- Beth Israel Deaconess Medical Center; Boston, MA, 02215, USA
| | | | - Thomas N. Denny
- Duke Human Vaccine Institute, Duke University Medical Center; Durham, NC 27710
- Department of Medicine, Duke University Medical Center; Durham, NC, 27710, USA
| | - George M. Shaw
- Departments of Medicine and Microbiology, Perelman School of Medicine, University of Pennsylvania; Philadelphia, PA, 19104, USA
| | - David C. Montefiori
- Duke Human Vaccine Institute, Duke University Medical Center; Durham, NC 27710
- Department of Surgery, Duke University Medical Center; Durham, NC 27710
| | - Priyamvada Acharya
- Duke Human Vaccine Institute, Duke University Medical Center; Durham, NC 27710
- Department of Surgery, Duke University Medical Center; Durham, NC 27710
| | - Barton F. Haynes
- Duke Human Vaccine Institute, Duke University Medical Center; Durham, NC 27710
- Department of Immunology, Duke University Medical Center; Durham, NC, 27710, USA
- Department of Medicine, Duke University Medical Center; Durham, NC, 27710, USA
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Comparing methods for immobilizing HIV-1 SOSIPs in ELISAs that evaluate antibody binding. Sci Rep 2022; 12:11172. [PMID: 35778473 PMCID: PMC9247892 DOI: 10.1038/s41598-022-15506-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 06/24/2022] [Indexed: 11/09/2022] Open
Abstract
Enzyme-linked immunosorbent assays (ELISAs) are used to evaluate binding of broadly neutralizing antibodies (bNAbs) and polyclonal sera to native-like HIV-1 Env SOSIPs. Methods for immobilizing SOSIPs on plates differ, which can lead to variable or, in some cases, misleading results. Three methods used to immobilize SOSIPs were compared to determine how antigen immobilization methods affect Env conformation and ELISA results. HIV-1 SOSIPs were directly coated on polystyrene plates, captured by a monoclonal antibody against a C-terminal affinity tag, or randomly biotinylated and coated on a streptavidin plate. Binding of bNAbs with known epitopes were compared for each immobilization method. Binding of bNAbs targeting the V1V2, V3, CD4 binding site, and gp120/gp41 interface was comparable for all antigen immobilization methods. However, directly coated HIV-1 SOSIP ELISAs showed detectable binding of 17b, a CD4-induced antibody that binds a V3 epitope that is concealed on closed prefusion Env trimers in the absence of added CD4, whereas antibody-immobilized and randomly biotinylated Env-coated ELISAs did not show detectable binding of 17b in the absence of CD4. We conclude direct coating of HIV-1 SOSIPs on ELISA plates can result in exposure of CD4-induced antibody epitopes, suggesting disruption of Env structure and exposure of epitopes that are hidden in the closed, prefusion trimer.
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24
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Schapiro HM, Khasnis MD, Ahn K, Karagiaridi A, Hayden S, Cilento ME, Root MJ. Regulation of epitope exposure in the gp41 membrane-proximal external region through interactions at the apex of HIV-1 Env. PLoS Pathog 2022; 18:e1010531. [PMID: 35584191 PMCID: PMC9154124 DOI: 10.1371/journal.ppat.1010531] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 05/31/2022] [Accepted: 04/18/2022] [Indexed: 11/19/2022] Open
Abstract
Glycoprotein Env of human immunodeficiency virus type 1 (HIV-1) mediates viral entry through membrane fusion. Composed of gp120 and gp41 subunits arranged as a trimer-of-heterodimers, Env adopts a metastable, highly dynamic conformation on the virion surface. This structural plasticity limits the temporospatial exposure of many highly conserved, neutralizing epitopes, contributing to the difficulty in developing effective HIV-1 vaccines. Here, we employed antibody neutralization of HIV-1 infectivity to investigate how inter- and intra-gp120 interactions mediated by variable loops V1/V2 and V3 at the Env apex regulate accessibility of the gp41 membrane-proximal external region (MPER) at the Env base. Swapping the V3 loop from EnvSF162 into the EnvHXB2 background shifted MPER exposure from the prefusogenic state to a functional intermediate conformation that was distinct from the prehairpin-intermediate state sensitive to gp41-targeted fusion inhibitors. The V3-loop swap had a profound impact on global protein dynamics, biasing the equilibrium to a closed conformation resistant to most anti-gp120 antibodies, stabilizing the protein to both cold- and soluble CD4-induced Env inactivation, and increasing the CD4 requirements for viral entry. Further dissection of the EnvHXB2 V3 loop revealed that residue 306 uniquely modulated epitope exposure and trimer stability. The R306S substitution substantially decreased sensitivity to antibodies targeting the gp41 MPER and, surprisingly, the gp120 V3-loop crown (residues 312–315), but had only modest effects on exposure of intervening gp120 epitopes. Furthermore, the point mutation reduced soluble CD4-induced inactivation, but had no impact on cold inactivation. The residue appeared to exert its effects by electrostatically modifying the strength of intra-subunit interactions between the V1/V2 and V3 loops. The distinct patterns of neutralization and stability pointed to a novel prefusogenic Env conformation along the receptor activation pathway and suggested that apical Env-regulation of gp41 MPER exposure can be decoupled from much of the dynamics of gp120 subunits. Surface glycoprotein Env is the main target for neutralizing antibodies elicited by HIV-1 vaccines. Env spontaneously fluctuates among different structures, limiting exposure of many attractive antibody-binding epitopes and, thereby, confounding vaccine development. To characterize these fluctuations, we examined how exposure of the MPER epitope found at the base of Env is regulated by interactions of the V3 loop located in the apex. Starting with an extremely flexible Env with a readily-exposed MPER, we identified two alterations that substantially restricted antibody access to the epitope. The first, a wholesale swap of V3 loops between HIV-1 strains, energetically stabilized Env in a closed structure that restricted access to antibodies throughout the protein. The second, a point mutation that altered V3-loop charge, specifically destabilized the MPER-exposed conformation but had minimal impact on antibody access to Env regions in between the apex and base. The results indicate that MPER exposure is not explicitly tied to the dynamics of Env regions between the apex and base and suggest a new structural fluctuation during Env activation.
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Affiliation(s)
- Hannah M. Schapiro
- Department of Biochemistry and Molecular Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, United States of America
| | - Mukta D. Khasnis
- Department of Biochemistry and Molecular Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, United States of America
| | - Koree Ahn
- Department of Biochemistry and Molecular Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, United States of America
| | - Alexandra Karagiaridi
- Department of Biochemistry and Molecular Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, United States of America
| | - Stephanie Hayden
- Department of Biochemistry and Molecular Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, United States of America
| | - Maria E. Cilento
- Department of Biochemistry and Molecular Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, United States of America
| | - Michael J. Root
- Department of Microbial Infection and Immunity, The Ohio State University College of Medicine, Columbus, Ohio, United States of America
- * E-mail:
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25
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Abstract
The HIV Env glycoprotein is the surface glycoprotein responsible for viral entry into CD4+ immune cells. During infection, Env also serves as a primary target for antibody responses, which are robust but unable to control virus replication. Immune evasion by HIV-1 Env appears to employ complex mechanisms to regulate what antigenic states are presented to the immune system. Immunodominant features appear to be distinct from epitopes that interfere with Env functions in mediating infection. Further, cell-cell transmission studies indicate that vulnerable conformational states are additionally hidden from recognition on infected cells, even though the presence of Env at the cell surface is required for viral infection through the virological synapse. Cell-cell infection studies support that Env on infected cells is presented in distinct conformations from that on virus particles. Here we review data regarding the regulation of conformational states of Env and assess how regulated sorting of Env within the infected cell may underlie mechanisms to distinguish Env on the surface of virus particles versus Env on the surface of infected cells. These mechanisms may allow infected cells to avoid opsonization, providing cell-to-cell infection by HIV with a selective advantage during evolution within an infected individual. Understanding how distinct Env conformations are presented on cells versus viruses may be essential to designing effective vaccine approaches and therapeutic strategies to clear infected cell reservoirs.
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Affiliation(s)
- Connie Zhao
- Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Hongru Li
- Division of Infectious Diseases, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Talia H. Swartz
- Division of Infectious Diseases, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Benjamin K. Chen
- Division of Infectious Diseases, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA
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26
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Functional and Highly Cross-Linkable HIV-1 Envelope Glycoproteins Enriched in a Pretriggered Conformation. J Virol 2022; 96:e0166821. [PMID: 35343783 DOI: 10.1128/jvi.01668-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Binding to the receptor, CD4, drives the pretriggered, "closed" (state-1) conformation of the human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein (Env) trimer into more "open" conformations (states 2 and 3). Broadly neutralizing antibodies, which are elicited inefficiently, mostly recognize the state-1 Env conformation, whereas the more commonly elicited poorly neutralizing antibodies recognize states 2/3. HIV-1 Env metastability has created challenges for defining the state-1 structure and developing immunogens mimicking this labile conformation. The availability of functional state-1 Envs that can be efficiently cross-linked at lysine and/or acidic amino acid residues might assist these endeavors. To that end, we modified HIV-1AD8 Env, which exhibits an intermediate level of triggerability by CD4. We introduced lysine/acidic residues at positions that exhibit such polymorphisms in natural HIV-1 strains. Env changes that were tolerated with respect to gp120-gp41 processing, subunit association, and virus entry were further combined. Two common polymorphisms, Q114E and Q567K, as well as a known variant, A582T, additively rendered pseudoviruses resistant to cold, soluble CD4, and a CD4-mimetic compound, phenotypes indicative of stabilization of the pretriggered state-1 Env conformation. Combining these changes resulted in two lysine-rich HIV-1AD8 Env variants (E.2 and AE.2) with neutralization- and cold-resistant phenotypes comparable to those of natural, less triggerable tier 2/3 HIV-1 isolates. Compared with these and the parental Envs, the E.2 and AE.2 Envs were cleaved more efficiently and exhibited stronger gp120-trimer association in detergent lysates. These highly cross-linkable Envs enriched in a pretriggered conformation should assist characterization of the structure and immunogenicity of this labile state. IMPORTANCE The development of an efficient vaccine is critical for combating HIV-1 infection worldwide. However, the instability of the pretriggered shape (state 1) of the viral envelope glycoprotein (Env) makes it difficult to raise neutralizing antibodies against HIV-1. Here, by introducing multiple changes in Env, we derived two HIV-1 Env variants that are enriched in state 1 and can be efficiently cross-linked to maintain this shape. These Env complexes are more stable in detergent, assisting their purification. Thus, our study provides a path to a better characterization of the native pretriggered Env, which should assist vaccine development.
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27
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Global Increases in Human Immunodeficiency Virus Neutralization Sensitivity Due to Alterations in the Membrane-Proximal External Region of the Envelope Glycoprotein Can Be Minimized by Distant State 1-Stabilizing Changes. J Virol 2022; 96:e0187821. [PMID: 35289647 DOI: 10.1128/jvi.01878-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Binding to the receptor, CD4, drives the pretriggered, "closed" (State-1) conformation of the human immunodeficiency virus (HIV-1) envelope glycoprotein (Env) trimer ([gp120/gp41]3) into more "open" conformations. HIV-1 Env on the viral membrane is maintained in a State-1 conformation that resists binding and neutralization by commonly elicited antibodies. Premature triggering of Env before the virus engages a target cell typically leads to increased susceptibility to spontaneous inactivation or ligand-induced neutralization. Here, we showed that single amino acid substitutions in the gp41 membrane-proximal external region (MPER) of a primary HIV-1 strain resulted in viral phenotypes indicative of premature triggering of Env to downstream conformations. Specifically, the MPER changes reduced viral infectivity and globally increased virus sensitivity to poorly neutralizing antibodies, soluble CD4, a CD4-mimetic compound, and exposure to cold. In contrast, the MPER mutants exhibited decreased sensitivity to the State 1-preferring inhibitor, BMS-806, and to the PGT151 broadly neutralizing antibody. Depletion of cholesterol from virus particles did not produce the same State 1-destabilizing phenotypes as MPER alterations. Notably, State 1-stabilizing changes in Env distant from the MPER could minimize the phenotypic effects of MPER alteration but did not affect virus sensitivity to cholesterol depletion. Thus, membrane-proximal gp41 elements contribute to the maintenance of the pretriggered Env conformation. The conformationally disruptive effects of MPER changes can be minimized by distant State 1-stabilizing Env modifications, a strategy that may be useful in preserving the native pretriggered state of Env. IMPORTANCE The pretriggered shape of the human immunodeficiency virus (HIV-1) envelope glycoprotein (Env) is a major target for antibodies that can neutralize many strains of the virus. An effective HIV-1 vaccine may need to raise these types of antibodies, but this goal has proven difficult. One reason is that the pretriggered shape of Env is unstable and dependent on interactions near the viral membrane. Here, we showed that the membrane-proximal external region (MPER) of Env plays an important role in maintaining Env in a pretriggered shape. Alterations in the MPER resulted in global changes in Env conformation that disrupted its pretriggered shape. We also found that these disruptive effects of MPER changes could be minimized by distant Env modifications that stabilized the pretriggered shape. These modifications may be useful for preserving the native shape of Env for structural and vaccine studies.
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28
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Weiss S, Itri V, Pan R, Jiang X, Luo CC, Morris L, Malherbe DC, Barnette P, Alexander J, Kong XP, Haigwood NL, Hessell AJ, Duerr R, Zolla-Pazner S. Differential V2-directed antibody responses in non-human primates infected with SHIVs or immunized with diverse HIV vaccines. Nat Commun 2022; 13:903. [PMID: 35173151 PMCID: PMC8850611 DOI: 10.1038/s41467-022-28450-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 01/25/2022] [Indexed: 11/24/2022] Open
Abstract
V2p and V2i antibodies (Abs) that are specific for epitopes in the V1V2 region of the HIV gp120 envelope (Env) do not effectively neutralize HIV but mediate Fc-dependent anti-viral activities that have been correlated with protection from, or control of HIV, SIV and SHIV infections. Here, we describe a novel molecular toolbox that allows the discrimination of antigenically and functionally distinct polyclonal V2 Ab responses. We identify different patterns of V2 Ab induction by SHIV infection and three separate vaccine regimens that aid in fine-tuning an optimized immunization protocol for inducing V2p and V2i Abs. We observe no, or weak and sporadic V2p and V2i Abs in non-vaccinated SHIV-infected NHPs, but strong V2p and/or V2i Ab responses after immunization with a V2-targeting vaccine protocol. The V2-focused vaccination is superior to both natural infection and to immunization with whole Env constructs for inducing functional V2p- and V2i-specific responses. Strikingly, levels of V2-directed Abs correlate inversely with Abs specific for peptides of V3 and C5. These data demonstrate that a V1V2-targeting vaccine has advantages over the imprecise targeting of SIV/SHIV infections and of whole Env-based immunization regimens for inducing a more focused functional V2p- and V2i-specific Ab response. Here the authors show that an HIV vaccine in non-human primates that focuses antibodies on the V1V2 region of gp120 is superior to infection or immunization with whole envelope vaccines for inducing V1V2 antibodies with anti-viral functions that correlate with protection.
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Affiliation(s)
- Svenja Weiss
- Department of Medicine, Division of Infectious Diseases, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Vincenza Itri
- Department of Medicine, Division of Infectious Diseases, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Ruimin Pan
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY, USA
| | - Xunqing Jiang
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY, USA
| | - Christina C Luo
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY, USA
| | - Lynn Morris
- National Institute for Communicable Diseases, National Health Laboratory Service, Sandringham, Johannesburg, South Africa.,MRC Antibody Research Unit, University of the Witwatersrand, Johannesburg and Center for the AIDS Program of Research in South Africa, Johannesburg, South Africa
| | - Delphine C Malherbe
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, USA.,University of Texas Medical Branch, Department of Pathology, Galveston National Laboratory, Galveston, TX, USA
| | - Philip Barnette
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, USA
| | - Jeff Alexander
- PaxVax Corporation, Redwood City, CA, USA.,JL Alexander Research and Development Consulting LLC, San Diego, CA, USA
| | - Xiang-Peng Kong
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY, USA
| | - Nancy L Haigwood
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, USA
| | - Ann J Hessell
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, USA
| | - Ralf Duerr
- Department of Microbiology, New York University School of Medicine, New York, NY, USA
| | - Susan Zolla-Pazner
- Department of Medicine, Division of Infectious Diseases, Icahn School of Medicine at Mount Sinai, New York, NY, USA. .,Department of Microbiology, Icahn School of Medicine, New York, NY, USA.
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29
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Yang Z, Dam KMA, Bridges MD, Hoffmann MAG, DeLaitsch AT, Gristick HB, Escolano A, Gautam R, Martin MA, Nussenzweig MC, Hubbell WL, Bjorkman PJ. Neutralizing antibodies induced in immunized macaques recognize the CD4-binding site on an occluded-open HIV-1 envelope trimer. Nat Commun 2022; 13:732. [PMID: 35136084 PMCID: PMC8826976 DOI: 10.1038/s41467-022-28424-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 01/24/2022] [Indexed: 11/09/2022] Open
Abstract
Broadly-neutralizing antibodies (bNAbs) against HIV-1 Env can protect from infection. We characterize Ab1303 and Ab1573, heterologously-neutralizing CD4-binding site (CD4bs) antibodies, isolated from sequentially-immunized macaques. Ab1303/Ab1573 binding is observed only when Env trimers are not constrained in the closed, prefusion conformation. Fab-Env cryo-EM structures show that both antibodies recognize the CD4bs on Env trimer with an ‘occluded-open’ conformation between closed, as targeted by bNAbs, and fully-open, as recognized by CD4. The occluded-open Env trimer conformation includes outwardly-rotated gp120 subunits, but unlike CD4-bound Envs, does not exhibit V1V2 displacement, 4-stranded gp120 bridging sheet, or co-receptor binding site exposure. Inter-protomer distances within trimers measured by double electron-electron resonance spectroscopy suggest an equilibrium between occluded-open and closed Env conformations, consistent with Ab1303/Ab1573 binding stabilizing an existing conformation. Studies of Ab1303/Ab1573 demonstrate that CD4bs neutralizing antibodies that bind open Env trimers can be raised by immunization, thereby informing immunogen design and antibody therapeutic efforts. Neutralizing antibodies (bNAbs) against HIV-1 are exclusively directed against the viral envelope protein (Env) and mainly target Env in a closed, prefusion state. Here, Yang et al. structurally characterize two heterologously-neutralizing CD4-binding site (CD4bs) antibodies isolated from sequentially immunized macaques, and show that these antibodies recognize the CD4bs on Env trimers in an „occluded-open‟ conformation between closed, as targeted by bNAbs, and fully-open, as recognized by CD4.
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Affiliation(s)
- Zhi Yang
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Kim-Marie A Dam
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Michael D Bridges
- Jules Stein Eye Institute, University of California, Los Angeles, CA, USA.,Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA
| | - Magnus A G Hoffmann
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Andrew T DeLaitsch
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Harry B Gristick
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Amelia Escolano
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY, USA
| | - Rajeev Gautam
- Laboratory of Molecular Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Malcolm A Martin
- Laboratory of Molecular Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Michel C Nussenzweig
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY, USA.,Howard Hughes Medical Institute, The Rockefeller University, New York, NY, USA
| | - Wayne L Hubbell
- Jules Stein Eye Institute, University of California, Los Angeles, CA, USA.,Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA
| | - Pamela J Bjorkman
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA.
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30
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Carlon-Andres I, Malinauskas T, Padilla-Parra S. Structure dynamics of HIV-1 Env trimers on native virions engaged with living T cells. Commun Biol 2021; 4:1228. [PMID: 34707229 PMCID: PMC8551276 DOI: 10.1038/s42003-021-02658-1] [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: 12/23/2020] [Accepted: 09/09/2021] [Indexed: 11/29/2022] Open
Abstract
The HIV-1 envelope glycoprotein (Env) mediates viral entry into the host cell. Although the highly dynamic nature of Env intramolecular conformations has been shown with single molecule spectroscopy in vitro, the bona fide Env intra- and intermolecular mechanics when engaged with live T cells remains unknown. We used two photon fast fluorescence lifetime imaging detection of single-molecule Förster Resonance Energy Transfer occurring between fluorescent labels on HIV-1 Env on native virions. Our observations reveal Env dynamics at two levels: transitions between different intramolecular conformations and intermolecular interactions between Env within the viral membrane. Furthermore, we show that three broad neutralizing anti-Env antibodies directed to different epitopes restrict Env intramolecular dynamics and interactions between adjacent Env molecules when engaged with living T cells. Importantly, our results show that Env-Env interactions depend on efficient virus maturation, and that is disrupted upon binding of Env to CD4 or by neutralizing antibodies. Thus, this study illuminates how different intramolecular conformations and distribution of Env molecules mediate HIV-1 Env-T cell interactions in real time and therefore might control immune evasion.
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Affiliation(s)
- Irene Carlon-Andres
- Department of Infectious Diseases, King's College London, Faculty of Life Sciences & Medicine, London, United Kingdom.
- Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom.
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom.
| | - Tomas Malinauskas
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Sergi Padilla-Parra
- Department of Infectious Diseases, King's College London, Faculty of Life Sciences & Medicine, London, United Kingdom.
- Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom.
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom.
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31
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Abernathy ME, Gristick HB, Vielmetter J, Keeffe JR, Gnanapragasam PNP, Lee YE, Escolano A, Gautam R, Seaman MS, Martin MA, Nussenzweig MC, Bjorkman PJ. Antibody elicited by HIV-1 immunogen vaccination in macaques displaces Env fusion peptide and destroys a neutralizing epitope. NPJ Vaccines 2021; 6:126. [PMID: 34697307 PMCID: PMC8545924 DOI: 10.1038/s41541-021-00387-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 10/01/2021] [Indexed: 11/09/2022] Open
Abstract
HIV-1 vaccine design aims to develop an immunogen that elicits broadly neutralizing antibodies against a desired epitope, while eliminating responses to off-target regions of HIV-1 Env. We report characterization of Ab1245, an off-target antibody against the Env gp120-gp41 interface, from V3-glycan patch immunogen-primed and boosted macaques. A 3.7 Å cryo-EM structure of an Ab1245-Env complex reveals one Ab1245 Fab binding asymmetrically to Env trimer at the gp120-gp41 interface using its long CDRH3 to mimic regions of gp41. The mimicry includes positioning of a CDRH3 methionine into the gp41 tryptophan clasp, resulting in displacement of the fusion peptide and fusion peptide-proximal region. Despite fusion peptide displacement, Ab1245 is non-neutralizing even at high concentrations, raising the possibility that only two fusion peptides per trimer are required for viral-host membrane fusion. These structural analyses facilitate immunogen design to prevent elicitation of Ab1245-like antibodies that block neutralizing antibodies against the fusion peptide.
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Affiliation(s)
- Morgan E. Abernathy
- grid.20861.3d0000000107068890Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125 USA
| | - Harry B. Gristick
- grid.20861.3d0000000107068890Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125 USA
| | - Jost Vielmetter
- grid.20861.3d0000000107068890Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125 USA
| | - Jennifer R. Keeffe
- grid.20861.3d0000000107068890Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125 USA
| | - Priyanthi N. P. Gnanapragasam
- grid.20861.3d0000000107068890Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125 USA
| | - Yu E. Lee
- grid.20861.3d0000000107068890Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125 USA
| | | | - Rajeev Gautam
- grid.419681.30000 0001 2164 9667Laboratory of Molecular Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA ,grid.419681.30000 0001 2164 9667Present Address: Virology Branch, Basic Research Section, NIAID, NIH. 5601 Fisher’s Lane, Rockville, MD 20892 USA
| | - Michael S. Seaman
- grid.239395.70000 0000 9011 8547Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Boston, MA USA
| | - Malcolm A. Martin
- grid.419681.30000 0001 2164 9667Laboratory of Molecular Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Michel C. Nussenzweig
- Laboratory of Molecular Immunology, New York, 10065 USA ,grid.134907.80000 0001 2166 1519Howard Hughes Medical Institute, The Rockefeller University, New York, NY 10065 USA
| | - Pamela J. Bjorkman
- grid.20861.3d0000000107068890Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125 USA
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32
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Abernathy ME, Dam KMA, Esswein SR, Jette CA, Bjorkman PJ. How Antibodies Recognize Pathogenic Viruses: Structural Correlates of Antibody Neutralization of HIV-1, SARS-CoV-2, and Zika. Viruses 2021; 13:2106. [PMID: 34696536 PMCID: PMC8537525 DOI: 10.3390/v13102106] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 10/09/2021] [Accepted: 10/12/2021] [Indexed: 12/15/2022] Open
Abstract
The H1N1 pandemic of 2009-2010, MERS epidemic of 2012, Ebola epidemics of 2013-2016 and 2018-2020, Zika epidemic of 2015-2016, and COVID-19 pandemic of 2019-2021, are recent examples in the long history of epidemics that demonstrate the enormous global impact of viral infection. The rapid development of safe and effective vaccines and therapeutics has proven vital to reducing morbidity and mortality from newly emerging viruses. Structural biology methods can be used to determine how antibodies elicited during infection or vaccination target viral proteins and identify viral epitopes that correlate with potent neutralization. Here we review how structural and molecular biology approaches have contributed to our understanding of antibody recognition of pathogenic viruses, specifically HIV-1, SARS-CoV-2, and Zika. Determining structural correlates of neutralization of viruses has guided the design of vaccines, monoclonal antibodies, and small molecule inhibitors in response to the global threat of viral epidemics.
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Affiliation(s)
- Morgan E. Abernathy
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA; (M.E.A.); (K.-M.A.D.); (C.A.J.)
| | - Kim-Marie A. Dam
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA; (M.E.A.); (K.-M.A.D.); (C.A.J.)
| | - Shannon R. Esswein
- David Geffen School of Medicine at University of California, Los Angeles, CA 90095, USA;
| | - Claudia A. Jette
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA; (M.E.A.); (K.-M.A.D.); (C.A.J.)
| | - Pamela J. Bjorkman
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA; (M.E.A.); (K.-M.A.D.); (C.A.J.)
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33
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Kelow SP, Adolf-Bryfogle J, Dunbrack RL. Hiding in plain sight: structure and sequence analysis reveals the importance of the antibody DE loop for antibody-antigen binding. MAbs 2021; 12:1840005. [PMID: 33180672 PMCID: PMC7671036 DOI: 10.1080/19420862.2020.1840005] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Antibody variable domains contain “complementarity-determining regions” (CDRs), the loops that form the antigen binding site. CDRs1-3 are recognized as the canonical CDRs. However, a fourth loop sits adjacent to CDR1 and CDR2 and joins the D and E strands on the antibody v-type fold. This “DE loop” is usually treated as a framework region, even though mutations in the loop affect the conformation of the CDRs and residues in the DE loop occasionally contact antigen. We analyzed the length, structure, and sequence features of all DE loops in the Protein Data Bank (PDB), as well as millions of sequences from HIV-1 infected and naïve patients. We refer to the DE loop as H4 and L4 in the heavy and light chains, respectively. Clustering the backbone conformations of the most common length of L4 (6 residues) reveals four conformations: two κ-only clusters, one λ-only cluster, and one mixed κ/λ cluster. Most H4 loops are length-8 and exist primarily in one conformation; a secondary conformation represents a small fraction of H4-8 structures. H4 sequence variability exceeds that of the antibody framework in naïve human high-throughput sequences, and both L4 and H4 sequence variability from λ and heavy germline sequences exceed that of germline framework regions. Finally, we identified dozens of structures in the PDB with insertions in the DE loop, all related to broadly neutralizing HIV-1 antibodies (bNabs), as well as antibody sequences from high-throughput sequencing studies of HIV-infected individuals, illuminating a possible role in humoral immunity to HIV-1.
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Affiliation(s)
- Simon P Kelow
- Institute for Cancer Research, Fox Chase Cancer Center , Philadelphia, PA, USA.,Department of Biochemistry and Molecular Biophysics, University of Pennsylvania , Philadelphia, PA, USA
| | - Jared Adolf-Bryfogle
- Protein Design Lab, Institute for Protein Innovation , Boston, MA, USA.,Division of Hematology/Oncology, Boston Children's Hospital , Boston, MA, USA.,Department of Pediatrics, Harvard Medical School , Boston, MA, USA
| | - Roland L Dunbrack
- Institute for Cancer Research, Fox Chase Cancer Center , Philadelphia, PA, USA
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34
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HIV-1 entry: Duels between Env and host antiviral transmembrane proteins on the surface of virus particles. Curr Opin Virol 2021; 50:59-68. [PMID: 34390925 DOI: 10.1016/j.coviro.2021.07.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Revised: 07/20/2021] [Accepted: 07/21/2021] [Indexed: 12/18/2022]
Abstract
Human Immunodeficiency Virus type-1 (HIV-1) is the causative agent of AIDS. Its entry step is mediated by the envelope glycoprotein (Env). During the entry process, Env vastly changes its conformation. While non-liganded Env tends to have a closed structure, receptor-binding of Env opens its conformation, which leads to virus-cell membrane fusion. Single-molecule fluorescence resonance energy transfer (smFRET) imaging allows observation of these conformational changes on the virion surface. Nascent HIV-1 particles incorporate multiple host transmembrane proteins, some of which inhibit the entry process. The Env structure or its dynamics may determine the effectiveness of these antiviral mechanisms. Here, we review recent findings about the Env conformation changes on virus particles and inhibition of Env activities by virion-incorporated host transmembrane proteins.
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35
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Quaternary Interaction of the HIV-1 Envelope Trimer with CD4 and Neutralizing Antibodies. Viruses 2021; 13:v13071405. [PMID: 34372611 PMCID: PMC8310203 DOI: 10.3390/v13071405] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 07/13/2021] [Accepted: 07/15/2021] [Indexed: 11/25/2022] Open
Abstract
The entry of HIV-1 into host cells is initiated by the interaction of the viral envelope (Env) spike with the CD4 receptor. During this process, the spike undergoes a series of conformational changes that eventually lead to the exposure of the fusion peptide located at the N-terminus of the transmembrane glycoprotein, gp41. Recent structural and functional studies have provided important insights into the interaction of Env with CD4 at various stages. However, a fine elucidation of the earliest events of CD4 contact and its immediate effect on the Env conformation remains a challenge for investigation. Here, we summarize the discovery of the quaternary nature of the CD4-binding site in the HIV-1 Env and the role of quaternary contact in the functional interaction with the CD4 receptor. We propose two models for this initial contact based on the current knowledge and discuss how a better understanding of the quaternary interaction may lead to improved immunogens and antibodies targeting the CD4-binding site.
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36
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Sheng J, Wang S. Coevolutionary transitions emerging from flexible molecular recognition and eco-evolutionary feedback. iScience 2021; 24:102861. [PMID: 34401660 PMCID: PMC8353512 DOI: 10.1016/j.isci.2021.102861] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 05/16/2021] [Accepted: 07/13/2021] [Indexed: 01/16/2023] Open
Abstract
Highly mutable viruses evolve to evade host immunity that exerts selective pressure and adapts to viral dynamics. Here, we provide a framework for identifying key determinants of the mode and fate of viral-immune coevolution by linking molecular recognition and eco-evolutionary dynamics. We find that conservation level and initial diversity of antigen jointly determine the timing and efficacy of narrow and broad antibody responses, which in turn control the transition between viral persistence, clearance, and rebound. In particular, clearance of structurally complex antigens relies on antibody evolution in a larger antigenic space than where selection directly acts; viral rebound manifests binding-mediated feedback between ecology and rapid evolution. Finally, immune compartmentalization can slow viral escape but also delay clearance. This work suggests that flexible molecular binding allows a plastic phenotype that exploits potentiating neutral variations outside direct contact, opening new and shorter paths toward highly adaptable states. A scale-crossing framework identifies key determinants of viral-immune coevolution Fast specific response influences slow broad response by shaping antigen dynamics Antibody footprint shift enables breadth acquisition and viral clearance Model explains divergent kinetics and outcomes of HCV infection in humans
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Affiliation(s)
- Jiming Sheng
- Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Shenshen Wang
- Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, CA 90095, USA
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37
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Fischer W, Giorgi EE, Chakraborty S, Nguyen K, Bhattacharya T, Theiler J, Goloboff PA, Yoon H, Abfalterer W, Foley BT, Tegally H, San JE, de Oliveira T, Gnanakaran S, Korber B. HIV-1 and SARS-CoV-2: Patterns in the evolution of two pandemic pathogens. Cell Host Microbe 2021; 29:1093-1110. [PMID: 34242582 PMCID: PMC8173590 DOI: 10.1016/j.chom.2021.05.012] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Humanity is currently facing the challenge of two devastating pandemics caused by two very different RNA viruses: HIV-1, which has been with us for decades, and SARS-CoV-2, which has swept the world in the course of a single year. The same evolutionary strategies that drive HIV-1 evolution are at play in SARS-CoV-2. Single nucleotide mutations, multi-base insertions and deletions, recombination, and variation in surface glycans all generate the variability that, guided by natural selection, enables both HIV-1's extraordinary diversity and SARS-CoV-2's slower pace of mutation accumulation. Even though SARS-CoV-2 diversity is more limited, recently emergent SARS-CoV-2 variants carry Spike mutations that have important phenotypic consequences in terms of both antibody resistance and enhanced infectivity. We review and compare how these mutational patterns manifest in these two distinct viruses to provide the variability that fuels their evolution by natural selection.
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Affiliation(s)
- Will Fischer
- T-6: Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, New Mexico, 87545, USA; New Mexico Consortium, Los Alamos, New Mexico, 87545, USA
| | - Elena E Giorgi
- T-6: Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, New Mexico, 87545, USA; New Mexico Consortium, Los Alamos, New Mexico, 87545, USA
| | - Srirupa Chakraborty
- T-6: Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, New Mexico, 87545, USA; Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, New Mexico, 87545, USA
| | - Kien Nguyen
- T-6: Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, New Mexico, 87545, USA
| | - Tanmoy Bhattacharya
- T-2: Nuclear and Particle Physics, Astrophysics and Cosmology, Los Alamos National Laboratory, Los Alamos, New Mexico, 87545 USA
| | - James Theiler
- ISR-3: Space Data Science and Systems, Los Alamos National Laboratory, Los Alamos, New Mexico, 87545, USA
| | - Pablo A Goloboff
- Unidad Ejecutora Lillo, Consejo Nacional de Investigaciones Científicas y Técnicas - Fundación Miguel Lillo, S. M. de Tucumán, Miguel Lillo 251 4000, Argentina; Research Associate, American Museum of Natural History, New York 10024, USA
| | - Hyejin Yoon
- T-6: Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, New Mexico, 87545, USA
| | - Werner Abfalterer
- T-6: Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, New Mexico, 87545, USA
| | - Brian T Foley
- T-6: Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, New Mexico, 87545, USA
| | - Houriiyah Tegally
- KwaZulu-Natal Research Innovation and Sequencing Platform (KRISP), Department of Laboratory Medicine & Medical Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - James Emmanuel San
- KwaZulu-Natal Research Innovation and Sequencing Platform (KRISP), Department of Laboratory Medicine & Medical Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Tulio de Oliveira
- KwaZulu-Natal Research Innovation and Sequencing Platform (KRISP), Department of Laboratory Medicine & Medical Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Sandrasegaram Gnanakaran
- T-6: Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, New Mexico, 87545, USA
| | - Bette Korber
- T-6: Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, New Mexico, 87545, USA; New Mexico Consortium, Los Alamos, New Mexico, 87545, USA.
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38
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Species-Specific Valid Ternary Interactions of HIV-1 Env-gp120, CD4, and CCR5 as Revealed by an Adaptive Single-Amino Acid Substitution at the V3 Loop Tip. J Virol 2021; 95:e0217720. [PMID: 33883222 DOI: 10.1128/jvi.02177-20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Molecular interactions of the variable envelope gp120 subunit of HIV-1 with two cellular receptors are the first step of viral infection, thereby playing pivotal roles in determining viral infectivity and cell tropism. However, the underlying regulatory mechanisms for interactions under gp120 spontaneous variations largely remain unknown. Here, we show an allosteric mechanism in which a single gp120 mutation remotely controls the ternary interactions between gp120 and its receptors for the switch of viral cell tropism. Virological analyses showed that a G310R substitution at the tip of the gp120 V3 loop selectively abolished the viral replication ability in human cells, despite evoking enhancement of viral replication in macaque cells. Molecular dynamics (MD) simulations predicted that the G310R substitution at a site away from the CD4 interaction site selectively impeded the binding ability of gp120 to human CD4. Consistently, virions with the G310R substitution exhibited a reduced binding ability to human lymphocyte cells. Furthermore, the G310R substitution influenced the gp120-CCR5 interaction in a CCR5-type dependent manner as assessed by MD simulations and an infectivity assay using exogenously expressed CCR5s. Interestingly, an I198M mutation in human CCR5 restored the infectivity of the G310R virus in human cells. Finally, MD simulation predicted amino acid interplays that physically connect the V3 loop and gp120 elements for the CD4 and CCR5 interactions. Collectively, these results suggest that the V3 loop tip is a cis-allosteric regulator that remotely controls intra- and intermolecular interactions of HIV-1 gp120 for balancing ternary interactions with CD4 and CCR5. IMPORTANCE Understanding the molecular bases for viral entry into cells will lead to the elucidation of one of the major viral survival strategies, and thus to the development of new effective antiviral measures. As shown recently, HIV-1 is highly mutable and adaptable in growth-restrictive cells, such as those of macaque origin. HIV-1 initiates its infection by sequential interactions of Env-gp120 with two cell surface receptors, CD4 and CCR5. A recent epoch-making structural study has disclosed that CD4-induced conformation of gp120 is stabilized upon binding of CCR5 to the CD4-gp120 complex, whereas the biological significance of this remains totally unknown. Here, from a series of mutations found in our extensive studies, we identified a single-amino acid adaptive mutation at the V3 loop tip of Env-gp120 critical for its interaction with both CD4 and CCR5 in a host cell species-specific way. This remarkable finding could certainly provoke and accelerate studies to precisely clarify the HIV-1 entry mechanism.
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39
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Bennett AL, Henderson R. HIV-1 Envelope Conformation, Allostery, and Dynamics. Viruses 2021; 13:852. [PMID: 34067073 PMCID: PMC8150877 DOI: 10.3390/v13050852] [Citation(s) in RCA: 6] [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: 04/07/2021] [Revised: 04/28/2021] [Accepted: 05/04/2021] [Indexed: 11/16/2022] Open
Abstract
The HIV-1 envelope glycoprotein (Env) mediates host cell fusion and is the primary target for HIV-1 vaccine design. The Env undergoes a series of functionally important conformational rearrangements upon engagement of its host cell receptor, CD4. As the sole target for broadly neutralizing antibodies, our understanding of these transitions plays a critical role in vaccine immunogen design. Here, we review available experimental data interrogating the HIV-1 Env conformation and detail computational efforts aimed at delineating the series of conformational changes connecting these rearrangements. These studies have provided a structural mapping of prefusion closed, open, and transition intermediate structures, the allosteric elements controlling rearrangements, and state-to-state transition dynamics. The combination of these investigations and innovations in molecular modeling set the stage for advanced studies examining rearrangements at greater spatial and temporal resolution.
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Affiliation(s)
| | - Rory Henderson
- Duke Human Vaccine Institute, Durham, NC 27710, USA;
- Department of Medicine, Duke University, Durham, NC 27710, USA
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40
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HIV-1 Entry and Membrane Fusion Inhibitors. Viruses 2021; 13:v13050735. [PMID: 33922579 PMCID: PMC8146413 DOI: 10.3390/v13050735] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 04/13/2021] [Accepted: 04/21/2021] [Indexed: 12/14/2022] Open
Abstract
HIV-1 (human immunodeficiency virus type 1) infection begins with the attachment of the virion to a host cell by its envelope glycoprotein (Env), which subsequently induces fusion of viral and cell membranes to allow viral entry. Upon binding to primary receptor CD4 and coreceptor (e.g., chemokine receptor CCR5 or CXCR4), Env undergoes large conformational changes and unleashes its fusogenic potential to drive the membrane fusion. The structural biology of HIV-1 Env and its complexes with the cellular receptors not only has advanced our knowledge of the molecular mechanism of how HIV-1 enters the host cells but also provided a structural basis for the rational design of fusion inhibitors as potential antiviral therapeutics. In this review, we summarize our latest understanding of the HIV-1 membrane fusion process and discuss related therapeutic strategies to block viral entry.
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41
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Functional Anatomy of the Trimer Apex Reveals Key Hydrophobic Constraints That Maintain the HIV-1 Envelope Spike in a Closed State. mBio 2021; 12:mBio.00090-21. [PMID: 33785631 PMCID: PMC8092198 DOI: 10.1128/mbio.00090-21] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Elucidating the structure and function of the HIV-1 outer envelope proteins is critical for the design of an effective vaccine. Despite the availability of many high-resolution structures, key functional correlates in the envelope trimer remain undefined. The human immunodeficiency virus type 1 (HIV-1) envelope trimer maintains a closed, metastable configuration to protect vulnerable epitopes from neutralizing antibodies. Here, we identify key hydrophobic constraints at the trimer apex that function as global stabilizers of the HIV-1 envelope spike configuration. Mutation of individual residues within four hydrophobic clusters that fasten together the V1V2, V3, and C4 domains at the apex of gp120 dramatically increases HIV-1 sensitivity to weak and restricted neutralizing antibodies targeting epitopes that are largely concealed in the prefusion Env spike, consistent with the adoption of a partially open trimer configuration. Conversely, the same mutations decrease the sensitivity to broad and potent neutralizing antibodies that preferentially recognize the closed trimer. Sera from chronically HIV-infected patients neutralize open mutants with enhanced potency, compared to the wild-type virus, suggesting that a large fraction of host-generated antibodies target concealed epitopes. The identification of structural constraints that maintain the HIV-1 envelope in an antibody-protected state may inform the design of a protective vaccine.
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42
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Jette CA, Barnes CO, Kirk SM, Melillo B, Smith AB, Bjorkman PJ. Cryo-EM structures of HIV-1 trimer bound to CD4-mimetics BNM-III-170 and M48U1 adopt a CD4-bound open conformation. Nat Commun 2021; 12:1950. [PMID: 33782388 PMCID: PMC8007822 DOI: 10.1038/s41467-021-21816-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 02/11/2021] [Indexed: 02/01/2023] Open
Abstract
Human immunodeficiency virus-1 (HIV-1), the causative agent of AIDS, impacts millions of people. Entry into target cells is mediated by the HIV-1 envelope (Env) glycoprotein interacting with host receptor CD4, which triggers conformational changes allowing binding to a coreceptor and subsequent membrane fusion. Small molecule or peptide CD4-mimetic drugs mimic CD4's Phe43 interaction with Env by inserting into the conserved Phe43 pocket on Env subunit gp120. Here, we present single-particle cryo-EM structures of CD4-mimetics BNM-III-170 and M48U1 bound to a BG505 native-like Env trimer plus the CD4-induced antibody 17b at 3.7 Å and 3.9 Å resolution, respectively. CD4-mimetic-bound BG505 exhibits canonical CD4-induced conformational changes including trimer opening, formation of the 4-stranded gp120 bridging sheet, displacement of the V1V2 loop, and formation of a compact and elongated gp41 HR1C helical bundle. We conclude that CD4-induced structural changes on both gp120 and gp41 Env subunits are induced by binding to the gp120 Phe43 pocket.
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Affiliation(s)
- Claudia A. Jette
- grid.20861.3d0000000107068890Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA USA
| | - Christopher O. Barnes
- grid.20861.3d0000000107068890Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA USA
| | - Sharon M. Kirk
- grid.25879.310000 0004 1936 8972Department of Chemistry, University of Pennsylvania, Philadelphia, PA USA
| | - Bruno Melillo
- grid.25879.310000 0004 1936 8972Department of Chemistry, University of Pennsylvania, Philadelphia, PA USA
| | - Amos B. Smith
- grid.25879.310000 0004 1936 8972Department of Chemistry, University of Pennsylvania, Philadelphia, PA USA
| | - Pamela J. Bjorkman
- grid.20861.3d0000000107068890Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA USA
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43
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Ratnapriya S, Perez-Greene E, Schifanella L, Herschhorn A. Adjuvant-mediated enhancement of the immune response to HIV vaccines. FEBS J 2021; 289:3317-3334. [PMID: 33705608 DOI: 10.1111/febs.15814] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 01/28/2021] [Accepted: 03/08/2021] [Indexed: 12/26/2022]
Abstract
Protection from human immunodeficiency virus (HIV) acquisition will likely require an effective vaccine that elicits antibodies against the HIV-1 envelope glycoproteins (Envs), which are the sole target of neutralizing antibodies and a main focus of vaccine development. Adjuvants have been widely used to augment the magnitude and longevity of the adaptive immune responses to immunizations with HIV-1 Envs and to guide the development of specific immune responses. Here, we review the adjuvants that have been used in combination with HIV-1 Envs in several preclinical and human clinical trials in recent years. We summarize the interactions between the HIV-1 Envs and adjuvants, and highlight the routes of vaccine administration for various formulations. We then discuss the use of combinations of different adjuvants, the potential effect of adjuvants on the elicitation of antibodies enriched in somatic hypermutation and containing long complementarity-determining region 3 of the antibody heavy chain, and the elicitation of non-neutralizing antibodies.
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Affiliation(s)
- Sneha Ratnapriya
- Division of Infectious Diseases and International Medicine, Department of Medicine, University of Minnesota, Minneapolis, MN, USA
| | - Eva Perez-Greene
- Division of Infectious Diseases and International Medicine, Department of Medicine, University of Minnesota, Minneapolis, MN, USA
| | - Luca Schifanella
- Department of Surgery, Division of Surgical Outcomes and Precision Medicine Research, University of Minnesota Medical School, Minneapolis, MN, USA
| | - Alon Herschhorn
- Division of Infectious Diseases and International Medicine, Department of Medicine, University of Minnesota, Minneapolis, MN, USA.,Microbiology, Immunology, and Cancer Biology Graduate Program, University of Minnesota, Minneapolis, MN, USA.,The College of Veterinary Medicine Graduate Program, University of Minnesota, Minneapolis, MN, USA.,Institute for Molecular Virology, University of Minnesota, Minneapolis, MN, USA
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44
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Spencer DA, Malherbe DC, Vázquez Bernat N, Ádori M, Goldberg B, Dambrauskas N, Henderson H, Pandey S, Cheever T, Barnette P, Sutton WF, Ackerman ME, Kobie JJ, Sather DN, Karlsson Hedestam GB, Haigwood NL, Hessell AJ. Polyfunctional Tier 2-Neutralizing Antibodies Cloned following HIV-1 Env Macaque Immunization Mirror Native Antibodies in a Human Donor. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2021; 206:999-1012. [PMID: 33472907 PMCID: PMC7887735 DOI: 10.4049/jimmunol.2001082] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 12/24/2020] [Indexed: 11/19/2022]
Abstract
Vaccine efforts to combat HIV are challenged by the global diversity of viral strains and shielding of neutralization epitopes on the viral envelope glycoprotein trimer. Even so, the isolation of broadly neutralizing Abs from infected individuals suggests the potential for eliciting protective Abs through vaccination. This study reports a panel of 58 mAbs cloned from a rhesus macaque (Macaca mulatta) immunized with envelope glycoprotein immunogens curated from an HIV-1 clade C-infected volunteer. Twenty mAbs showed neutralizing activity, and the strongest neutralizer displayed 92% breadth with a median IC50 of 1.35 μg/ml against a 13-virus panel. Neutralizing mAbs predominantly targeted linear epitopes in the V3 region in the cradle orientation (V3C) with others targeting the V3 ladle orientation (V3L), the CD4 binding site (CD4bs), C1, C4, or gp41. Nonneutralizing mAbs bound C1, C5, or undetermined conformational epitopes. Neutralization potency strongly correlated with the magnitude of binding to infected primary macaque splenocytes and to the level of Ab-dependent cellular cytotoxicity, but did not predict the degree of Ab-dependent cellular phagocytosis. Using an individualized germline gene database, mAbs were traced to 23 of 72 functional IgHV alleles. Neutralizing V3C Abs displayed minimal nucleotide somatic hypermutation in the H chain V region (3.77%), indicating that relatively little affinity maturation was needed to achieve in-clade neutralization breadth. Overall, this study underscores the polyfunctional nature of vaccine-elicited tier 2-neutralizing V3 Abs and demonstrates partial reproduction of the human donor's humoral immune response through nonhuman primate vaccination.
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Affiliation(s)
- David A Spencer
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006
| | - Delphine C Malherbe
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006
| | - Néstor Vázquez Bernat
- Microbiology, Tumor and Cell Biology, Karolinska Institutet, 171 65 Solna, Stockholm, Sweden
| | - Monika Ádori
- Microbiology, Tumor and Cell Biology, Karolinska Institutet, 171 65 Solna, Stockholm, Sweden
| | | | - Nicholas Dambrauskas
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA 98109
| | - Heidi Henderson
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006
| | - Shilpi Pandey
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006
| | - Tracy Cheever
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006
| | - Philip Barnette
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006
| | - William F Sutton
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006
| | | | - James J Kobie
- Infectious Diseases, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294
| | - D Noah Sather
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA 98109
- Department of Pediatrics, University of Washington, Seattle, WA 98105; and
| | | | - Nancy L Haigwood
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006
- Molecular Microbiology and Immunology, School of Medicine, Oregon Health & Science University, Portland, OR 97239
| | - Ann J Hessell
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006;
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45
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Lu M. Single-Molecule FRET Imaging of Virus Spike-Host Interactions. Viruses 2021; 13:v13020332. [PMID: 33669922 PMCID: PMC7924862 DOI: 10.3390/v13020332] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 02/18/2021] [Accepted: 02/18/2021] [Indexed: 02/07/2023] Open
Abstract
As a major surface glycoprotein of enveloped viruses, the virus spike protein is a primary target for vaccines and anti-viral treatments. Current vaccines aiming at controlling the COVID-19 pandemic are mostly directed against the SARS-CoV-2 spike protein. To promote virus entry and facilitate immune evasion, spikes must be dynamic. Interactions with host receptors and coreceptors trigger a cascade of conformational changes/structural rearrangements in spikes, which bring virus and host membranes in proximity for membrane fusion required for virus entry. Spike-mediated viral membrane fusion is a dynamic, multi-step process, and understanding the structure–function-dynamics paradigm of virus spikes is essential to elucidate viral membrane fusion, with the ultimate goal of interventions. However, our understanding of this process primarily relies on individual structural snapshots of endpoints. How these endpoints are connected in a time-resolved manner, and the order and frequency of conformational events underlying virus entry, remain largely elusive. Single-molecule Förster resonance energy transfer (smFRET) has provided a powerful platform to connect structure–function in motion, revealing dynamic aspects of spikes for several viruses: SARS-CoV-2, HIV-1, influenza, and Ebola. This review focuses on how smFRET imaging has advanced our understanding of virus spikes’ dynamic nature, receptor-binding events, and mechanism of antibody neutralization, thereby informing therapeutic interventions.
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Affiliation(s)
- Maolin Lu
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT 06536, USA
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46
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Recombinant H7 hemagglutinin expressed in glycoengineered Pichia pastoris forms nanoparticles that protect mice from challenge with H7N9 influenza virus. Vaccine 2020; 38:7938-7948. [PMID: 33131935 DOI: 10.1016/j.vaccine.2020.10.061] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 10/15/2020] [Accepted: 10/19/2020] [Indexed: 01/10/2023]
Abstract
Cases of H7N9 human infection caused by an avian-origin H7N9 virus emerged in eastern China in 2013, leading to the urgent requirement of developing an effective vaccine to reduce its pandemic potential. In this report, the full-length recombinant H7 protein (rH7) of A/Hangzhou/1/2013 (H7N9) virus was expressed by a glycoengineered Pichia pastoris system. The rH7 protein underwent complex glycosylation modifications and polymerized to nanoparticles of 30-50 nm in diameter. Recombinant H7 (1.9 µg) elicited a > 1:40 hemagglutination inhibition titer, and 3.75 µg rH7 protected 100% of the mice in the mice challenge model with 10-fold 50% lethal dose of the A/Shanghai/2/2013 (H7N9) rat lung-adapted strain. In conclusion, rH7 produced by the glycoengineered P. pastoris can be used for vaccination against the H7N9 virus, and provides an effective platform for the rapid production of future influenza vaccines.
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The Bipartite Sequence Motif in the N and C Termini of gp85 of Subgroup J Avian Leukosis Virus Plays a Crucial Role in Receptor Binding and Viral Entry. J Virol 2020; 94:JVI.01232-20. [PMID: 32878894 DOI: 10.1128/jvi.01232-20] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 08/29/2020] [Indexed: 01/24/2023] Open
Abstract
Subgroup J avian leukemia virus (ALV-J), belonging to the genus Alpharetrovirus, enters cells through its envelope surface unit (gp85) via specifically recognizing the cellular receptor chicken Na+/H+ exchanger type I (chNHE1), the 28 to 39 N-terminal residues of which were characterized as the minimal receptor functional domain in our previous studies. In this study, to further clarify the precise organization and properties of the interaction between ALV-J gp85 and chNHE1, we identified the chNHE1-binding domain of ALV-J gp85 using a series of gp85 mutants with segment substitutions and evaluating their effects on chNHE1 binding in protein-cell binding assays. Our results showed that hemagglutinin (HA) substitutions of amino acids (aa) 38 to 131 (N terminus of gp85) and aa 159 to 283 (C terminus of gp85) significantly inhibited the interaction between gp85 and chNHE1/chNHE1 loop 1. In addition, these HA-substituted chimeric gp85 proteins could not effectively block the entry of ALV-J into chNHE1-expressing cells. Furthermore, analysis of various N-linked glycosylation sites and cysteine mutants in gp85 revealed that glycosylation sites (N6 and N11) and cysteines (C3 and C9) were directly involved in receptor-gp85 binding and important for the entry of ALV-J into cells. Taken together, our findings indicated that the bipartite sequence motif, spanning aa 38 to 131 and aa 159 to 283, of ALV-J gp85 was essential for binding to chNHE1, with its two N-linked glycosylation sites and two cysteines being important for its receptor-binding function and subsequent viral infection steps.IMPORTANCE Infection of a cell by retroviruses requires the attachment and fusion of the host and viral membranes. The specific adsorption of envelope (Env) surface proteins to cell receptors is a key step in triggering infections and has been the target of antiviral drug screening. ALV-J is an economically important avian pathogen that belongs to the genus Alpharetrovirus and has a wider host range than other ALV subgroups. Our results showed that the amino acids 38 to 131 of the N terminus and 159 to 283 of the C terminus of ALV-J gp85 controlled the efficiency of gp85 binding to chNHE1 and were critical for viral infection. In addition, the glycosylation sites (N6 and N11) and cysteines (C3 and C9) of gp85 played a crucial role in the receptor binding and viral entry. These findings might help elucidate the mechanism of the entry of ALV-J into host cells and provide antiviral targets for the control of ALV-J.
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Yan L, Wang S. Shaping Polyclonal Responses via Antigen-Mediated Antibody Interference. iScience 2020; 23:101568. [PMID: 33083735 PMCID: PMC7530306 DOI: 10.1016/j.isci.2020.101568] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 06/29/2020] [Accepted: 09/14/2020] [Indexed: 12/05/2022] Open
Abstract
Broadly neutralizing antibodies (bnAbs) recognize conserved features of rapidly mutating pathogens and confer universal protection, but they emerge rarely in natural infection. Increasing evidence indicates that seemingly passive antibodies may interfere with natural selection of B cells. Yet, how such interference modulates polyclonal responses is unknown. Here we provide a framework for understanding the role of antibody interference—mediated by multi-epitope antigens—in shaping B cell clonal makeup and the fate of bnAb lineages. We find that, under heterogeneous interference, clones with different intrinsic fitness can collectively persist. Furthermore, antagonism among fit clones (specific for variable epitopes) promotes expansion of unfit clones (targeting conserved epitopes), at the cost of repertoire potency. This trade-off, however, can be alleviated by synergy toward the unfit. Our results provide a physical basis for antigen-mediated clonal interactions, stress system-level impacts of molecular synergy and antagonism, and offer principles to amplify naturally rare clones. Multi-epitope antigens mediate antibody interference that couples B cell lineages Trade-off exists between repertoire potency and persistence of broad lineages Antigen-mediated synergy toward intrinsically unfit clones alleviates the trade-off Amplifying rare clones by leveraging molecular interference structure
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Affiliation(s)
- Le Yan
- Chan Zuckerberg Biohub, 499 Illinois Street, San Francisco, CA 94158, USA
| | - Shenshen Wang
- Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, CA 90095, USA
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Lu M, Ma X, Reichard N, Terry DS, Arthos J, Smith AB, Sodroski JG, Blanchard SC, Mothes W. Shedding-Resistant HIV-1 Envelope Glycoproteins Adopt Downstream Conformations That Remain Responsive to Conformation-Preferring Ligands. J Virol 2020; 94:e00597-20. [PMID: 32522853 PMCID: PMC7431789 DOI: 10.1128/jvi.00597-20] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 06/05/2020] [Indexed: 12/25/2022] Open
Abstract
The human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein (Env) trimer of gp120-gp41 heterodimers mediates virus entry into CD4-positive (CD4+) cells. Single-molecule fluorescence resonance energy transfer (smFRET) has revealed that native Env on the surface of viruses predominantly exists in a pretriggered conformation (state 1) that is preferentially recognized by many broadly neutralizing antibodies (bNAbs). Env is activated by binding receptor CD4, which drives transitions through a default intermediate conformation (state 2) into the three-CD4-bound open conformation (state 3). The application of smFRET to assess the conformational state of existing Env constructs and ligand complexes recently revealed that all current high-resolution structures correspond to downstream states 2 and 3. The structure of state 1, therefore, remains unknown. We sought to identify conditions whereby HIV-1 Env could be stabilized in the pretriggered state 1 for possible structural characterization. Shedding of gp120, known to severely complicate structural studies, can be prevented by using the uncleaved gp160JR-FL precursor with alterations in the protease cleavage site (R508S/R511S) or by introducing a disulfide bridge between gp120 and gp41 designated "SOS" (A501C/T605C). smFRET demonstrated that both shedding-preventing modifications shifted the conformational landscape of Env downstream toward states 2 and 3. However, both membrane-bound Env proteins on the surface of intact viruses remained conformationally dynamic, responsive to state-stabilizing ligands, and able to be stabilized in state 1 by specific ligands such as the Bristol-Myers Squibb (BMS) entry inhibitors. The here-described identification of state 1-stabilizing conditions may enable structural characterization of the state 1 conformation of HIV-1 Env.IMPORTANCE The HIV-1 envelope glycoprotein (Env) opens in response to receptor CD4 binding from a pretriggered (state 1) conformation through a necessary intermediate to the three-CD4-bound conformation. The application of smFRET to test the conformational state of existing Env constructs and ligand complexes used for high-resolution structures recently revealed that they correspond to the downstream conformations. The structure of the pretriggered Env conformation, preferentially recognized by broadly neutralizing antibodies, remains unknown. Here, we identify experimental conditions that stabilize membrane-bound and shedding-resistant virus Env trimers in state 1, potentially facilitating structural characterization of this unknown conformational state.
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Affiliation(s)
- Maolin Lu
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Xiaochu Ma
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Nick Reichard
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Daniel S Terry
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - James Arthos
- Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Amos B Smith
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Joseph G Sodroski
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA
| | - Scott C Blanchard
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Walther Mothes
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, Connecticut, USA
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50
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Li Z, Li W, Lu M, Bess J, Chao CW, Gorman J, Terry DS, Zhang B, Zhou T, Blanchard SC, Kwong PD, Lifson JD, Mothes W, Liu J. Subnanometer structures of HIV-1 envelope trimers on aldrithiol-2-inactivated virus particles. Nat Struct Mol Biol 2020; 27:726-734. [PMID: 32601441 PMCID: PMC8138683 DOI: 10.1038/s41594-020-0452-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Accepted: 05/18/2020] [Indexed: 12/12/2022]
Abstract
The HIV-1 envelope glycoprotein (Env) trimer, composed of gp120 and gp41 subunits, mediates viral entry into cells. Recombinant Env trimers have been studied structurally, but characterization of Env embedded in intact virus membranes has been limited to low resolution. Here, we deploy cryo-electron tomography and subtomogram averaging to determine the structures of Env trimers on aldrithiol-2 (AT-2)-inactivated virions in ligand-free, antibody-bound and CD4-bound forms at subnanometer resolution. Tomographic reconstructions document molecular features consistent with high-resolution structures of engineered soluble and detergent-solubilized Env trimers. One of three conformational states previously predicted by smFRET was not observed by cryo-ET, potentially owing to AT-2 inactivation. We did observe Env trimers to open in situ in response to CD4 binding, with an outward movement of gp120-variable loops and an extension of a critical gp41 helix. Overall features of Env trimer embedded in AT-2-treated virions appear well-represented by current engineered trimers.
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Affiliation(s)
- Ze Li
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT, USA
- Microbial Sciences Institute, Yale University, West Haven, CT, USA
- Fudan University Shanghai Cancer Center, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai, China
| | - Wenwei Li
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT, USA
- Microbial Sciences Institute, Yale University, West Haven, CT, USA
| | - Maolin Lu
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT, USA
| | - Julian Bess
- AIDS and Cancer Virus Program, Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Cara W Chao
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Jason Gorman
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Daniel S Terry
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Baoshan Zhang
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Tongqing Zhou
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Scott C Blanchard
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Peter D Kwong
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Jeffrey D Lifson
- AIDS and Cancer Virus Program, Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Walther Mothes
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT, USA.
| | - Jun Liu
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT, USA.
- Microbial Sciences Institute, Yale University, West Haven, CT, USA.
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