1
|
Natali EN, Horst A, Meier P, Greiff V, Nuvolone M, Babrak LM, Fink K, Miho E. The dengue-specific immune response and antibody identification with machine learning. NPJ Vaccines 2024; 9:16. [PMID: 38245547 PMCID: PMC10799860 DOI: 10.1038/s41541-023-00788-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 12/07/2023] [Indexed: 01/22/2024] Open
Abstract
Dengue virus poses a serious threat to global health and there is no specific therapeutic for it. Broadly neutralizing antibodies recognizing all serotypes may be an effective treatment. High-throughput adaptive immune receptor repertoire sequencing (AIRR-seq) and bioinformatic analysis enable in-depth understanding of the B-cell immune response. Here, we investigate the dengue antibody response with these technologies and apply machine learning to identify rare and underrepresented broadly neutralizing antibody sequences. Dengue immunization elicited the following signatures on the antibody repertoire: (i) an increase of CDR3 and germline gene diversity; (ii) a change in the antibody repertoire architecture by eliciting power-law network distributions and CDR3 enrichment in polar amino acids; (iii) an increase in the expression of JNK/Fos transcription factors and ribosomal proteins. Furthermore, we demonstrate the applicability of computational methods and machine learning to AIRR-seq datasets for neutralizing antibody candidate sequence identification. Antibody expression and functional assays have validated the obtained results.
Collapse
Affiliation(s)
- Eriberto Noel Natali
- FHNW University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences, Muttenz, Switzerland
| | - Alexander Horst
- FHNW University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences, Muttenz, Switzerland
| | - Patrick Meier
- FHNW University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences, Muttenz, Switzerland
| | - Victor Greiff
- Department of Immunology, Oslo University Hospital Rikshospitalet and University of Oslo, Oslo, Norway
| | - Mario Nuvolone
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Lmar Marie Babrak
- FHNW University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences, Muttenz, Switzerland
| | | | - Enkelejda Miho
- FHNW University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences, Muttenz, Switzerland.
- SIB Swiss Institute of Bioinformatics, Lausanne, Switzerland.
- aiNET GmbH, Basel, Switzerland.
| |
Collapse
|
2
|
Munt JE, Henein S, Adams C, Young E, Hou YJ, Conrad H, Zhu D, Dong S, Kose N, Yount B, Meganck RM, Tse LPV, Kuan G, Balmaseda A, Ricciardi MJ, Watkins DI, Crowe JE, Harris E, DeSilva AM, Baric RS. Homotypic antibodies target novel E glycoprotein domains after natural DENV 3 infection/vaccination. Cell Host Microbe 2023; 31:1850-1865.e5. [PMID: 37909048 PMCID: PMC11221912 DOI: 10.1016/j.chom.2023.10.004] [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: 03/01/2023] [Revised: 07/31/2023] [Accepted: 10/04/2023] [Indexed: 11/02/2023]
Abstract
The envelope (E) glycoprotein is the primary target of type-specific (TS) neutralizing antibodies (nAbs) after infection with any of the four distinct dengue virus serotypes (DENV1-4). nAbs can be elicited to distinct structural E domains (EDs) I, II, or III. However, the relative contribution of these domain-specific antibodies is unclear. To identify the primary DENV3 nAb targets in sera after natural infection or vaccination, chimeric DENV1 recombinant encoding DENV3 EDI, EDII, or EDIII were generated. DENV3 EDII is the principal target of TS polyclonal nAb responses and encodes two or more neutralizing epitopes. In contrast, some were individuals vaccinated with a DENV3 monovalent vaccine-elicited serum TS nAbs targeting each ED in a subject-dependent fashion, with an emphasis on EDI and EDIII. Vaccine responses were also sensitive to DENV3 genotypic variation. This DENV1/3 panel allows the measurement of serum ED TS nAbs, revealing differences in TS nAb immunity after natural infection or vaccination.
Collapse
Affiliation(s)
- Jennifer E Munt
- Department of Epidemiology, University of North Carolina, Chapel Hill, NC, USA
| | - Sandra Henein
- Department of Microbiology and Immunology, University of North Carolina, Chapel Hill, NC, USA
| | - Cameron Adams
- Department of Microbiology and Immunology, University of North Carolina, Chapel Hill, NC, USA
| | - Ellen Young
- Department of Epidemiology, University of North Carolina, Chapel Hill, NC, USA
| | - Yixuan J Hou
- Department of Epidemiology, University of North Carolina, Chapel Hill, NC, USA
| | - Helen Conrad
- Department of Epidemiology, University of North Carolina, Chapel Hill, NC, USA
| | - Deanna Zhu
- Department of Epidemiology, University of North Carolina, Chapel Hill, NC, USA
| | - Stephanie Dong
- Department of Epidemiology, University of North Carolina, Chapel Hill, NC, USA
| | - Nurgun Kose
- Vanderbilt Vaccine Center, Nashville, TN, USA
| | - Boyd Yount
- Department of Epidemiology, University of North Carolina, Chapel Hill, NC, USA
| | - Rita M Meganck
- Department of Epidemiology, University of North Carolina, Chapel Hill, NC, USA
| | - Long Ping V Tse
- Department of Epidemiology, University of North Carolina, Chapel Hill, NC, USA
| | - Guillermina Kuan
- Health Center Socrates Flores Vivas, Ministry of Health, Managua, Nicaragua; Sustainable Sciences Institute, Managua, Nicaragua
| | - Angel Balmaseda
- Sustainable Sciences Institute, Managua, Nicaragua; National Virology Laboratory, National Center for Diagnosis and Reference, Ministry of Health, Managua, Nicaragua
| | | | - David I Watkins
- University of Massachusetts Medical School, Worcester, MA, USA
| | | | - Eva Harris
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California Berkeley, Berkeley, CA, USA
| | - Aravinda M DeSilva
- Department of Microbiology and Immunology, University of North Carolina, Chapel Hill, NC, USA
| | - Ralph S Baric
- Department of Epidemiology, University of North Carolina, Chapel Hill, NC, USA; Department of Microbiology and Immunology, University of North Carolina, Chapel Hill, NC, USA.
| |
Collapse
|
3
|
Ooi EE, Kalimuddin S. Insights into dengue immunity from vaccine trials. Sci Transl Med 2023; 15:eadh3067. [PMID: 37437017 DOI: 10.1126/scitranslmed.adh3067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 06/08/2023] [Indexed: 07/14/2023]
Abstract
The quest for an effective dengue vaccine has culminated in two approved vaccines and another that has completed phase 3 clinical trials. However, shortcomings exist in each, suggesting that the knowledge on dengue immunity used to develop these vaccines was incomplete. Vaccine trial findings could refine our understanding of dengue immunity, because these are experimentally derived, placebo-controlled data. Results from these trials suggest that neutralizing antibody titers alone are insufficient to inform protection against symptomatic infection, implicating a role for cellular immunity in protection. These findings have relevance for both future dengue vaccine development and application of current vaccines for maximal public health benefit.
Collapse
Affiliation(s)
- Eng Eong Ooi
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore 169857, Singapore
- Viral Research and Experimental Medicine Centre, SingHealth Duke-NUS Academic Medical Centre, Singapore 169857, Singapore
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore 117549, Singapore
| | - Shirin Kalimuddin
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore 169857, Singapore
- Department of Infectious Diseases, Singapore General Hospital, Singapore 169856, Singapore
| |
Collapse
|
4
|
Sarker A, Dhama N, Gupta RD. Dengue virus neutralizing antibody: a review of targets, cross-reactivity, and antibody-dependent enhancement. Front Immunol 2023; 14:1200195. [PMID: 37334355 PMCID: PMC10272415 DOI: 10.3389/fimmu.2023.1200195] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 05/19/2023] [Indexed: 06/20/2023] Open
Abstract
Dengue is the most common viral infection spread by mosquitoes, prevalent in tropical countries. The acute dengue virus (DENV) infection is a benign and primarily febrile illness. However, secondary infection with alternative serotypes can worsen the condition, leading to severe and potentially fatal dengue. The antibody raised by the vaccine or the primary infections are frequently cross-reactive; however, weakly neutralizing, and during subsequent infection, they may increase the odds of antibody-dependent enhancement (ADE). Despite that, many neutralizing antibodies have been identified against the DENV, which are thought to be useful in reducing dengue severity. Indeed, an antibody must be free from ADE for therapeutic application, as it is pretty common in dengue infection and escalates disease severity. Therefore, this review has described the critical characteristics of DENV and the potential immune targets in general. The primary emphasis is given to the envelope protein of DENV, where potential epitopes targeted for generating serotype-specific and cross-reactive antibodies have critically been described. In addition, a novel class of highly neutralizing antibodies targeted to the quaternary structure, similar to viral particles, has also been described. Lastly, we have discussed different aspects of the pathogenesis and ADE, which would provide significant insights into developing safe and effective antibody therapeutics and equivalent protein subunit vaccines.
Collapse
|
5
|
Wilken L, Stelz S, Agac A, Sutter G, Prajeeth CK, Rimmelzwaan GF. Recombinant Modified Vaccinia Virus Ankara Expressing a Glycosylation Mutant of Dengue Virus NS1 Induces Specific Antibody and T-Cell Responses in Mice. Vaccines (Basel) 2023; 11:vaccines11040714. [PMID: 37112626 PMCID: PMC10140942 DOI: 10.3390/vaccines11040714] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 03/20/2023] [Accepted: 03/21/2023] [Indexed: 04/29/2023] Open
Abstract
The four serotypes of dengue virus (DENV1-4) continue to pose a major public health threat. The first licenced dengue vaccine, which expresses the surface proteins of DENV1-4, has performed poorly in immunologically naïve individuals, sensitising them to antibody-enhanced dengue disease. DENV non-structural protein 1 (NS1) can directly induce vascular leakage, the hallmark of severe dengue disease, which is blocked by NS1-specific antibodies, making it an attractive target for vaccine development. However, the intrinsic ability of NS1 to trigger vascular leakage is a potential drawback of its use as a vaccine antigen. Here, we modified DENV2 NS1 by mutating an N-linked glycosylation site associated with NS1-induced endothelial hyperpermeability and used modified vaccinia virus Ankara (MVA) as a vector for its delivery. The resulting construct, rMVA-D2-NS1-N207Q, displayed high genetic stability and drove efficient secretion of NS1-N207Q from infected cells. Secreted NS1-N207Q was composed of dimers and lacked N-linked glycosylation at position 207. Prime-boost immunisation of C57BL/6J mice induced high levels of NS1-specific antibodies binding various conformations of NS1 and elicited NS1-specific CD4+ T-cell responses. Our findings support rMVA-D2-NS1-N207Q as a promising and potentially safer alternative to existing NS1-based vaccine candidates, warranting further pre-clinical testing in a relevant mouse model of DENV infection.
Collapse
Affiliation(s)
- Lucas Wilken
- Research Center for Emerging Infections and Zoonoses (RIZ), University of Veterinary Medicine (TiHo), 30559 Hannover, Germany
| | - Sonja Stelz
- Research Center for Emerging Infections and Zoonoses (RIZ), University of Veterinary Medicine (TiHo), 30559 Hannover, Germany
| | - Ayse Agac
- Research Center for Emerging Infections and Zoonoses (RIZ), University of Veterinary Medicine (TiHo), 30559 Hannover, Germany
| | - Gerd Sutter
- Division of Virology, Institute for Infectious Diseases and Zoonoses, Department of Veterinary Sciences, Ludwig Maximilian University (LMU), 80539 Munich, Germany
| | - Chittappen Kandiyil Prajeeth
- Research Center for Emerging Infections and Zoonoses (RIZ), University of Veterinary Medicine (TiHo), 30559 Hannover, Germany
| | - Guus F Rimmelzwaan
- Research Center for Emerging Infections and Zoonoses (RIZ), University of Veterinary Medicine (TiHo), 30559 Hannover, Germany
| |
Collapse
|
6
|
Lu J, Chen L, Du P, Guo J, Wang X, Jiang Y, Yu Y, Wang R, Yang Z. A human monoclonal antibody to neutralize all four serotypes of dengue virus derived from patients at the convalescent phase of infection. Virology 2022; 576:74-82. [PMID: 36183498 DOI: 10.1016/j.virol.2022.09.007] [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: 05/06/2022] [Revised: 09/12/2022] [Accepted: 09/18/2022] [Indexed: 11/16/2022]
Abstract
Dengue virus (DENV) is a prevalent mosquito-transmitted human pathogen, causing about 100 million cases of acute dengue fever and 21,000 deaths annually worldwide. Therapeutic neutralizing antibodies against dengue virus might be effective to treat severe dengue fever. Here, we showed that human monoclonal antibody (HMAb) 9C7 bound to all four intact serotypes of DENV but not to the recombinant envelope protein, suggesting HMAb 9C7 recognized a conformational epitope of the envelope protein. Taken together our results suggested that HMAb 9C7 neutralized all four serotypes of DENV in vitro and, for DENV-1, indicated activity at the pre- and post-attachment steps in the viral life cycle. HMAb 9C7 potently protected suckling mice from lethal challenge with all four serotypes of DENV. FcγRII-mediated uptake of immune complexes and antibody-dependent enhancement at low doses of the antibody were abolished by two Leu-to-Ala (9C7-LALA) mutations or deletion of nine amino acids (9C7-9del) in HMAb 9C7 Fc. Therefore, HMAb 9C7 represented a promising prophylactic and therapeutic agent against all four serotypes of DENV.
Collapse
Affiliation(s)
- Jiansheng Lu
- Laboratory of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China
| | - Lei Chen
- Laboratory of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China
| | - Peng Du
- Laboratory of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China
| | - Jiazheng Guo
- Laboratory of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China
| | - Xi Wang
- Laboratory of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China
| | - Yujia Jiang
- Laboratory of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China
| | - Yunzhou Yu
- Laboratory of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China.
| | - Rong Wang
- Laboratory of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China.
| | - Zhixin Yang
- Laboratory of Protein Engineering, Beijing Institute of Biotechnology, Beijing, China.
| |
Collapse
|
7
|
Kaushik V, G SK, Gupta LR, Kalra U, Shaikh AR, Cavallo L, Chawla M. Immunoinformatics Aided Design and In-Vivo Validation of a Cross-Reactive Peptide Based Multi-Epitope Vaccine Targeting Multiple Serotypes of Dengue Virus. Front Immunol 2022; 13:865180. [PMID: 35799781 PMCID: PMC9254734 DOI: 10.3389/fimmu.2022.865180] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 05/05/2022] [Indexed: 02/03/2023] Open
Abstract
Dengue virus (DENV) is an arboviral disease affecting more than 400 million people annually. Only a single vaccine formulation is available commercially and many others are still under clinical trials. Despite all the efforts in vaccine designing, the improvement in vaccine formulation against DENV is very much needed. In this study, we used a roboust immunoinformatics approach, targeting all the four serotypes of DENV to design a multi-epitope vaccine. A total of 13501 MHC II binding CD4+ epitope peptides were predicted from polyprotein sequences of four dengue virus serotypes. Among them, ten conserved epitope peptides that were interferon-inducing were selected and found to be conserved among all the four dengue serotypes. The vaccine was formulated using antigenic, non-toxic and conserved multi epitopes discovered in the in-silico study. Further, the molecular docking and molecular dynamics predicted stable interactions between predicted vaccine and immune receptor, TLR-5. Finally, one of the mapped epitope peptides was synthesized for the validation of antigenicity and antibody production ability where the in-vivo tests on rabbit model was conducted. Our in-vivo analysis clearly indicate that the imunogen designed in this study could stimulate the production of antibodies which further suggest that the vaccine designed possesses good immunogenicity.
Collapse
Affiliation(s)
- Vikas Kaushik
- Domain of Bioinformatics, School of Bio-Engineering and Bio-Sciences, Lovely Professional University, Punjab, India
| | - Sunil Krishnan G
- Domain of Bioinformatics, School of Bio-Engineering and Bio-Sciences, Lovely Professional University, Punjab, India
| | - Lovi Raj Gupta
- Domain of Bioinformatics, School of Bio-Engineering and Bio-Sciences, Lovely Professional University, Punjab, India
| | - Utkarsh Kalra
- Department of Research and Innovation, STEMskills Research and Education Lab Private Limited, Faridabad, India
- Department of Data Science, Innopolis University, Innopolis, Russia
| | - Abdul Rajjak Shaikh
- Department of Research and Innovation, STEMskills Research and Education Lab Private Limited, Faridabad, India
- *Correspondence: Abdul Rajjak Shaikh, ; Luigi Cavallo, ; Mohit Chawla, ;
| | - Luigi Cavallo
- Kaust Catalysis Center, Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
- *Correspondence: Abdul Rajjak Shaikh, ; Luigi Cavallo, ; Mohit Chawla, ;
| | - Mohit Chawla
- Kaust Catalysis Center, Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
- *Correspondence: Abdul Rajjak Shaikh, ; Luigi Cavallo, ; Mohit Chawla, ;
| |
Collapse
|
8
|
Yu Y, Si L, Meng Y. Flavivirus Entry Inhibitors. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1366:171-197. [PMID: 35412141 DOI: 10.1007/978-981-16-8702-0_11] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Flaviviruses, including Dengue virus, Zika virus, Yellow fever virus, Japanese encephalitis virus, West Nile virus, cause thousands of deaths and millions of illnesses each year. The large outbreak of ZIKV in 2016 reminds us that flaviviruses can pose a serious threat to human safety and public health as emerging and re-emerging viruses. However, there are no specific drugs approved for the treatment of flavivirus infections. Due to no need to enter the cells, viral entry inhibitors have the unique advantage in suppressing viral infections. Flaviviruses bind to receptors and attach to the cell surface, then enter the endosome in a clathrin-dependent manner and finalizes the viral entry process after fusion with the cell membrane in a low pH environment. Small molecules, antibodies or peptides can inhibit flavivirus entry by targeting the above processes. Here, we focus on flavivirus entry inhibitors with well-defined target and antiviral activity. We hope that our review will provide a theoretical basis for flavivirus treatment and drug research and help to accelerate the clinical application of flavivirus entry inhibitors.
Collapse
Affiliation(s)
- Yufeng Yu
- Medical School, Nanjing University, Nanjing, Jiangsu, China.
| | - Lulu Si
- The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Yu Meng
- Department of Microbiology and Immunology, College of Basic Medical Sciences, Dali University, Dali, Yunnan, China
| |
Collapse
|
9
|
Charged Residue Implantation Improves the Affinity of a Cross-Reactive Dengue Virus Antibody. Int J Mol Sci 2022; 23:ijms23084197. [PMID: 35457015 PMCID: PMC9027083 DOI: 10.3390/ijms23084197] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 04/01/2022] [Accepted: 04/08/2022] [Indexed: 11/23/2022] Open
Abstract
Dengue virus (DENV) has four serotypes that complicate vaccine development. Envelope protein domain III (EDIII) of DENV is a promising target for therapeutic antibody development. One EDIII-specific antibody, dubbed 1A1D-2, cross-reacts with DENV 1, 2, and 3 but not 4. To improve the affinity of 1A1D-2, in this study, we analyzed the previously solved structure of 1A1D-2-DENV2 EDIII complex. Mutations were designed, including A54E and Y105R in the heavy chain, with charges complementary to the epitope. Molecular dynamics simulation was then used to validate the formation of predicted salt bridges. Interestingly, a surface plasmon resonance experiment showed that both mutations increased affinities of 1A1D-2 toward EDIII of DENV1, 2, and 3 regardless of their sequence variation. Results also revealed that A54E improved affinities through both a faster association and slower dissociation, whereas Y105R improved affinities through a slower dissociation. Further simulation suggested that the same mutants interacted with different residues in different serotypes. Remarkably, combination of the two mutations additively improved 1A1D-2 affinity by 8, 36, and 13-fold toward DENV1, 2, and 3, respectively. In summary, this study demonstrated the utility of tweaking antibody-antigen charge complementarity for affinity maturation and emphasized the complexity of improving antibody affinity toward multiple antigens.
Collapse
|
10
|
Anasir MI, Poh CL. Discovery of B-cell epitopes for development of dengue vaccines and antibody therapeutics. Med Microbiol Immunol 2022; 211:1-18. [PMID: 35059822 DOI: 10.1007/s00430-021-00726-1] [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: 07/21/2021] [Accepted: 12/04/2021] [Indexed: 10/19/2022]
Abstract
Dengue is one of the most frequently transmitted viral infections globally which creates a serious burden to the healthcare system in many countries in the tropical and subtropical regions. To date, no vaccine has demonstrated balanced protection against the four dengue serotypes. Dengvaxia as the only vaccine that has been licensed for use in endemic areas has shown an increased risk in dengue-naïve vaccines to develop severe dengue. A crucial element in protection from dengue infection is the neutralizing antibody responses. Therefore, the identification of protective linear B-cell epitopes can guide vaccine design and facilitate the development of monoclonal antibodies as dengue therapeutics. This review summarizes the identification of dengue B-cell epitopes within the envelope (E) protein of dengue that can be incorporated into peptide vaccine constructs. These epitopes have been identified through approaches such as bioinformatics, three-dimensional structure analysis of antibody-dengue complexes, mutagenesis/alanine scanning and escape mutant studies. Additionally, the therapeutic potential of monoclonal antibodies targeting the E protein of dengue is reviewed. This can provide a basis for the design of future dengue therapies.
Collapse
Affiliation(s)
- Mohd Ishtiaq Anasir
- Virology Unit, Infectious Disease Research Centre, Institute for Medical Research, National Institutes of Health, Setia Alam, Shah Alam, Selangor, Malaysia
- Centre for Virus and Vaccine Research, Sunway University, 5, Jalan Universiti, 47500, Bandar Sunway, Selangor, Malaysia
| | - Chit Laa Poh
- Centre for Virus and Vaccine Research, Sunway University, 5, Jalan Universiti, 47500, Bandar Sunway, Selangor, Malaysia.
| |
Collapse
|
11
|
Horst A, Smakaj E, Natali EN, Tosoni D, Babrak LM, Meier P, Miho E. Machine Learning Detects Anti-DENV Signatures in Antibody Repertoire Sequences. Front Artif Intell 2021; 4:715462. [PMID: 34708197 PMCID: PMC8542978 DOI: 10.3389/frai.2021.715462] [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: 05/27/2021] [Accepted: 07/30/2021] [Indexed: 11/13/2022] Open
Abstract
Dengue infection is a global threat. As of today, there is no universal dengue fever treatment or vaccines unreservedly recommended by the World Health Organization. The investigation of the specific immune response to dengue virus would support antibody discovery as therapeutics for passive immunization and vaccine design. High-throughput sequencing enables the identification of the multitude of antibodies elicited in response to dengue infection at the sequence level. Artificial intelligence can mine the complex data generated and has the potential to uncover patterns in entire antibody repertoires and detect signatures distinctive of single virus-binding antibodies. However, these machine learning have not been harnessed to determine the immune response to dengue virus. In order to enable the application of machine learning, we have benchmarked existing methods for encoding biological and chemical knowledge as inputs and have investigated novel encoding techniques. We have applied different machine learning methods such as neural networks, random forests, and support vector machines and have investigated the parameter space to determine best performing algorithms for the detection and prediction of antibody patterns at the repertoire and antibody sequence levels in dengue-infected individuals. Our results show that immune response signatures to dengue are detectable both at the antibody repertoire and at the antibody sequence levels. By combining machine learning with phylogenies and network analysis, we generated novel sequences that present dengue-binding specific signatures. These results might aid further antibody discovery and support vaccine design.
Collapse
Affiliation(s)
- Alexander Horst
- School of Life Sciences, Institute of Medical Engineering and Medical Informatics, University of Applied Sciences and Arts Northwestern Switzerland FHNW, Muttenz, Switzerland
| | - Erand Smakaj
- School of Life Sciences, Institute of Medical Engineering and Medical Informatics, University of Applied Sciences and Arts Northwestern Switzerland FHNW, Muttenz, Switzerland
| | - Eriberto Noel Natali
- School of Life Sciences, Institute of Medical Engineering and Medical Informatics, University of Applied Sciences and Arts Northwestern Switzerland FHNW, Muttenz, Switzerland
| | - Deniz Tosoni
- School of Life Sciences, Institute of Medical Engineering and Medical Informatics, University of Applied Sciences and Arts Northwestern Switzerland FHNW, Muttenz, Switzerland
| | - Lmar Marie Babrak
- School of Life Sciences, Institute of Medical Engineering and Medical Informatics, University of Applied Sciences and Arts Northwestern Switzerland FHNW, Muttenz, Switzerland
| | - Patrick Meier
- School of Life Sciences, Institute of Medical Engineering and Medical Informatics, University of Applied Sciences and Arts Northwestern Switzerland FHNW, Muttenz, Switzerland
| | - Enkelejda Miho
- School of Life Sciences, Institute of Medical Engineering and Medical Informatics, University of Applied Sciences and Arts Northwestern Switzerland FHNW, Muttenz, Switzerland.,SIB Swiss Institute of Bioinformatics, Lausanne, Switzerland.,aiNET GmbH, Basel, Switzerland
| |
Collapse
|
12
|
Fibriansah G, Lim XN, Lok SM. Morphological Diversity and Dynamics of Dengue Virus Affecting Antigenicity. Viruses 2021; 13:v13081446. [PMID: 34452312 PMCID: PMC8402850 DOI: 10.3390/v13081446] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 07/15/2021] [Accepted: 07/21/2021] [Indexed: 01/30/2023] Open
Abstract
The four serotypes of the mature dengue virus can display different morphologies, including the compact spherical, the bumpy spherical and the non-spherical clubshape morphologies. In addition, the maturation process of dengue virus is inefficient and therefore some partially immature dengue virus particles have been observed and they are infectious. All these viral particles have different antigenicity profiles and thus may affect the type of the elicited antibodies during an immune response. Understanding the molecular determinants and environmental conditions (e.g., temperature) in inducing morphological changes in the virus and how potent antibodies interact with these particles is important for designing effective therapeutics or vaccines. Several techniques, including cryoEM, site-directed mutagenesis, hydrogen-deuterium exchange mass spectrometry, time-resolve fluorescence resonance energy transfer, and molecular dynamic simulation, have been performed to investigate the structural changes. This review describes all known morphological variants of DENV discovered thus far, their surface protein dynamics and the key residues or interactions that play important roles in the structural changes.
Collapse
Affiliation(s)
- Guntur Fibriansah
- Programme in Emerging Infectious Diseases, Duke–National University of Singapore Medical School, Singapore 169857, Singapore; (G.F.); (X.-N.L.)
- Centre for BioImaging Sciences, Department of Biological Sciences, National University of Singapore, Singapore 117557, Singapore
| | - Xin-Ni Lim
- Programme in Emerging Infectious Diseases, Duke–National University of Singapore Medical School, Singapore 169857, Singapore; (G.F.); (X.-N.L.)
- Centre for BioImaging Sciences, Department of Biological Sciences, National University of Singapore, Singapore 117557, Singapore
| | - Shee-Mei Lok
- Programme in Emerging Infectious Diseases, Duke–National University of Singapore Medical School, Singapore 169857, Singapore; (G.F.); (X.-N.L.)
- Centre for BioImaging Sciences, Department of Biological Sciences, National University of Singapore, Singapore 117557, Singapore
- Correspondence:
| |
Collapse
|
13
|
Kotaki T, Kurosu T, Grinyo-Escuer A, Davidson E, Churrotin S, Okabayashi T, Puiprom O, Mulyatno KC, Sucipto TH, Doranz BJ, Ono KI, Soegijanto S, Kameoka M. An affinity-matured human monoclonal antibody targeting fusion loop epitope of dengue virus with in vivo therapeutic potency. Sci Rep 2021; 11:12987. [PMID: 34155267 PMCID: PMC8217507 DOI: 10.1038/s41598-021-92403-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 06/08/2021] [Indexed: 11/26/2022] Open
Abstract
Dengue virus (DENV), from the genus flavivirus of the family flaviviridae, causes serious health problems globally. Human monoclonal antibodies (HuMAb) can be used to elucidate the mechanisms of neutralization and antibody-dependent enhancement (ADE) of DENV infections, leading to the development of a vaccine or therapeutic antibodies. Here, we generated eight HuMAb clones from an Indonesian patient infected with DENV. These HuMAbs exhibited the typical characteristics of weak neutralizing antibodies including high cross-reactivity with other flaviviruses and targeting of the fusion loop epitope (FLE). However, one of the HuMAbs, 3G9, exhibited strong neutralization (NT50 < 0.1 μg/ml) and possessed a high somatic hyper-mutation rate of the variable region, indicating affinity-maturation. Administration of this antibody significantly prolonged the survival of interferon-α/β/γ receptor knockout C57BL/6 mice after a lethal DENV challenge. Additionally, Fc-modified 3G9 that had lost their in vitro ADE activity showed enhanced therapeutic potency in vivo and competed strongly with an ADE-prone antibody in vitro. Taken together, the affinity-matured FLE-targeting antibody 3G9 exhibits promising features for therapeutic application including a low NT50 value, potential for treatment of various kinds of mosquito-borne flavivirus infection, and suppression of ADE. This study demonstrates the therapeutic potency of affinity-matured FLE-targeting antibodies.
Collapse
Affiliation(s)
- Tomohiro Kotaki
- Department of Public Health, Kobe University Graduate School of Health Sciences, Kobe, Japan.
- Collaborative Research Center for Emerging and Re-Emerging Infectious Diseases, Institute of Tropical Disease, Airlangga University, Surabaya, Indonesia.
- Department of Virology, Research Institute for Microbial Diseases, Osaka University, Suita, Japan.
| | - Takeshi Kurosu
- Department of Virology I, National Institute of Infectious Diseases (NIID), Tokyo, Japan
| | | | | | - Siti Churrotin
- Collaborative Research Center for Emerging and Re-Emerging Infectious Diseases, Institute of Tropical Disease, Airlangga University, Surabaya, Indonesia
| | - Tamaki Okabayashi
- Mahidol-Osaka Center for Infectious Diseases (MOCID), Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Orapim Puiprom
- Mahidol-Osaka Center for Infectious Diseases (MOCID), Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Kris Cahyo Mulyatno
- Collaborative Research Center for Emerging and Re-Emerging Infectious Diseases, Institute of Tropical Disease, Airlangga University, Surabaya, Indonesia
| | - Teguh Hari Sucipto
- Collaborative Research Center for Emerging and Re-Emerging Infectious Diseases, Institute of Tropical Disease, Airlangga University, Surabaya, Indonesia
| | | | - Ken-Ichiro Ono
- Medical & Biological Laboratories Co., Ltd., Tokyo, Japan
| | - Soegeng Soegijanto
- Collaborative Research Center for Emerging and Re-Emerging Infectious Diseases, Institute of Tropical Disease, Airlangga University, Surabaya, Indonesia
| | - Masanori Kameoka
- Department of Public Health, Kobe University Graduate School of Health Sciences, Kobe, Japan.
| |
Collapse
|
14
|
Hardy JM, Newton ND, Modhiran N, Scott CAP, Venugopal H, Vet LJ, Young PR, Hall RA, Hobson-Peters J, Coulibaly F, Watterson D. A unified route for flavivirus structures uncovers essential pocket factors conserved across pathogenic viruses. Nat Commun 2021; 12:3266. [PMID: 34075032 PMCID: PMC8169900 DOI: 10.1038/s41467-021-22773-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 03/24/2021] [Indexed: 12/27/2022] Open
Abstract
The epidemic emergence of relatively rare and geographically isolated flaviviruses adds to the ongoing disease burden of viruses such as dengue. Structural analysis is key to understand and combat these pathogens. Here, we present a chimeric platform based on an insect-specific flavivirus for the safe and rapid structural analysis of pathogenic viruses. We use this approach to resolve the architecture of two neurotropic viruses and a structure of dengue virus at 2.5 Å, the highest resolution for an enveloped virion. These reconstructions allow improved modelling of the stem region of the envelope protein, revealing two lipid-like ligands within highly conserved pockets. We show that these sites are essential for viral growth and important for viral maturation. These findings define a hallmark of flavivirus virions and a potential target for broad-spectrum antivirals and vaccine design. We anticipate the chimeric platform to be widely applicable for investigating flavivirus biology. Understanding virus assembly could identify potential drug targets. Here the authors use a safe and efficient method to solve pathogenic flavivirus structures, revealing two lipid-like ligands within highly conserved pockets of the stem region of envelope protein that are important for virus maturation.
Collapse
Affiliation(s)
- Joshua M Hardy
- Infection and Immunity Program, Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia
| | - Natalee D Newton
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia
| | - Naphak Modhiran
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia
| | - Connor A P Scott
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia
| | - Hariprasad Venugopal
- Ramaciotti Centre for Cryo-Electron Microscopy, Monash University, Clayton, VIC, Australia
| | - Laura J Vet
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia
| | - Paul R Young
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia
| | - Roy A Hall
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia
| | - Jody Hobson-Peters
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia
| | - Fasséli Coulibaly
- Infection and Immunity Program, Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia.
| | - Daniel Watterson
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia.
| |
Collapse
|
15
|
Rajan JV, McCracken M, Mandel-Brehm C, Gromowski G, Pollett S, Jarman R, DeRisi JL. Phage display demonstrates durable differences in serological profile by route of inoculation in primary infections of non-human primates with Dengue Virus 1. Sci Rep 2021; 11:10823. [PMID: 34031504 PMCID: PMC8144558 DOI: 10.1038/s41598-021-90318-z] [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: 12/23/2020] [Accepted: 04/29/2021] [Indexed: 11/21/2022] Open
Abstract
Natural dengue virus (DENV) infections occur by mosquito bite but how the inoculation route affects the humoral immune response is unknown. We serologically profiled 20 non-human primates (NHP) from a prior study of DENV1 infection where animals were inoculated by mosquito (N = 10) or subcutaneous injection (N = 10). Using a comprehensive, densely tiled and highly redundant pan-flavivirus programmable phage library containing 91,562 overlapping 62 amino acid peptides, we produced a high-resolution map of linear peptide sequences enriched during DENV seroconversion. Profiles in mosquito-inoculated and subcutaneously-inoculated animals were similar up to 90 days after primary infection, but diverged at 1 year with differences in sero-reactivity in the Envelope (E; residues 215–406; p < 0.08), and Nonstructural-3 (NS3; residues 549–615; p < 0.05) proteins in mosquito-inoculated versus subcutaneously-inoculated animals. Within the E protein, residues 339–384 in domain III accounted for > 99% of the observed sero-reactivity difference. Antibody breadth did not vary by mode of inoculation. The differential reactivity to E domain III seen by phage display validated orthogonally by ELISA, but did not correlate with late neutralization titers. Serological profiling of humoral immune responses to DENV infection in NHP by programmable phage display demonstrated durable differences in sero-reactivity by route of inoculation.
Collapse
Affiliation(s)
- Jayant V Rajan
- University of California, San Francisco, San Francisco, CA, USA.
| | | | | | - Greg Gromowski
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Simon Pollett
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Richard Jarman
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Joseph L DeRisi
- University of California, San Francisco, San Francisco, CA, USA.,Chan-Zuckerberg Biohub, San Francisco, CA, USA
| |
Collapse
|
16
|
Tsai WY, Driesse K, Tsai JJ, Hsieh SC, Sznajder Granat R, Jenkins O, Chang GJ, Wang WK. Enzyme-linked immunosorbent assays using virus-like particles containing mutations of conserved residues on envelope protein can distinguish three flavivirus infections. Emerg Microbes Infect 2021; 9:1722-1732. [PMID: 32684139 PMCID: PMC7473235 DOI: 10.1080/22221751.2020.1797540] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The recent outbreaks of Zika virus (ZIKV) in flavivirus-endemic regions highlight the need for sensitive and specific serological tests. Previously we and others reported key fusion loop (FL) residues and/or BC loop (BCL) residues on dengue virus (DENV) envelope protein recognized by flavivirus cross-reactive human monoclonal antibodies and polyclonal sera. To improve ZIKV serodiagnosis, we employed wild type (WT) and FL or FL/BCL mutant virus-like particles (VLP) of ZIKV, DENV1 and West Nile virus (WNV) in enzyme linked immunosorbent assays (ELISA), and tested convalescent-phase serum or plasma samples from reverse-transcription PCR-confirmed cases with different ZIKV, DENV and WNV infections. For IgG ELISA, ZIKV WT-VLP had a sensitivity of 100% and specificity of 52.9%, which was improved to 83.3% by FL/BCL mutant VLP and 92.2% by the ratio of relative optical density of mutant to WT VLP. Similarly, DENV1 and WNV WT-VLP had a sensitivity/specificity of 100%/70.0% and 100%/56.3%, respectively; the specificity was improved to 93.3% and 83.0% by FL mutant VLP. For IgM ELISA, ZIKV, DENV1 and WNV WT-VLP had a specificity of 96.4%, 92.3% and 91.4%, respectively, for primary infection; the specificity was improved to 93.7–99.3% by FL or FL/BCL mutant VLP. An algorithm based on a combination of mutant and WT-VLP IgG ELISA is proposed to discriminate primary ZIKV, DENV and WNV infections as well as secondary DENV and ZIKV infection with previous DENV infections; this could be a powerful tool to better understand the seroprevalence and pathogenesis of ZIKV in regions where multiple flaviviruses co-circulate.
Collapse
Affiliation(s)
- Wen-Yang Tsai
- Department of Tropical Medicine, Medical Microbiology and Pharmacology, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI, USA
| | - Kaitlin Driesse
- Department of Tropical Medicine, Medical Microbiology and Pharmacology, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI, USA
| | - Jih-Jin Tsai
- Tropical Medicine Center, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.,Division of Infectious Diseases, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.,School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Szu-Chia Hsieh
- Department of Tropical Medicine, Medical Microbiology and Pharmacology, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI, USA
| | | | - Olivia Jenkins
- Department of Tropical Medicine, Medical Microbiology and Pharmacology, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI, USA
| | - Gwong-Jen Chang
- Division of Vector-Borne Diseases, Center for Disease Control and Prevention, US Department of Health and Human Service, Fort Collins, CO, USA
| | - Wei-Kung Wang
- Department of Tropical Medicine, Medical Microbiology and Pharmacology, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI, USA
| |
Collapse
|
17
|
Fibriansah G, Lim EXY, Marzinek JK, Ng TS, Tan JL, Huber RG, Lim XN, Chew VSY, Kostyuchenko VA, Shi J, Anand GS, Bond PJ, Crowe JE, Lok SM. Antibody affinity versus dengue morphology influences neutralization. PLoS Pathog 2021; 17:e1009331. [PMID: 33621239 PMCID: PMC7935256 DOI: 10.1371/journal.ppat.1009331] [Citation(s) in RCA: 6] [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: 10/09/2020] [Revised: 03/05/2021] [Accepted: 01/25/2021] [Indexed: 12/23/2022] Open
Abstract
Different strains within a dengue serotype (DENV1-4) can have smooth, or “bumpy” surface morphologies with different antigenic characteristics at average body temperature (37°C). We determined the neutralizing properties of a serotype cross-reactive human monoclonal antibody (HMAb) 1C19 for strains with differing morphologies within the DENV1 and DENV2 serotypes. We mapped the 1C19 epitope to E protein domain II by hydrogen deuterium exchange mass spectrometry, cryoEM and molecular dynamics simulations, revealing that this epitope is likely partially hidden on the virus surface. We showed the antibody has high affinity for binding to recombinant DENV1 E proteins compared to those of DENV2, consistent with its strong neutralizing activities for all DENV1 strains tested regardless of their morphologies. This finding suggests that the antibody could out-compete E-to-E interaction for binding to its epitope. In contrast, for DENV2, HMAb 1C19 can only neutralize when the epitope becomes exposed on the bumpy-surfaced particle. Although HMAb 1C19 is not a suitable therapeutic candidate, this study with HMAb 1C19 shows the importance of choosing a high-affinity antibody that could neutralize diverse dengue virus morphologies for therapeutic purposes. Dengue virus consists of four serotypes (DENV1-4) and there are different strains within a serotype. DENV can have smooth or bumpy surface morphologies at physiological body temperature of 37°C, depending on the strain. We have determined the cryoEM structures of a cross-reactive neutralizing human monoclonal antibody (HMAb) 1C19 in complex with strains of DENV1 and DENV2 that form either smooth or bumpy surface morphologies. We have mapped the epitope of HMAb 1C19 to E protein domain II and the epitope is likely partially hidden on the virus surface. We showed that the antibody has high affinity for binding to recombinant DENV1 E protein than to DENV2 E protein. This explains the strong neutralization activity for all DENV1 strains tested regardless of their morphologies at physiological temperature, whereas it can only neutralize DENV2 strain that exposes the epitope on the bumpy surface particles. These results suggest that high-affinity therapeutic antibodies could neutralize diverse dengue virus morphologies.
Collapse
Affiliation(s)
- Guntur Fibriansah
- Emerging Infectious Diseases, Duke–National University of Singapore Medical School, Singapore, Singapore
- Centre for BioImaging Sciences, National University of Singapore, Singapore, Singapore
| | - Elisa X. Y. Lim
- Emerging Infectious Diseases, Duke–National University of Singapore Medical School, Singapore, Singapore
- Centre for BioImaging Sciences, National University of Singapore, Singapore, Singapore
| | - Jan K. Marzinek
- Bioinformatics Institute, A*STAR (Agency for Science, Technology and Research), Singapore, Singapore
| | - Thiam-Seng Ng
- Emerging Infectious Diseases, Duke–National University of Singapore Medical School, Singapore, Singapore
- Centre for BioImaging Sciences, National University of Singapore, Singapore, Singapore
| | - Joanne L. Tan
- Emerging Infectious Diseases, Duke–National University of Singapore Medical School, Singapore, Singapore
- Centre for BioImaging Sciences, National University of Singapore, Singapore, Singapore
| | - Roland G. Huber
- Bioinformatics Institute, A*STAR (Agency for Science, Technology and Research), Singapore, Singapore
| | - Xin-Ni Lim
- Emerging Infectious Diseases, Duke–National University of Singapore Medical School, Singapore, Singapore
- Centre for BioImaging Sciences, National University of Singapore, Singapore, Singapore
| | - Valerie S. Y. Chew
- Emerging Infectious Diseases, Duke–National University of Singapore Medical School, Singapore, Singapore
- Centre for BioImaging Sciences, National University of Singapore, Singapore, Singapore
| | - Victor A. Kostyuchenko
- Emerging Infectious Diseases, Duke–National University of Singapore Medical School, Singapore, Singapore
- Centre for BioImaging Sciences, National University of Singapore, Singapore, Singapore
| | - Jian Shi
- Centre for BioImaging Sciences, National University of Singapore, Singapore, Singapore
| | - Ganesh S. Anand
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Peter J. Bond
- Bioinformatics Institute, A*STAR (Agency for Science, Technology and Research), Singapore, Singapore
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - James E. Crowe
- The Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- Departments of Pediatrics and Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- * E-mail: (JEC); (SML)
| | - Shee-Mei Lok
- Emerging Infectious Diseases, Duke–National University of Singapore Medical School, Singapore, Singapore
- Centre for BioImaging Sciences, National University of Singapore, Singapore, Singapore
- * E-mail: (JEC); (SML)
| |
Collapse
|
18
|
Tsuji I, Dominguez D, Egan MA, Dean HJ. Development of a novel assay to assess the avidity of dengue virus-specific antibodies elicited in response to a tetravalent dengue vaccine. J Infect Dis 2021; 225:1533-1544. [PMID: 33534885 PMCID: PMC9071338 DOI: 10.1093/infdis/jiab064] [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: 10/02/2020] [Accepted: 01/29/2021] [Indexed: 11/28/2022] Open
Abstract
Antibody affinity maturation is a critical step in development of functional antiviral immunity; however, accurate measurement of affinity maturation of polyclonal serum antibody responses to particulate antigens such as virions is challenging. We describe a novel avidity assay employing biolayer interferometry and dengue virus-like particles. After validation using anti-dengue monoclonal antibodies, the assay was used to assess avidity of antibody responses to a tetravalent dengue vaccine candidate (TAK-003) in children, adolescents, and adults during two phase 2 clinical trials conducted in dengue-endemic regions. Vaccination increased avidity index and avidity remained high through 1 year postvaccination. Neutralizing antibody titers and avidity index did not correlate overall; however, a correlation was observed between neutralizing antibody titer and avidity index in those subjects with the highest degree of antibody affinity maturation. Therefore, vaccination with TAK-003 stimulates polyclonal affinity maturation and functional antibody responses, including neutralizing antibodies.
Collapse
|
19
|
Young E, Carnahan RH, Andrade DV, Kose N, Nargi RS, Fritch EJ, Munt JE, Doyle MP, White L, Baric TJ, Stoops M, DeSilva A, Tse LV, Martinez DR, Zhu D, Metz S, Wong MP, Espinosa DA, Montoya M, Biering SB, Sukulpolvi-Petty S, Kuan G, Balmaseda A, Diamond MS, Harris E, Crowe JE, Baric RS. Identification of Dengue Virus Serotype 3 Specific Antigenic Sites Targeted by Neutralizing Human Antibodies. Cell Host Microbe 2021; 27:710-724.e7. [PMID: 32407709 PMCID: PMC7309352 DOI: 10.1016/j.chom.2020.04.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 02/18/2020] [Accepted: 04/06/2020] [Indexed: 12/31/2022]
Abstract
The rational design of dengue virus (DENV) vaccines requires a detailed understanding of the molecular basis for antibody-mediated immunity. The durably protective antibody response to DENV after primary infection is serotype specific. However, there is an incomplete understanding of the antigenic determinants for DENV type-specific (TS) antibodies, especially for DENV serotype 3, which has only one well-studied, strongly neutralizing human monoclonal antibody (mAb). Here, we investigated the human B cell response in children after natural DENV infection in the endemic area of Nicaragua and isolated 15 DENV3 TS mAbs recognizing the envelope (E) glycoprotein. Functional epitope mapping of these mAbs and small animal prophylaxis studies revealed a complex landscape with protective epitopes clustering in at least 6-7 antigenic sites. Potently neutralizing TS mAbs recognized sites principally in E glycoprotein domains I and II, and patterns suggest frequent recognition of quaternary structures on the surface of viral particles.
Collapse
Affiliation(s)
- Ellen Young
- Department of Epidemiology, Gillings School of Public Health, University of North Carolina, Chapel Hill, NC, USA
| | - Robert H Carnahan
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Daniela V Andrade
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California Berkeley, Berkeley, CA, USA
| | - Nurgun Kose
- Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Rachel S Nargi
- Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Ethan J Fritch
- Department of Microbiology and Immunology, School of Medicine, University of North Carolina, Chapel Hill, NC, USA
| | - Jennifer E Munt
- Department of Epidemiology, Gillings School of Public Health, University of North Carolina, Chapel Hill, NC, USA
| | - Michael P Doyle
- Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Laura White
- Department of Microbiology and Immunology, School of Medicine, University of North Carolina, Chapel Hill, NC, USA
| | - Thomas J Baric
- Department of Epidemiology, Gillings School of Public Health, University of North Carolina, Chapel Hill, NC, USA
| | - Mark Stoops
- Department of Microbiology and Immunology, School of Medicine, University of North Carolina, Chapel Hill, NC, USA
| | - Aravinda DeSilva
- Department of Microbiology and Immunology, School of Medicine, University of North Carolina, Chapel Hill, NC, USA
| | - Longping V Tse
- Department of Epidemiology, Gillings School of Public Health, University of North Carolina, Chapel Hill, NC, USA
| | - David R Martinez
- Department of Epidemiology, Gillings School of Public Health, University of North Carolina, Chapel Hill, NC, USA
| | - Deanna Zhu
- Department of Epidemiology, Gillings School of Public Health, University of North Carolina, Chapel Hill, NC, USA
| | - Stefan Metz
- Department of Microbiology and Immunology, School of Medicine, University of North Carolina, Chapel Hill, NC, USA
| | - Marcus P Wong
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California Berkeley, Berkeley, CA, USA
| | - Diego A Espinosa
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California Berkeley, Berkeley, CA, USA
| | - Magelda Montoya
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California Berkeley, Berkeley, CA, USA
| | - Scott B Biering
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California Berkeley, Berkeley, CA, USA
| | - Soila Sukulpolvi-Petty
- Department of Medicine, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Guillermina Kuan
- Health Center Sócrates Flores Vivas, Ministry of Health, Managua, Nicaragua
| | - Angel Balmaseda
- National Virology Laboratory, National Center for Diagnosis and Reference, Ministry of Health, Managua, Nicaragua
| | - Michael S Diamond
- Department of Medicine, Washington University School of Medicine, Saint Louis, MO 63110, USA; Molecular Microbiology, Washington University School of Medicine, Saint Louis, MO 63110, USA; Pathology & Immunology, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Eva Harris
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California Berkeley, Berkeley, CA, USA.
| | - James E Crowe
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA; Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA.
| | - Ralph S Baric
- Department of Epidemiology, Gillings School of Public Health, University of North Carolina, Chapel Hill, NC, USA; Department of Microbiology and Immunology, School of Medicine, University of North Carolina, Chapel Hill, NC, USA.
| |
Collapse
|
20
|
A potent neutralizing mouse monoclonal antibody specific to dengue virus type 1 Mochizuki strain recognized a novel epitope around the N-67 glycan on the envelope protein: A possible explanation of dengue virus evolution regarding the acquisition of N-67 glycan. Virus Res 2020; 294:198278. [PMID: 33388392 DOI: 10.1016/j.virusres.2020.198278] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 12/20/2020] [Accepted: 12/21/2020] [Indexed: 12/15/2022]
Abstract
The analysis of neutralizing epitope of dengue virus (DENV) is important for the development of an effective dengue vaccine. A potent neutralizing mouse monoclonal antibody named 7F4 was previously reported and, here, we further analyzed the detailed epitope of this antibody. 7F4 recognized a novel conformational epitope close to the N-67 glycan on the envelope protein. This antibody was specific to the DENV that lacks N-67 glycan, including the Mochizuki strain. Interestingly, the Mochizuki strain acquired N-67 glycan by 7F4 selective pressure. Considering that most of the currently circulating DENVs possess N-67 glycan, DENVs may have evolved to escape from antibodies targeting 7F4 epitope, suggesting the potency of this neutralizing epitope. In addition, this study demonstrated the existence of the epitopes close to 7F4 epitope and their crucial role in neutralization. In conclusion, the epitopes close to the N-67 glycan are attractive targets for the dengue vaccine antigen. Further analysis of this epitope is warranted.
Collapse
|
21
|
Subdominance in Antibody Responses: Implications for Vaccine Development. Microbiol Mol Biol Rev 2020; 85:85/1/e00078-20. [PMID: 33239435 DOI: 10.1128/mmbr.00078-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Vaccines work primarily by eliciting antibodies, even when recovery from natural infection depends on cellular immunity. Large efforts have therefore been made to identify microbial antigens that elicit protective antibodies, but these endeavors have encountered major difficulties, as witnessed by the lack of vaccines against many pathogens. This review summarizes accumulating evidence that subdominant protein regions, i.e., surface-exposed regions that elicit relatively weak antibody responses, are of particular interest for vaccine development. This concept may seem counterintuitive, but subdominance may represent an immune evasion mechanism, implying that the corresponding region potentially is a key target for protective immunity. Following a presentation of the concepts of immunodominance and subdominance, the review will present work on subdominant regions in several major human pathogens: the protozoan Plasmodium falciparum, two species of pathogenic streptococci, and the dengue and influenza viruses. Later sections are devoted to the molecular basis of subdominance, its potential role in immune evasion, and general implications for vaccine development. Special emphasis will be placed on the fact that a whole surface-exposed protein domain can be subdominant, as demonstrated for all of the pathogens described here. Overall, the available data indicate that subdominant protein regions are of much interest for vaccine development, not least in bacterial and protozoal systems, for which antibody subdominance remains largely unexplored.
Collapse
|
22
|
Shukla R, Ramasamy V, Shanmugam RK, Ahuja R, Khanna N. Antibody-Dependent Enhancement: A Challenge for Developing a Safe Dengue Vaccine. Front Cell Infect Microbiol 2020; 10:572681. [PMID: 33194810 PMCID: PMC7642463 DOI: 10.3389/fcimb.2020.572681] [Citation(s) in RCA: 83] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 09/15/2020] [Indexed: 01/05/2023] Open
Abstract
In 2019, the United States Food and Drug Administration accorded restricted approval to Sanofi Pasteur's Dengvaxia, a live attenuated vaccine (LAV) for dengue fever, a mosquito-borne viral disease, caused by four antigenically distinct dengue virus serotypes (DENV 1-4). The reason for this limited approval is the concern that this vaccine sensitized some of the dengue-naïve recipients to severe dengue fever. Recent knowledge about the nature of the immune response elicited by DENV viruses suggests that all LAVs have inherent capacity to predominantly elicit antibodies (Abs) against the pre-membrane (prM) and fusion loop epitope (FLE) of DENV. These antibodies are generally cross-reactive among DENV serotypes carrying a higher risk of promoting Antibody-Dependent Enhancement (ADE). ADE is a phenomenon in which suboptimal neutralizing or non-neutralizing cross-reactive antibodies bind to virus and facilitate Fcγ receptor mediated enhanced entry into host cells, followed by its replication, and thus increasing the cellular viral load. On the other hand, antibody responses directed against the host-cell receptor binding domain of DENV envelope domain-III (EDIII), exhibit a higher degree of type-specificity with lower potential of ADE. The challenges associated with whole DENV-based vaccine strategies necessitate re-focusing our attention toward the designed dengue vaccine candidates, capable of inducing predominantly type-specific immune responses. If the designed vaccines elicited predominantly EDIII-directed serotype specific antibodies in the absence of prM and FLE antibodies, this could avoid the ADE phenomenon largely associated with the prM and FLE antibodies. The generation of type-specific antibodies to each of the four DENV serotypes by the designed vaccines could avoid the immune evasion mechanisms of DENVs. For the enhanced vaccine safety, all dengue vaccine candidates should be assessed for the extent of type-specific (minimal ADE) vs. cross-reactive (ADE promoting) neutralizing antibodies. The type-specific EDIII antibodies may be more directly related to protection from disease in the absence of ADE promoted by the cross-reactive antibodies.
Collapse
Affiliation(s)
- Rahul Shukla
- Translational Health Group, Molecular Medicine Division, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Viswanathan Ramasamy
- Translational Health Group, Molecular Medicine Division, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Rajgokul K Shanmugam
- Translational Health Group, Molecular Medicine Division, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Richa Ahuja
- Translational Health Group, Molecular Medicine Division, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Navin Khanna
- Translational Health Group, Molecular Medicine Division, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| |
Collapse
|
23
|
Mapping the diverse structural landscape of the flavivirus antibody repertoire. Curr Opin Virol 2020; 45:51-64. [PMID: 32801077 DOI: 10.1016/j.coviro.2020.07.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 07/01/2020] [Accepted: 07/07/2020] [Indexed: 02/08/2023]
Abstract
Flaviviruses are emerging arthropod-borne RNA viruses, causing a broad spectrum of life-threatening disease symptoms such as encephalitis and hemorrhagic fever. Successful vaccines exist against yellow fever virus, Japanese encephalitis virus and tick-borne encephalitis virus. However, vaccine development against other flaviviruses like dengue virus is not straightforward. This is partly because of the high sequence conservation and immunological cross-reactivity among flavivirus envelope glycoproteins leading to antibody mediated enhancement of disease. A comprehensive analyses of the structural landscape of humoral immune response against flaviviruses is crucial for antigen design. Here, we compare the available structural data of several flavivirus antibody complexes with a major focus on Zika virus and dengue virus and discuss the mapped epitopes, the stoichiometry of antibody binding and mechanisms of neutralization.
Collapse
|
24
|
Pecetta S, Finco O, Seubert A. Quantum leap of monoclonal antibody (mAb) discovery and development in the COVID-19 era. Semin Immunol 2020; 50:101427. [PMID: 33277154 PMCID: PMC7670927 DOI: 10.1016/j.smim.2020.101427] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 10/16/2020] [Accepted: 11/16/2020] [Indexed: 01/08/2023]
Abstract
In recent years the global market for monoclonal antibodies (mAbs) became a multi-billion-dollar business. This success is mainly driven by treatments in the oncology and autoimmune space. Instead, development of effective mAbs against infectious diseases has been lagging behind. For years the high production cost and limited efficacy have blocked broader application of mAbs in the infectious disease space, which instead has been dominated for almost a century by effective and cheap antibiotics and vaccines. Only very few mAbs against RSV, anthrax, Clostridium difficile or rabies have reached the market. This is about to change. The development of urgently needed and highly effective mAbs as preventive and therapeutic treatments against a variety of pathogens is gaining traction. Vast advances in mAb isolation, engineering and production have entirely shifted the cost-efficacy balance. MAbs against devastating diseases like Ebola, HIV and other complex pathogens are now within reach. This trend is further accelerated by ongoing or imminent health crises like COVID-19 and antimicrobial resistance (AMR), where antibodies could be the last resort. In this review we will retrace the history of antibodies from the times of serum therapy to modern mAbs and lay out how the current run for effective treatments against COVID-19 will lead to a quantum leap in scientific, technological and health care system innovation around mAb treatments for infectious diseases.
Collapse
|
25
|
Tyagi A, Ahmed T, Shi J, Bhushan S. A complex between the Zika virion and the Fab of a broadly cross-reactive neutralizing monoclonal antibody revealed by cryo-EM and single particle analysis at 4.1 Å resolution. JOURNAL OF STRUCTURAL BIOLOGY-X 2020; 4:100028. [PMID: 32647830 PMCID: PMC7337043 DOI: 10.1016/j.yjsbx.2020.100028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 06/10/2020] [Accepted: 06/11/2020] [Indexed: 11/30/2022]
Abstract
Zika virus (ZIKV) recently emerged as a major public health concern because it can cause fetal microcephaly and neurological disease such as the Guillain-Barré syndrome. A particularly potent class of broadly neutralizing antibodies (nAbs) targets a quaternary epitope located at the interface of two envelope proteins monomers, exposed at the surface of the mature virion. This “E-dimer-dependent epitope” (EDE), comprises the fusion loop of one monomer at the tip of domain II of E and a portion of the domains I and III of the adjacent monomer. Since this epitope largely overlaps with the binding site of the precursor membrane protein (prM) during Zika virion maturation, its molecular surface is evolutionary conserved in flaviviruses such as Dengue and Zika viruses, and can elicit antibodies that broadly neutralize various ZIKV strains. Here, we present a cryo-EM reconstruction at 4.1 Å resolution of the virion bound to the antigen binding fragment (Fab) of an antibody that targets this mutationally-constrained quaternary epitope. The Fab incompletely covers the surface of the virion as it does not bind next to its 5-fold icosahedral axes. The structure reveals details of the binding mode of this potent neutralizing class of antibodies and can inform the design of immunogens and vaccines targeting this conserved epitope.
Collapse
Affiliation(s)
- Anu Tyagi
- School of Biological Sciences, Nanyang Technological University, Singapore
| | - Tofayel Ahmed
- School of Biological Sciences, Nanyang Technological University, Singapore
| | - Jian Shi
- Center for Bio-Imaging Sciences, National University of Singapore, Singapore
| | - Shashi Bhushan
- School of Biological Sciences, Nanyang Technological University, Singapore
- Nanyang Institute of Structural Biology, Experimental Medicine Building, 59 Nanyang Drive, 636921, Singapore
- Corresponding author at: School of Biological Sciences, Nanyang Technological University, Singapore.
| |
Collapse
|
26
|
Wilken L, Rimmelzwaan GF. Adaptive Immunity to Dengue Virus: Slippery Slope or Solid Ground for Rational Vaccine Design? Pathogens 2020; 9:pathogens9060470. [PMID: 32549226 PMCID: PMC7350362 DOI: 10.3390/pathogens9060470] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 06/11/2020] [Accepted: 06/12/2020] [Indexed: 12/15/2022] Open
Abstract
The four serotypes of dengue virus are the most widespread causes of arboviral disease, currently placing half of the human population at risk of infection. Pre-existing immunity to one dengue virus serotype can predispose to severe disease following secondary infection with a different serotype. The phenomenon of immune enhancement has complicated vaccine development and likely explains the poor long-term safety profile of a recently licenced dengue vaccine. Therefore, alternative vaccine strategies should be considered. This review summarises studies dissecting the adaptive immune responses to dengue virus infection and (experimental) vaccination. In particular, we discuss the roles of (i) neutralising antibodies, (ii) antibodies to non-structural protein 1, and (iii) T cells in protection and pathogenesis. We also address how these findings could translate into next-generation vaccine approaches that mitigate the risk of enhanced dengue disease. Finally, we argue that the development of a safe and efficacious dengue vaccine is an attainable goal.
Collapse
|
27
|
Wang L, Wang R, Wang L, Ben H, Yu L, Gao F, Shi X, Yin C, Zhang F, Xiang Y, Zhang L. Structural Basis for Neutralization and Protection by a Zika Virus-Specific Human Antibody. Cell Rep 2020; 26:3360-3368.e5. [PMID: 30893607 DOI: 10.1016/j.celrep.2019.02.062] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Revised: 11/22/2018] [Accepted: 02/13/2019] [Indexed: 12/26/2022] Open
Abstract
We previously reported a human monoclonal antibody, ZK2B10, capable of protection against Zika virus (ZIKV) infection and microcephaly in developing mouse embryos. Here, we report the structural features and mechanism of action of ZK2B10. The crystal structure at a resolution of 2.32 Å revealed that the epitope is located on the lateral ridge of DIII of the envelope glycoprotein. Cryo-EM structure with mature ZIKV showed that the antibody binds to DIIIs around the icosahedral 2-fold, 3-fold, and 5-fold axes, a distinct feature compared to those reported for DIII-specific antibodies. The binding of ZK2B10 to ZIKV has no detectable effect on viral attachment to target cells or on conformational changes of the E glycoprotein in the acidic environment, suggesting that ZK2B10 functions at steps between the formation of the fusion intermediate and membrane fusion. These results provide structural and mechanistic insights into how ZK2B10 mediates protection against ZIKV infection.
Collapse
Affiliation(s)
- Lin Wang
- Beijing Advanced Innovation Center for Structural Biology, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Center for Global Health and Infectious Diseases, Department of Basic Medical Sciences, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Ruoke Wang
- Comprehensive AIDS Research Center, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Beijing Advanced Innovation Center for Structural Biology, Center for Global Health and Infectious Diseases, Department of Basic Medical Sciences, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Lei Wang
- Beijing Advanced Innovation Center for Structural Biology, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Center for Global Health and Infectious Diseases, Department of Basic Medical Sciences, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Haijing Ben
- Comprehensive AIDS Research Center, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Beijing Advanced Innovation Center for Structural Biology, Center for Global Health and Infectious Diseases, Department of Basic Medical Sciences, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Lei Yu
- Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou 510060, China
| | - Fei Gao
- Comprehensive AIDS Research Center, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Beijing Advanced Innovation Center for Structural Biology, Center for Global Health and Infectious Diseases, Department of Basic Medical Sciences, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Xuanling Shi
- Comprehensive AIDS Research Center, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Beijing Advanced Innovation Center for Structural Biology, Center for Global Health and Infectious Diseases, Department of Basic Medical Sciences, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Chibiao Yin
- Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou 510060, China
| | - Fuchun Zhang
- Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou 510060, China
| | - Ye Xiang
- Beijing Advanced Innovation Center for Structural Biology, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Center for Global Health and Infectious Diseases, Department of Basic Medical Sciences, School of Medicine, Tsinghua University, Beijing 100084, China.
| | - Linqi Zhang
- Comprehensive AIDS Research Center, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Beijing Advanced Innovation Center for Structural Biology, Center for Global Health and Infectious Diseases, Department of Basic Medical Sciences, School of Medicine, Tsinghua University, Beijing 100084, China.
| |
Collapse
|
28
|
Abdulla A, Wang B, Qian F, Kee T, Blasiak A, Ong YH, Hooi L, Parekh F, Soriano R, Olinger GG, Keppo J, Hardesty CL, Chow EK, Ho D, Ding X. Project IDentif.AI: Harnessing Artificial Intelligence to Rapidly Optimize Combination Therapy Development for Infectious Disease Intervention. ADVANCED THERAPEUTICS 2020; 3:2000034. [PMID: 32838027 PMCID: PMC7235487 DOI: 10.1002/adtp.202000034] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Indexed: 12/24/2022]
Abstract
In 2019/2020, the emergence of coronavirus disease 2019 (COVID‐19) resulted in rapid increases in infection rates as well as patient mortality. Treatment options addressing COVID‐19 included drug repurposing, investigational therapies such as remdesivir, and vaccine development. Combination therapy based on drug repurposing is among the most widely pursued of these efforts. Multi‐drug regimens are traditionally designed by selecting drugs based on their mechanism of action. This is followed by dose‐finding to achieve drug synergy. This approach is widely‐used for drug development and repurposing. Realizing synergistic combinations, however, is a substantially different outcome compared to globally optimizing combination therapy, which realizes the best possible treatment outcome by a set of candidate therapies and doses toward a disease indication. To address this challenge, the results of Project IDentif.AI (Identifying Infectious Disease Combination Therapy with Artificial Intelligence) are reported. An AI‐based platform is used to interrogate a massive 12 drug/dose parameter space, rapidly identifying actionable combination therapies that optimally inhibit A549 lung cell infection by vesicular stomatitis virus within three days of project start. Importantly, a sevenfold difference in efficacy is observed between the top‐ranked combination being optimally and sub‐optimally dosed, demonstrating the critical importance of ideal drug and dose identification. This platform is disease indication and disease mechanism‐agnostic, and potentially applicable to the systematic N‐of‐1 and population‐wide design of highly efficacious and tolerable clinical regimens. This work also discusses key factors ranging from healthcare economics to global health policy that may serve to drive the broader deployment of this platform to address COVID‐19 and future pandemics.
Collapse
Affiliation(s)
- Aynur Abdulla
- Institute for Personalized Medicine School of Biomedical Engineering Shanghai Jiao Tong University Shanghai 200030 China
| | - Boqian Wang
- Institute for Personalized Medicine School of Biomedical Engineering Shanghai Jiao Tong University Shanghai 200030 China
| | - Feng Qian
- Ministry of Education Key Laboratory of Contemporary Anthropology Human Phenome Institute School of Life Sciences Fudan University Shanghai 200438 China
| | - Theodore Kee
- The N.1 Institute for Health (N.1) National University of Singapore Singapore 117456 Singapore.,The Institute for Digital Medicine (WisDM) Yong Loo Lin School of Medicine National University of Singapore Singapore 11756 Singapore.,Department of Biomedical Engineering NUS Engineering National University of Singapore Singapore 117583 Singapore
| | - Agata Blasiak
- The N.1 Institute for Health (N.1) National University of Singapore Singapore 117456 Singapore.,The Institute for Digital Medicine (WisDM) Yong Loo Lin School of Medicine National University of Singapore Singapore 11756 Singapore.,Department of Biomedical Engineering NUS Engineering National University of Singapore Singapore 117583 Singapore
| | - Yoong Hun Ong
- The N.1 Institute for Health (N.1) National University of Singapore Singapore 117456 Singapore
| | - Lissa Hooi
- Cancer Science Institute of Singapore National University of Singapore Singapore 117599 Singapore
| | | | | | - Gene G Olinger
- Global Health Surveillance and Diagnostic Division MRIGlobal Gaithersburg MD 20878 USA.,Boston University School of Medicine Division of Infectious Diseases Boston MA 02118 USA
| | - Jussi Keppo
- NUS Business School and Institute of Operations Research and Analytics National University of Singapore Singapore 119245 Singapore
| | - Chris L Hardesty
- KPMG Global Health and Life Sciences Centre of Excellence Singapore 048581 Singapore
| | - Edward K Chow
- The N.1 Institute for Health (N.1) National University of Singapore Singapore 117456 Singapore.,Cancer Science Institute of Singapore National University of Singapore Singapore 117599 Singapore.,Department of Pharmacology Yong Loo Lin School of Medicine National University of Singapore Singapore 117600 Singapore
| | - Dean Ho
- The N.1 Institute for Health (N.1) National University of Singapore Singapore 117456 Singapore.,The Institute for Digital Medicine (WisDM) Yong Loo Lin School of Medicine National University of Singapore Singapore 11756 Singapore.,Department of Biomedical Engineering NUS Engineering National University of Singapore Singapore 117583 Singapore.,Department of Pharmacology Yong Loo Lin School of Medicine National University of Singapore Singapore 117600 Singapore
| | - Xianting Ding
- Institute for Personalized Medicine School of Biomedical Engineering Shanghai Jiao Tong University Shanghai 200030 China
| |
Collapse
|
29
|
Swanstrom JA, Nivarthi UK, Patel B, Delacruz MJ, Yount B, Widman DG, Durbin AP, Whitehead SS, De Silva AM, Baric RS. Beyond Neutralizing Antibody Levels: The Epitope Specificity of Antibodies Induced by National Institutes of Health Monovalent Dengue Virus Vaccines. J Infect Dis 2020; 220:219-227. [PMID: 30895307 PMCID: PMC6581895 DOI: 10.1093/infdis/jiz109] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 03/19/2019] [Indexed: 11/24/2022] Open
Abstract
Background Dengue virus is an emerging mosquito-borne flavivirus responsible for considerable morbidity and mortality worldwide. The Division of Intramural Research, National Institute of Allergy and Infectious Diseases of the US National Institutes of Health (NIH) has developed live attenuated vaccines to each of the 4 serotypes of dengue virus (DENV1–4). While overall levels of DENV neutralizing antibodies (nAbs) in humans have been correlated with protection, these correlations vary depending on DENV serotype, prevaccination immunostatus, age, and study site. By combining both the level and molecular specificity of nAbs to each serotype, it may be possible to develop more robust correlates that predict long-term outcome. Methods Using depletions and recombinant chimeric epitope transplant DENVs, we evaluate the molecular specificity and mapped specific epitopes and antigenic regions targeted by vaccine-induced nAbs in volunteers who received the NIH monovalent vaccines against each DENV serotype. Results After monovalent vaccination, subjects developed high levels of nAbs that mainly targeted epitopes that are unique (type-specific) to each DENV serotype. The DENV1, 2, and 4 monovalent vaccines induced type-specific nAbs directed to quaternary structure envelope epitopes known to be targets of strongly neutralizing antibodies induced by wild-type DENV infections. Conclusions Our results reported here on the molecular specificity of NIH vaccine–induced antibodies enable new strategies, beyond the absolute levels of nAbs, for determining correlates and mechanisms of protective immunity.
Collapse
Affiliation(s)
- Jesica A Swanstrom
- Department of Epidemiology, Gillings School of Public Health, University of North Carolina at Chapel Hill
| | - Usha K Nivarthi
- Department of Microbiology and Immunology, School of Medicine, University of North Carolina at Chapel Hill
| | - Bhumi Patel
- Department of Microbiology and Immunology, School of Medicine, University of North Carolina at Chapel Hill
| | - Matthew J Delacruz
- Department of Microbiology and Immunology, School of Medicine, University of North Carolina at Chapel Hill
| | - Boyd Yount
- Department of Epidemiology, Gillings School of Public Health, University of North Carolina at Chapel Hill
| | - Douglas G Widman
- Department of Epidemiology, Gillings School of Public Health, University of North Carolina at Chapel Hill
| | - Anna P Durbin
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore.,Center for Immunization Research, Johns Hopkins Bloomberg School of Public Health, Baltimore
| | - Stephen S Whitehead
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland
| | - Aravinda M De Silva
- Department of Microbiology and Immunology, School of Medicine, University of North Carolina at Chapel Hill
| | - Ralph S Baric
- Department of Epidemiology, Gillings School of Public Health, University of North Carolina at Chapel Hill
| |
Collapse
|
30
|
Li N, Li Z, Fu Y, Cao S. Cryo-EM Studies of Virus-Antibody Immune Complexes. Virol Sin 2020; 35:1-13. [PMID: 31916022 PMCID: PMC7035235 DOI: 10.1007/s12250-019-00190-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Accepted: 11/25/2019] [Indexed: 01/25/2023] Open
Abstract
Antibodies play critical roles in neutralizing viral infections and are increasingly used as therapeutic drugs and diagnostic tools. Structural studies on virus-antibody immune complexes are important for better understanding the molecular mechanisms of antibody-mediated neutralization and also provide valuable information for structure-based vaccine design. Cryo-electron microscopy (cryo-EM) has recently matured as a powerful structural technique for studying bio-macromolecular complexes. When combined with X-ray crystallography, cryo-EM provides a routine approach for structurally characterizing the immune complexes formed between icosahedral viruses and their antibodies. In this review, recent advances in the structural understanding of virus-antibody interactions are outlined for whole virions with icosahedral T = pseudo 3 (picornaviruses) and T = 3 (flaviviruses) architectures, focusing on the dynamic nature of viral shells in different functional states. Glycoprotein complexes from pleomorphic enveloped viruses are also discussed as immune complex antigens. Improving our understanding of viral epitope structures using virus-based platforms would provide a fundamental road map for future vaccine development.
Collapse
Affiliation(s)
- Na Li
- CAS Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Wuhan, 430071, China.,Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhiqiang Li
- CAS Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Wuhan, 430071, China.,Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yan Fu
- CAS Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Wuhan, 430071, China.,Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Sheng Cao
- CAS Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Wuhan, 430071, China. .,Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China.
| |
Collapse
|
31
|
Durham ND, Agrawal A, Waltari E, Croote D, Zanini F, Fouch M, Davidson E, Smith O, Carabajal E, Pak JE, Doranz BJ, Robinson M, Sanz AM, Albornoz LL, Rosso F, Einav S, Quake SR, McCutcheon KM, Goo L. Broadly neutralizing human antibodies against dengue virus identified by single B cell transcriptomics. eLife 2019; 8:e52384. [PMID: 31820734 PMCID: PMC6927745 DOI: 10.7554/elife.52384] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 12/09/2019] [Indexed: 12/23/2022] Open
Abstract
Eliciting broadly neutralizing antibodies (bNAbs) against the four dengue virus serotypes (DENV1-4) that are spreading into new territories is an important goal of vaccine design. To define bNAb targets, we characterized 28 antibodies belonging to expanded and hypermutated clonal families identified by transcriptomic analysis of single plasmablasts from DENV-infected individuals. Among these, we identified J9 and J8, two somatically related bNAbs that potently neutralized DENV1-4. Mutagenesis studies showed that the major recognition determinants of these bNAbs are in E protein domain I, distinct from the only known class of human bNAbs against DENV with a well-defined epitope. B cell repertoire analysis from acute-phase peripheral blood suggested that J9 and J8 followed divergent somatic hypermutation pathways, and that a limited number of mutations was sufficient for neutralizing activity. Our study suggests multiple B cell evolutionary pathways leading to DENV bNAbs targeting a new epitope that can be exploited for vaccine design.
Collapse
Affiliation(s)
| | | | - Eric Waltari
- Chan Zuckerberg BiohubSan FranciscoUnited States
| | - Derek Croote
- Department of BioengineeringStanford UniversityStanfordUnited States
| | - Fabio Zanini
- Department of BioengineeringStanford UniversityStanfordUnited States
| | | | | | - Olivia Smith
- Chan Zuckerberg BiohubSan FranciscoUnited States
| | | | - John E Pak
- Chan Zuckerberg BiohubSan FranciscoUnited States
| | | | - Makeda Robinson
- Division of Infectious Diseases and Geographic Medicine, Department of MedicineStanford University School of MedicineStanfordUnited States
- Department of Microbiology and ImmunologyStanford University School of MedicineStanfordUnited States
| | - Ana M Sanz
- Clinical Research CenterFundación Valle del LiliCaliColombia
| | - Ludwig L Albornoz
- Pathology and Laboratory DepartmentFundación Valle del LiliCaliColombia
| | - Fernando Rosso
- Clinical Research CenterFundación Valle del LiliCaliColombia
- Department of Internal Medicine, Division of Infectious DiseasesFundación Valle del LiliCaliColombia
| | - Shirit Einav
- Division of Infectious Diseases and Geographic Medicine, Department of MedicineStanford University School of MedicineStanfordUnited States
- Department of Microbiology and ImmunologyStanford University School of MedicineStanfordUnited States
| | - Stephen R Quake
- Chan Zuckerberg BiohubSan FranciscoUnited States
- Department of BioengineeringStanford UniversityStanfordUnited States
| | | | - Leslie Goo
- Chan Zuckerberg BiohubSan FranciscoUnited States
- Vaccine and Infectious Disease DivisionFred Hutchinson Cancer Research CenterSeattleUnited States
| |
Collapse
|
32
|
Nasar S, Rashid N, Iftikhar S. Dengue proteins with their role in pathogenesis, and strategies for developing an effective anti-dengue treatment: A review. J Med Virol 2019; 92:941-955. [PMID: 31784997 DOI: 10.1002/jmv.25646] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Accepted: 11/26/2019] [Indexed: 12/16/2022]
Abstract
Dengue virus is an arbovirus belonging to class Flaviviridae Its clinical manifestation ranges from asymptomatic to extreme conditions (dengue hemorrhagic fever/dengue shock syndrome). A lot of research has been done on this ailment, yet there is no effective treatment available for the disease. This review provides the systematic understanding of all dengue proteins, role of its structural proteins (C-protein, E-protein, prM) in virus entry, assembly, and secretion in host cell, and nonstructural proteins (NS1, NS2a, NS2b, NS3, NS4a, NS4b, and NS5) in viral assembly, replication, and immune evasion during dengue progression and pathogenesis. Furthermore, the review has highlighted the controversies related to the only commercially available dengue vaccine, that is, Dengvaxia, and the risk associated with it. Lastly, it provides an insight regarding various approaches for developing an effective anti-dengue treatment.
Collapse
Affiliation(s)
- Sitara Nasar
- School of Biological Sciences, University of the Punjab, Lahore, Pakistan
| | - Naeem Rashid
- School of Biological Sciences, University of the Punjab, Lahore, Pakistan
| | - Saima Iftikhar
- School of Biological Sciences, University of the Punjab, Lahore, Pakistan
| |
Collapse
|
33
|
Blight J, Alves E, Reyes-Sandoval A. Considering Genomic and Immunological Correlates of Protection for a Dengue Intervention. Vaccines (Basel) 2019; 7:E203. [PMID: 31816907 PMCID: PMC6963661 DOI: 10.3390/vaccines7040203] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 11/25/2019] [Accepted: 11/27/2019] [Indexed: 01/18/2023] Open
Abstract
Over three billion are at risk of dengue infection with more than 100 million a year presenting with symptoms that can lead to deadly haemorrhagic disease. There are however no treatments available and the only licensed vaccine shows limited efficacy and is able to enhance the disease in some cases. These failures have mainly been due to the complex pathology and lack of understanding of the correlates of protection for dengue virus (DENV) infection. With increasing data suggesting both a protective and detrimental effect for antibodies and CD8 T-cells whilst having complex environmental dynamics. This review discusses the roles of genomic and immunological aspects of DENV infection, providing both a historical interpretation and fresh discussion on how this information can be used for the next generation of dengue interventions.
Collapse
Affiliation(s)
- Joshua Blight
- Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, Exhibition Road, South Kensington, London SW7 2AZ, UK; (J.B.); (E.A.)
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, The Henry Wellcome Building for Molecular Physiology, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Eduardo Alves
- Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, Exhibition Road, South Kensington, London SW7 2AZ, UK; (J.B.); (E.A.)
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, The Henry Wellcome Building for Molecular Physiology, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Arturo Reyes-Sandoval
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, The Henry Wellcome Building for Molecular Physiology, Roosevelt Drive, Oxford OX3 7BN, UK
| |
Collapse
|
34
|
Uppu DSSM, Turvey ME, Sharif ARM, Bidet K, He Y, Ho V, Tambe AD, Lescar J, Tan EY, Fink K, Chen J, Hammond PT. Temporal release of a three-component protein subunit vaccine from polymer multilayers. J Control Release 2019; 317:130-141. [PMID: 31756392 DOI: 10.1016/j.jconrel.2019.11.022] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 10/14/2019] [Accepted: 11/18/2019] [Indexed: 12/11/2022]
Abstract
Sustained antigen and adjuvant availability have been shown to improve antiviral immune responses following vaccination. Transcutaneous delivery of vaccines using microneedles has also shown promise and may be particularly relevant for mosquito-borne viruses. We aim to combine these traits to create a three-component Protein Subunit vaccine on Microneedle Arrays (PSMNs) for transcutaneous delivery using layer-by-layer (LbL) assembly. Polymer multilayer thin films were generated to co-deliver a model combination of three chemically distinct vaccine components, a dengue virus Envelope protein Domain III (EDIII) subunit antigen and two adjuvants, a double-stranded RNA (Poly (inosinic:cytidylic acid) (PolyI:C)) and an amphiphilic hexapeptide, Pam3CSK4. Following application of PSMNs to the skin, implanted thin films facilitated sustained and temporal release of individual vaccine components from polymer multilayers. By modulating LbL composition and architecture, component release profiles in the skin could be independently tuned to allow release of adjuvants and antigen from days up to two weeks. Uptake of antigen and adjuvant from implanted vaccine films by antigen-presenting cells was demonstrated using in vivo mouse and ex vivo human skin models. Overall, we believe that such modular vaccine strategies offer design principles for enhancing the immunogenicity of protein subunit vaccines.
Collapse
Affiliation(s)
- Divakara S S M Uppu
- Interdisciplinary Research Group in Infectious Diseases, Singapore-MIT Alliance for Research and Technology, Singapore
| | - Michelle E Turvey
- Interdisciplinary Research Group in Infectious Diseases, Singapore-MIT Alliance for Research and Technology, Singapore
| | - Abdul Rahim Mohammed Sharif
- Interdisciplinary Research Group in Infectious Diseases, Singapore-MIT Alliance for Research and Technology, Singapore
| | - Katell Bidet
- Interdisciplinary Research Group in Infectious Diseases, Singapore-MIT Alliance for Research and Technology, Singapore
| | - Yanpu He
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA; Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Victor Ho
- Singapore Immunology Network, Agency for Science Technology and Research, Singapore
| | - Anagha D Tambe
- Interdisciplinary Research Group in Infectious Diseases, Singapore-MIT Alliance for Research and Technology, Singapore
| | - Julien Lescar
- School of Biological Sciences, Nanyang Technology University, Singapore
| | - Ern Yu Tan
- Department of General Surgery, Tan Tock Seng Hospital, Singapore
| | - Katja Fink
- Singapore Immunology Network, Agency for Science Technology and Research, Singapore
| | - Jianzhu Chen
- Interdisciplinary Research Group in Infectious Diseases, Singapore-MIT Alliance for Research and Technology, Singapore; Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Paula T Hammond
- Interdisciplinary Research Group in Infectious Diseases, Singapore-MIT Alliance for Research and Technology, Singapore; Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA; Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
| |
Collapse
|
35
|
Tracking the polyclonal neutralizing antibody response to a dengue virus serotype 1 type-specific epitope across two populations in Asia and the Americas. Sci Rep 2019; 9:16258. [PMID: 31700029 PMCID: PMC6838341 DOI: 10.1038/s41598-019-52511-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 10/18/2019] [Indexed: 01/22/2023] Open
Abstract
The four dengue virus serotypes (DENV1-4) cause major public health problems worldwide. Highly neutralizing type-specific human monoclonal antibodies (hmAbs) target conformation-dependent epitopes on the DENV envelope protein, including 1F4, a DENV1 type-specific hmAb. Using a recombinant DENV2 virus displaying the DENV1 1F4 epitope (rDENV2/1), we measured the proportion and kinetics of DENV1 neutralizing antibodies targeting the 1F4 epitope in individuals living in Asia and the Americas where different DENV1 genotypes were circulating. Samples from 20 individuals were analyzed 3 and 18 months post-primary DENV1 infection, alongside samples from 4 individuals collected annually for four years post-primary DENV1 infection, from two studies in Nicaragua. We also analyzed convalescent post-primary DENV1 plasma samples from Sri Lankan individuals. We found that neutralizing antibodies recognizing the 1F4 epitope vary in prevalence across both populations and were detected from 20 days to four years post-infection. Additionally, both populations displayed substantial variability, with a range of high to low proportions of DENV1 type-specific neutralizing antibodies recognizing the 1F4 epitope seen across individuals. Thus, the 1F4 epitope is a major but not exclusive target of type-specific neutralizing antibodies post-primary infection with different DENV1 genotypes in Asia and Latin America, and additional epitopes likely contribute to type-specific neutralization of DENV1.
Collapse
|
36
|
Tuan Vu T, Clapham H, Huynh VTT, Vo Thi L, Le Thi D, Vu NT, Nguyen GT, Huynh TTX, Duong KTH, Tran VT, Huynh HLA, Le Huynh DT, Huynh TLP, Nguyen TTV, Nguyen NM, Luong TTH, Phong NT, Nguyen CVV, Gough G, Wills B, Carrington LB, Simmons CP. Blockade of dengue virus transmission from viremic blood to Aedes aegypti mosquitoes using human monoclonal antibodies. PLoS Negl Trop Dis 2019; 13:e0007142. [PMID: 31675360 PMCID: PMC6853333 DOI: 10.1371/journal.pntd.0007142] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Revised: 11/13/2019] [Accepted: 09/25/2019] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Dengue is the most prevalent arboviral disease of humans. Virus neutralizing antibodies are likely to be critical for clinical immunity after vaccination or natural infection. A number of human monoclonal antibodies (mAbs) have previously been characterized as able to neutralize the infectivity of dengue virus (DENV) for mammalian cells in cell-culture systems. METHODOLOGY/PRINCIPLE FINDINGS We tested the capacity of 12 human mAbs, each of which had previously been shown to neutralize DENV in cell-culture systems, to abrogate the infectiousness of dengue patient viremic blood for mosquitoes. Seven of the twelve mAbs (1F4, 14c10, 2D22, 1L12, 5J7, 747(4)B7, 753(3)C10), almost all of which target quaternary epitopes, inhibited DENV infection of Ae. aegypti. The mAbs 14c10, 747(4)B7 and 753(3)C10 could all inhibit transmission of DENV in low microgram per mL concentrations. An Fc-disabled variant of 14c10 was as potent as its parent mAb. CONCLUSIONS/SIGNIFICANCE The results demonstrate that mAbs can neutralize infectious DENV derived from infected human cells, in the matrix of human blood. Coupled with previous evidence of their ability to prevent DENV infection of mammalian cells, such mAbs could be considered attractive antibody classes to elicit with dengue vaccines, or alternatively, for consideration as therapeutic candidates.
Collapse
Affiliation(s)
- Trung Tuan Vu
- Oxford University Clinical Research Unit, District 5, Ho Chi Minh City, Vietnam
- Centre for Tropical Medicine and Global Health, University of Oxford, Headington, Oxford, United Kingdom
- * E-mail:
| | - Hannah Clapham
- Oxford University Clinical Research Unit, District 5, Ho Chi Minh City, Vietnam
- Centre for Tropical Medicine and Global Health, University of Oxford, Headington, Oxford, United Kingdom
| | - Van Thi Thuy Huynh
- Oxford University Clinical Research Unit, District 5, Ho Chi Minh City, Vietnam
| | - Long Vo Thi
- Oxford University Clinical Research Unit, District 5, Ho Chi Minh City, Vietnam
| | - Dui Le Thi
- Oxford University Clinical Research Unit, District 5, Ho Chi Minh City, Vietnam
| | - Nhu Tuyet Vu
- Oxford University Clinical Research Unit, District 5, Ho Chi Minh City, Vietnam
| | - Giang Thi Nguyen
- Oxford University Clinical Research Unit, District 5, Ho Chi Minh City, Vietnam
| | | | - Kien Thi Hue Duong
- Oxford University Clinical Research Unit, District 5, Ho Chi Minh City, Vietnam
| | - Vi Thuy Tran
- Oxford University Clinical Research Unit, District 5, Ho Chi Minh City, Vietnam
| | - Huy Le Anh Huynh
- Oxford University Clinical Research Unit, District 5, Ho Chi Minh City, Vietnam
| | - Duyen Thi Le Huynh
- Oxford University Clinical Research Unit, District 5, Ho Chi Minh City, Vietnam
| | | | - Thuy Thi Van Nguyen
- Oxford University Clinical Research Unit, District 5, Ho Chi Minh City, Vietnam
| | - Nguyet Minh Nguyen
- Oxford University Clinical Research Unit, District 5, Ho Chi Minh City, Vietnam
| | - Tai Thi Hue Luong
- Hospital for Tropical Diseases, District 5, Ho Chi Minh City, Vietnam
| | | | | | - Gerald Gough
- Biopharm Discovery, GlaxoSmithKline, Stevenage, United Kingdom
| | - Bridget Wills
- Oxford University Clinical Research Unit, District 5, Ho Chi Minh City, Vietnam
- Centre for Tropical Medicine and Global Health, University of Oxford, Headington, Oxford, United Kingdom
| | - Lauren B. Carrington
- Oxford University Clinical Research Unit, District 5, Ho Chi Minh City, Vietnam
- Centre for Tropical Medicine and Global Health, University of Oxford, Headington, Oxford, United Kingdom
| | - Cameron P. Simmons
- Oxford University Clinical Research Unit, District 5, Ho Chi Minh City, Vietnam
- Centre for Tropical Medicine and Global Health, University of Oxford, Headington, Oxford, United Kingdom
- Institute for Vector-Borne Disease, Monash University, Clayton, Australia
| |
Collapse
|
37
|
Lim XN, Shan C, Marzinek JK, Dong H, Ng TS, Ooi JSG, Fibriansah G, Wang J, Verma CS, Bond PJ, Shi PY, Lok SM. Molecular basis of dengue virus serotype 2 morphological switch from 29°C to 37°C. PLoS Pathog 2019; 15:e1007996. [PMID: 31536610 PMCID: PMC6752767 DOI: 10.1371/journal.ppat.1007996] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 07/22/2019] [Indexed: 01/02/2023] Open
Abstract
The ability of DENV2 to display different morphologies (hence different antigenic properties) complicates vaccine and therapeutics development. Previous studies showed most strains of laboratory adapted DENV2 particles changed from smooth to “bumpy” surfaced morphology when the temperature is switched from 29°C at 37°C. Here we identified five envelope (E) protein residues different between two alternative passage history DENV2 NGC strains exhibiting smooth or bumpy surface morphologies. Several mutations performed on the smooth DENV2 infectious clone destabilized the surface, as observed by cryoEM. Molecular dynamics simulations demonstrated how chemically subtle substitution at various positions destabilized dimeric interactions between E proteins. In contrast, three out of four DENV2 clinical isolates showed a smooth surface morphology at 37°C, and only at high fever temperature (40°C) did they become “bumpy”. These results imply vaccines should contain particles representing both morphologies. For prophylactic and therapeutic treatments, this study also informs on which types of antibodies should be used at different stages of an infection, i.e., those that bind to monomeric E proteins on the bumpy surface or across multiple E proteins on the smooth surfaced virus. DENV2 particles have been shown to change their morphologies (compact smooth to loose bumpy surfaced) when temperature is switched from 28°C to 37°C. We used two DENV2 viruses both belonging to the same strain designation but with a different passage history—one of which exhibited the smooth surfaced morphology while the other was bumpy surfaced, observed by cryoEM. We mutated residues in the E protein of the DENV2 infectious clone that has the smooth surfaced morphology to determine if any could result in a bumpy morphology. Results showed several different mutations could lead to this change. Using molecular dynamics simulations, we showed how these mutations likely destabilize the E protein dimeric interactions. We investigated whether the bumpy morphology also occurs in DENV2 clinical isolates, and showed that these viruses can exhibit both morphologies, indicating that vaccine and therapeutics development should target both virus forms.
Collapse
Affiliation(s)
- Xin-Ni Lim
- Program in Emerging Infectious Diseases, Duke-National University of Singapore Medical School, Singapore, Singapore
- Centre for Bioimaging Sciences, National University of Singapore, Singapore, Singapore
| | - Chao Shan
- Novartis Institute for Tropical Diseases, Singapore, Singapore
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Jan K. Marzinek
- Bioinformatics Institute, Agency of Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Hongping Dong
- Novartis Institute for Tropical Diseases, Singapore, Singapore
| | - Thiam Seng Ng
- Program in Emerging Infectious Diseases, Duke-National University of Singapore Medical School, Singapore, Singapore
- Centre for Bioimaging Sciences, National University of Singapore, Singapore, Singapore
| | - Justin S. G. Ooi
- Program in Emerging Infectious Diseases, Duke-National University of Singapore Medical School, Singapore, Singapore
- Centre for Bioimaging Sciences, National University of Singapore, Singapore, Singapore
| | - Guntur Fibriansah
- Program in Emerging Infectious Diseases, Duke-National University of Singapore Medical School, Singapore, Singapore
- Centre for Bioimaging Sciences, National University of Singapore, Singapore, Singapore
| | - Jiaqi Wang
- Program in Emerging Infectious Diseases, Duke-National University of Singapore Medical School, Singapore, Singapore
- Centre for Bioimaging Sciences, National University of Singapore, Singapore, Singapore
| | - Chandra S. Verma
- Bioinformatics Institute, Agency of Science, Technology and Research (A*STAR), Singapore, Singapore
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Peter J. Bond
- Bioinformatics Institute, Agency of Science, Technology and Research (A*STAR), Singapore, Singapore
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
- * E-mail: (PJB); (PS); (SL)
| | - Pei-Yong Shi
- Novartis Institute for Tropical Diseases, Singapore, Singapore
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas, United States of America
- Sealy Center for Structural Biology & Molecular Biophysics, University of Texas Medical Branch, Texas, United States of America
- * E-mail: (PJB); (PS); (SL)
| | - Shee-mei Lok
- Program in Emerging Infectious Diseases, Duke-National University of Singapore Medical School, Singapore, Singapore
- Centre for Bioimaging Sciences, National University of Singapore, Singapore, Singapore
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
- * E-mail: (PJB); (PS); (SL)
| |
Collapse
|
38
|
Swanstrom JA, Henein S, Plante JA, Yount BL, Widman DG, Gallichotte EN, Dean HJ, Osorio JE, Partidos CD, de Silva AM, Baric RS. Analyzing the Human Serum Antibody Responses to a Live Attenuated Tetravalent Dengue Vaccine Candidate. J Infect Dis 2019; 217:1932-1941. [PMID: 29800370 DOI: 10.1093/infdis/jiy063] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Background Dengue virus serotypes 1-4 (DENV-1-4) are the most common vector-borne viral pathogens of humans and the etiological agents of dengue fever and dengue hemorrhagic syndrome. A live-attenuated tetravalent dengue vaccine (TDV) developed by Takeda Vaccines has recently progressed to phase 3 safety and efficacy evaluation. Methods We analyzed the qualitative features of the neutralizing antibody (nAb) response induced in naive and DENV-immune individuals after TDV administration. Using DENV-specific human monoclonal antibodies (mAbs) and recombinant DENV displaying different serotype-specific Ab epitopes, we mapped the specificity of TDV-induced nAbs against DENV-1-3. Results Nearly all subjects had high levels of DENV-2-specific nAbs directed to epitopes centered on domain III of the envelope protein. In some individuals, the vaccine induced nAbs that tracked with a DENV-1-specific neutralizing epitope centered on domain I of the envelope protein. The vaccine induced binding Abs directed to a DENV-3 type-specific neutralizing epitope, but findings of mapping of DENV-3 type-specific nAbs were inconclusive. Conclusion Here we provide qualitative measures of the magnitude and epitope specificity of the nAb responses to TDV. This information will be useful for understanding the performance of TDV in clinical trials and for identifying correlates of protective immunity.
Collapse
Affiliation(s)
- Jesica A Swanstrom
- Department of Epidemiology, School of Public Health, University of North Carolina, Chapel Hill
| | - Sandra Henein
- Department of Microbiology and Immunology, School of Medicine, University of North Carolina, Chapel Hill
| | - Jessica A Plante
- Department of Epidemiology, School of Public Health, University of North Carolina, Chapel Hill
| | - Boyd L Yount
- Department of Epidemiology, School of Public Health, University of North Carolina, Chapel Hill
| | - Douglas G Widman
- Department of Epidemiology, School of Public Health, University of North Carolina, Chapel Hill
| | - Emily N Gallichotte
- Department of Microbiology and Immunology, School of Medicine, University of North Carolina, Chapel Hill
| | | | | | | | - Aravinda M de Silva
- Department of Microbiology and Immunology, School of Medicine, University of North Carolina, Chapel Hill
| | - Ralph S Baric
- Department of Epidemiology, School of Public Health, University of North Carolina, Chapel Hill.,Department of Microbiology and Immunology, School of Medicine, University of North Carolina, Chapel Hill
| |
Collapse
|
39
|
A protective Zika virus E-dimer-based subunit vaccine engineered to abrogate antibody-dependent enhancement of dengue infection. Nat Immunol 2019; 20:1291-1298. [PMID: 31477918 DOI: 10.1038/s41590-019-0477-z] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 07/22/2019] [Indexed: 11/08/2022]
Abstract
Infections with dengue virus (DENV) and Zika virus (ZIKV) can induce cross-reactive antibody responses. Two immunodominant epitopes-one to precursor membrane protein and one to the fusion loop epitope on envelope (E) protein-are recognized by cross-reactive antibodies1-3 that are not only poorly neutralizing, but can also promote increased viral replication and disease severity via Fcγ receptor-mediated infection of myeloid cells-a process termed antibody-dependent enhancement (ADE)1,4,5. ADE is a significant concern for both ZIKV and DENV vaccines as the induction of poorly neutralizing cross-reactive antibodies may prime an individual for ADE on natural infection. In this report, we describe the design and production of covalently stabilized ZIKV E dimers, which lack precursor membrane protein and do not expose the immunodominant fusion loop epitope. Immunization of mice with ZIKV E dimers induces dimer-specific antibodies, which protect against ZIKV challenge during pregnancy. Importantly, the ZIKV E-dimer-induced response does not cross-react with DENV or induce ADE of DENV infection.
Collapse
|
40
|
Galula JU, Salem GM, Chang GJJ, Chao DY. Does structurally-mature dengue virion matter in vaccine preparation in post-Dengvaxia era? Hum Vaccin Immunother 2019; 15:2328-2336. [PMID: 31314657 PMCID: PMC6816432 DOI: 10.1080/21645515.2019.1643676] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The unexpectedly low vaccine efficacy of Dengvaxia®, developed by Sanofi Pasteur, and a higher risk of severe diseases after vaccination among dengue-naive children or children younger than 6 years old, have cast skepticism about the safety of dengue vaccination resulting in the suspension of school-based immunization programs in the Philippines. The absence of immune correlates of protection from dengue virus (DENV) infection hampers the development of other potential DENV vaccines. While tetravalent live-attenuated tetravalent vaccines (LATVs), which mimic natural infection by inducing both cellular and humoral immune responses, are still currently favored, developing a vaccine that provides a balanced immunity to all four DENV serotypes remains a challenge. With the recently advanced understanding of virion structure and B cell immune responses from naturally infected DENV patients, two points of view in developing a next-generation dengue vaccine emerged: one is to induce potent, type-specific neutralizing antibodies (NtAbs) recognizing quaternary structure-dependent epitopes by having four components of vaccine strains replicate equivalently; the other is to induce protective and broadly NtAbs against the four serotypes of DENV with a universal vaccine. This article reviews the studies related to these issues and the current knowledge gap that needs to be filled in.
Collapse
Affiliation(s)
- Jedhan Ucat Galula
- Graduate Institute of Microbiology and Public Health, College of Veterinary Medicine, National Chung Hsing University , Taichung , Taiwan
| | - Gielenny M Salem
- Graduate Institute of Microbiology and Public Health, College of Veterinary Medicine, National Chung Hsing University , Taichung , Taiwan
| | - Gwong-Jen J Chang
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, US Department of Health and Human Services , Fort Collins , CO , USA
| | - Day-Yu Chao
- Graduate Institute of Microbiology and Public Health, College of Veterinary Medicine, National Chung Hsing University , Taichung , Taiwan
| |
Collapse
|
41
|
Stass R, Ng WM, Kim YC, Huiskonen JT. Structures of enveloped virions determined by cryogenic electron microscopy and tomography. Adv Virus Res 2019; 105:35-71. [PMID: 31522708 PMCID: PMC7112279 DOI: 10.1016/bs.aivir.2019.07.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Enveloped viruses enclose their genomes inside a lipid bilayer which is decorated by membrane proteins that mediate virus entry. These viruses display a wide range of sizes, morphologies and symmetries. Spherical viruses are often isometric and their envelope proteins follow icosahedral symmetry. Filamentous and pleomorphic viruses lack such global symmetry but their surface proteins may display locally ordered assemblies. Determining the structures of enveloped viruses, including the envelope proteins and their protein-protein interactions on the viral surface, is of paramount importance. These structures can reveal how the virions are assembled and released by budding from the infected host cell, how the progeny virions infect new cells by membrane fusion, and how antibodies bind surface epitopes to block infection. In this chapter, we discuss the uses of cryogenic electron microscopy (cryo-EM) in elucidating structures of enveloped virions. Starting from a detailed outline of data collection and processing strategies, we highlight how cryo-EM has been successfully utilized to provide unique insights into enveloped virus entry, assembly, and neutralization.
Collapse
Affiliation(s)
- Robert Stass
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Weng M Ng
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Young Chan Kim
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Juha T Huiskonen
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom; Helsinki Institute of Life Science HiLIFE and Research Programme in Molecular and Integrative Biosciences, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland.
| |
Collapse
|
42
|
Goncalves A, Peeling RW, Chu MC, Gubler DJ, de Silva AM, Harris E, Murtagh M, Chua A, Rodriguez W, Kelly C, Wilder-Smith A. Innovative and New Approaches to Laboratory Diagnosis of Zika and Dengue: A Meeting Report. J Infect Dis 2019; 217:1060-1068. [PMID: 29294035 DOI: 10.1093/infdis/jix678] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 12/22/2017] [Indexed: 12/30/2022] Open
Abstract
Epidemics of dengue, Zika, and other arboviral diseases are increasing in frequency and severity. Current efforts to rapidly identify and manage these epidemics are limited by the short diagnostic window in acute infection, the extensive serologic cross-reactivity among flaviviruses, and the lack of point-of-care diagnostic tools to detect these viral species in primary care settings. The Partnership for Dengue Control organized a workshop to review the current landscape of Flavivirus diagnostic tools, identified current gaps, and developed strategies to accelerate the adoption of promising novel technologies into national programs. The rate-limiting step to bringing new diagnostic tools to the market is access to reference materials and well-characterized clinical samples to facilitate performance evaluation. We suggest the creation of an international laboratory-response consortium for flaviviruses with a decentralized biobank of well-characterized samples to facilitate assay validation. Access to proficiency panels are needed to ensure quality control, in additional to in-country capacity building.
Collapse
Affiliation(s)
| | | | - May C Chu
- Department of Epidemiology, Colorado School of Public Health, University of Colorado, Anschutz Medical Center, Aurora
| | - Duane J Gubler
- Emerging Infectious Diseases Program, Duke-NUS Medical School, Singapore
| | - Aravinda M de Silva
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill
| | - Eva Harris
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley
| | | | | | | | | | - Annelies Wilder-Smith
- Lee Kong Chian School of Medicine, Singapore.,Institute of Public Health, University of Heidelberg, Germany.,Department of Global Health and Epidemiology, University of Umea, Sweden
| |
Collapse
|
43
|
Mimicking immune signatures of flavivirus infection with targeted adjuvants improves dengue subunit vaccine immunogenicity. NPJ Vaccines 2019; 4:27. [PMID: 31285858 PMCID: PMC6592935 DOI: 10.1038/s41541-019-0119-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 06/03/2019] [Indexed: 12/28/2022] Open
Abstract
Neutralizing antibodies (nAbs) are a critical component for protection against dengue virus (DENV) infection, but little is known about the immune mechanisms governing their induction and whether such mechanisms can be harnessed for vaccine development. In this study, we profiled the early immune responses to flaviviruses in human peripheral blood mononuclear cells and screened a panel of toll-like receptor (TLR) agonists that stimulate the same immune signatures. Monocyte/macrophage-driven inflammatory responses and interferon responses were characteristics of flavivirus infection and associated with induction of nAbs in humans immunized with the yellow fever vaccine YF-17D. The signatures were best reproduced by the combination of TLR agonists Pam3CSK4 and PolyI:C (PP). Immunization of both mice and macaques with a poorly immunogenic recombinant DENV-2 envelope domain III (EDIII) induced more consistent nAb and CD4+ T-cell responses with PP compared to alum plus monophosphoryl lipid A. Induction of nAbs by PP required interferon-mediated signals in macrophages in mice. However, EDIII + PP vaccination only provided partial protection against viral challenge. These results provide insights into mechanisms underlying nAb induction and a basis for further improving antigen/adjuvant combinations for dengue vaccine development. Neutralizing antibodies (nAb) are associated with protection from symptomatic dengue virus infection and current dengue vaccine development aims to elicit a strong nAb response. However, immune mechanisms underlying nAb development in response to dengue infection or vaccination are not completely understood. In this study, led by Jianzhu Chen from the Interdisciplinary Research Group in Infectious Diseases in Singapore, researchers identify a combination of two TLR agonists that elicits better nAb responses than currently used adjuvants. Comparison of transcriptomes of human PBMCs infected with flaviviruses identifies an immune signature that is associated with induction of nAbs and a similar immune signature can be elicited with a combination of two TLR agonists. Vaccination of mice or non-human primates using these two TLR agonists as adjuvant elicits a strong nAb response. However, this vaccination regimen could not confer protection in the animals, suggesting that further improvements of this vaccine candidate will be necessary.
Collapse
|
44
|
Kudlacek ST, Metz SW. Focused dengue vaccine development: outwitting nature's design. Pathog Dis 2019; 77:5307883. [PMID: 30726906 DOI: 10.1093/femspd/ftz003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2018] [Accepted: 01/15/2019] [Indexed: 12/28/2022] Open
Abstract
The four DENV serotypes are mosquito-borne pathogens that belong to the Flavivirus genus. These viruses present a major global health burden, being endemic in over 120 countries, causing ∼390 million reported infections yearly, with clinical symptoms ranging from mild fever to severe and potentially fatal hemorrhagic syndromes. Development of a safe and efficacious DENV vaccine is challenging because of the need to induce immunity against all four serotypes simultaneously, as immunity against one serotype can potentially enhance disease caused by a heterotypic secondary infection. So far, live-virus particle-based vaccine approaches struggle with inducing protective tetravalent immunity, while recombinant subunit approaches that use the envelope protein (E) as the major antigen, are gaining promise in preclinical studies. However, E-based subunits require further development and characterization to be used as effective vaccine antigens against DENV. In this review, we will address the shortcomings of recombinant E-based antigens and will discuss potential solutions to enhance E-based subunit antigen immunogenicity and vaccine efficacy.
Collapse
Affiliation(s)
- Stephan T Kudlacek
- Department of Biochemistry and Biophysics, University of North Carolina, 125 Mason Farm Road, 6230E Marisco Hall, Chapel Hill, NC 27599, USA
| | - Stefan W Metz
- Department of Microbiology and Immunology, University of North Carolina, 125 Mason Farm Road, 6230E Marisco Hall, Chapel Hill, NC 27599, USA
| |
Collapse
|
45
|
Li L, Meng W, Horton M, DiStefano DR, Thoryk EA, Pfaff JM, Wang Q, Salazar GT, Barnes T, Doranz BJ, Bett AJ, Casimiro DR, Vora KA, An Z, Zhang N. Potent neutralizing antibodies elicited by dengue vaccine in rhesus macaque target diverse epitopes. PLoS Pathog 2019; 15:e1007716. [PMID: 31170257 PMCID: PMC6553876 DOI: 10.1371/journal.ppat.1007716] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 03/19/2019] [Indexed: 01/11/2023] Open
Abstract
There is still no safe and effective vaccine against dengue virus infection. Epidemics of dengue virus infection are increasingly a threat to human health around the world. Antibodies generated in response to dengue infection have been shown to impact disease development and effectiveness of dengue vaccine. In this study, we investigated monoclonal antibody responses to an experimental dengue vaccine in rhesus macaques. Variable regions of both heavy chain (VH) and light chain (VL) were cloned from single antibody-secreting B cells. A total of 780 monoclonal antibodies (mAbs) composed of paired VH and VL were characterized. Results show that the vaccination induces mAbs with diverse germline sequences and a wide range of binding affinities. Six potent neutralizing mAbs were identified among 130 dengue envelope protein binders. Critical amino acids for each neutralizing antibody binding to the dengue envelope protein were identified by alanine scanning of mutant libraries. Diverse epitopes were identified, including epitopes on the lateral ridge of DIII, the I-III hinge, the bc loop adjacent to the fusion loop of DII, and the β-strands and loops of DI. Significantly, one of the neutralizing mAbs has a previously unknown epitope in DII at the interface of the envelope and membrane protein and is capable of neutralizing all four dengue serotypes. Taken together, the results of this study not only provide preclinical validation for the tested experimental vaccine, but also shed light on a potential application of the rhesus macaque model for better dengue vaccine evaluation and design of vaccines and immunization strategies. Dengue virus (DENV) is a leading cause of human illness in the tropics and subtropics, with about 40% of the world’s population living in areas at risk for infection. There are four DENV serotypes. Patients who have previously been infected by one dengue serotype may develop more severe symptoms such as bleeding and endothelial leakage upon secondary infection with another dengue serotype. This study reports the extensive cloning and analysis of 780 monoclonal antibodies (mAbs) from single B cells of rhesus macaques after immunization with an experimental dengue vaccine. We identified a panel of potent neutralizing mAbs with diverse epitopes on the DENV envelope protein. Antibodies in this panel were found to bind to the lateral ridge of DIII, the I-III hinge, the bc loop adjacent to the fusion loop of DII, and the β-strands and the loops of DI. We also isolated one mAb (d448) that can neutralize all four dengue serotypes and binds to a novel epitope at the interface of the DENV envelope and membrane proteins. Further investigation of these neutralizing monoclonal antibodies is warranted for better vaccine efficacy evaluation and vaccine design.
Collapse
Affiliation(s)
- Leike Li
- Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, Texas, United States of America
| | - Weixu Meng
- Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, Texas, United States of America
| | - Melanie Horton
- Department of Infectious Diseases and Vaccines Research, Merck Research Laboratories, Merck and Co. Inc., Kenilworth, New Jersey, United States of America
| | - Daniel R. DiStefano
- Department of Infectious Diseases and Vaccines Research, Merck Research Laboratories, Merck and Co. Inc., Kenilworth, New Jersey, United States of America
| | - Elizabeth A. Thoryk
- Department of Infectious Diseases and Vaccines Research, Merck Research Laboratories, Merck and Co. Inc., Kenilworth, New Jersey, United States of America
| | - Jennifer M. Pfaff
- Integral Molecular, Philadelphia, Pennsylvania, United States of America
| | - Qihui Wang
- Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, Texas, United States of America
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Georgina T. Salazar
- Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, Texas, United States of America
| | - Trevor Barnes
- Integral Molecular, Philadelphia, Pennsylvania, United States of America
| | - Benjamin J. Doranz
- Integral Molecular, Philadelphia, Pennsylvania, United States of America
| | - Andrew J. Bett
- Department of Infectious Diseases and Vaccines Research, Merck Research Laboratories, Merck and Co. Inc., Kenilworth, New Jersey, United States of America
| | - Danilo R. Casimiro
- Department of Infectious Diseases and Vaccines Research, Merck Research Laboratories, Merck and Co. Inc., Kenilworth, New Jersey, United States of America
| | - Kalpit A. Vora
- Department of Infectious Diseases and Vaccines Research, Merck Research Laboratories, Merck and Co. Inc., Kenilworth, New Jersey, United States of America
- * E-mail: (KV); (ZA); (NZ)
| | - Zhiqiang An
- Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, Texas, United States of America
- * E-mail: (KV); (ZA); (NZ)
| | - Ningyan Zhang
- Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, Texas, United States of America
- * E-mail: (KV); (ZA); (NZ)
| |
Collapse
|
46
|
Dowd KA, Pierson TC. The Many Faces of a Dynamic Virion: Implications of Viral Breathing on Flavivirus Biology and Immunogenicity. Annu Rev Virol 2019; 5:185-207. [PMID: 30265634 DOI: 10.1146/annurev-virology-092917-043300] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Flaviviruses are arthropod-borne RNA viruses that are a significant threat to global health due to their widespread distribution, ability to cause severe disease in humans, and capacity for explosive spread following introduction into new regions. Members of this genus include dengue, tick-borne encephalitis, yellow fever, and Zika viruses. Vaccination has been a highly successful means to control flaviviruses, and neutralizing antibodies are an important component of a protective immune response. High-resolution structures of flavivirus structural proteins and virions, alone and in complex with antibodies, provide a detailed understanding of viral fusion mechanisms and virus-antibody interactions. However, mounting evidence suggests these structures provide only a snapshot of an otherwise structurally dynamic virus particle. The contribution of the structural ensemble arising from viral breathing to the biology, antigenicity, and immunity of flaviviruses is discussed, including implications for the development and evaluation of flavivirus vaccines.
Collapse
Affiliation(s)
- Kimberly A Dowd
- Viral Pathogenesis Section, Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA; ,
| | - Theodore C Pierson
- Viral Pathogenesis Section, Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA; ,
| |
Collapse
|
47
|
Collins MH. Serologic Tools and Strategies to Support Intervention Trials to Combat Zika Virus Infection and Disease. Trop Med Infect Dis 2019; 4:E68. [PMID: 31010134 PMCID: PMC6632022 DOI: 10.3390/tropicalmed4020068] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 04/11/2019] [Accepted: 04/15/2019] [Indexed: 12/30/2022] Open
Abstract
Zika virus is an emerging mosquito-borne flavivirus that recently caused a large epidemic in Latin America characterized by novel disease phenotypes, including Guillain-Barré syndrome, sexual transmission, and congenital anomalies, such as microcephaly. This epidemic, which was declared an international public health emergency by the World Health Organization, has highlighted shortcomings in our current understanding of, and preparation for, emerging infectious diseases in general, as well as challenges that are specific to Zika virus infection. Vaccine development for Zika virus has been a high priority of the public health response, and several candidates have shown promise in pre-clinical and early phase clinical trials. The optimal selection and implementation of imperfect serologic assays are among the crucial issues that must be addressed in order to advance Zika vaccine development. Here, I review key considerations for how best to incorporate into Zika vaccine trials the existing serologic tools, as well as those on the horizon. Beyond that, this discussion is relevant to other intervention strategies to combat Zika and likely other emerging infectious diseases.
Collapse
Affiliation(s)
- Matthew H Collins
- Hope Clinic of the Emory Vaccine Center, Division of Infectious Diseases, Department of Medicine, School of Medicine, Emory University, Decatur, GA 30030, USA.
| |
Collapse
|
48
|
Collins MH, Tu HA, Gimblet-Ochieng C, Liou GJA, Jadi RS, Metz SW, Thomas A, McElvany BD, Davidson E, Doranz BJ, Reyes Y, Bowman NM, Becker-Dreps S, Bucardo F, Lazear HM, Diehl SA, de Silva AM. Human antibody response to Zika targets type-specific quaternary structure epitopes. JCI Insight 2019; 4:124588. [PMID: 30996133 DOI: 10.1172/jci.insight.124588] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 03/07/2019] [Indexed: 12/22/2022] Open
Abstract
The recent Zika virus (ZIKV) epidemic in the Americas has revealed rare but serious manifestations of infection. ZIKV has emerged in regions endemic for dengue virus (DENV), a closely related mosquito-borne flavivirus. Cross-reactive antibodies confound studies of ZIKV epidemiology and pathogenesis. The immune responses to ZIKV may be different in people, depending on their DENV immune status. Here, we focus on the human B cell and antibody response to ZIKV as a primary flavivirus infection to define the properties of neutralizing and protective antibodies generated in the absence of preexisting immunity to DENV. The plasma antibody and memory B cell response is highly ZIKV type-specific, and ZIKV-neutralizing antibodies mainly target quaternary structure epitopes on the viral envelope. To map viral epitopes targeted by protective antibodies, we isolated 2 type-specific monoclonal antibodies (mAbs) from a ZIKV case. Both mAbs were strongly neutralizing in vitro and protective in vivo. The mAbs recognize distinct epitopes centered on domains I and II of the envelope protein. We also demonstrate that the epitopes of these mAbs define antigenic regions commonly targeted by plasma antibodies in individuals from endemic and nonendemic regions who have recovered from ZIKV infections.
Collapse
Affiliation(s)
- Matthew H Collins
- Department of Medicine, Emory University, Atlanta, Georgia, USA, and Hope Clinic of the Emory Vaccine Center, Division of Infectious Diseases, Department of Medicine, School of Medicine, Emory University, Decatur, Georgia, USA.,Department of Medicine, Division of Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA
| | - Huy A Tu
- Cellular, Molecular, and Biomedical Sciences Program, University of Vermont, Burlington, Vermont, USA.,Vaccine Testing Center, Department of Microbiology and Molecular Genetics, Larner College of Medicine, University of Vermont, Burlington, Vermont, USA
| | - Ciara Gimblet-Ochieng
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA
| | - Guei-Jiun Alice Liou
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA
| | - Ramesh S Jadi
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA
| | - Stefan W Metz
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA
| | - Ashlie Thomas
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA
| | - Benjamin D McElvany
- Vaccine Testing Center, Department of Microbiology and Molecular Genetics, Larner College of Medicine, University of Vermont, Burlington, Vermont, USA
| | - Edgar Davidson
- Integral Molecular, Inc., Philadelphia, Pennsylvania, USA
| | | | - Yaoska Reyes
- Department of Microbiology, Faculty of Medical Sciences, National Autonomous University of León, Nicaragua
| | - Natalie M Bowman
- Department of Medicine, Division of Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA
| | - Sylvia Becker-Dreps
- Departments of Family Medicine and Epidemiology, University of North Carolina at Chapel Hill, Schools of Medicine and Public Health, Chapel Hill, North Carolina, USA
| | - Filemón Bucardo
- Department of Microbiology, Faculty of Medical Sciences, National Autonomous University of León, Nicaragua
| | - Helen M Lazear
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA
| | - Sean A Diehl
- Cellular, Molecular, and Biomedical Sciences Program, University of Vermont, Burlington, Vermont, USA.,Vaccine Testing Center, Department of Microbiology and Molecular Genetics, Larner College of Medicine, University of Vermont, Burlington, Vermont, USA
| | - Aravinda M de Silva
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA
| |
Collapse
|
49
|
Biotherapeutic Antibody Subunit LC-MS and Peptide Mapping LC-MS Measurements to Study Possible Biotransformation and Critical Quality Attributes In Vivo. J Pharm Sci 2019; 108:1415-1422. [DOI: 10.1016/j.xphs.2018.11.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 10/29/2018] [Accepted: 11/14/2018] [Indexed: 12/13/2022]
|
50
|
Nivarthi UK, Tu HA, Delacruz MJ, Swanstrom J, Patel B, Durbin AP, Whitehead SS, Pierce KK, Kirkpatrick BD, Baric RS, Nguyen N, Emerling DE, de Silva AM, Diehl SA. Longitudinal analysis of acute and convalescent B cell responses in a human primary dengue serotype 2 infection model. EBioMedicine 2019; 41:465-478. [PMID: 30857944 PMCID: PMC6444124 DOI: 10.1016/j.ebiom.2019.02.060] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 02/18/2019] [Accepted: 02/28/2019] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND Acute viral infections induce a rapid and transient increase in antibody-secreting plasmablasts. At convalescence, memory B cells (MBC) and long-lived plasma cells (LLPC) are responsible for long-term humoral immunity. Following an acute viral infection, the specific properties and relationships between antibodies produced by these B cell compartments are poorly understood. METHODS We utilized a controlled human challenge model of primary dengue virus serotype 2 (DENV2) infection to study acute and convalescent B-cell responses. FINDINGS The level of DENV2 replication was correlated with the magnitude of the plasmablast response. Functional analysis of plasmablast-derived monoclonal antibodies showed that the DENV2-specific response was dominated by cells producing DENV2 serotype-specific antibodies. DENV2-neutralizing antibodies targeted quaternary structure epitopes centered on domain III of the viral envelope protein (EDIII). Functional analysis of MBC and serum antibodies from the same subjects six months post-challenge revealed maintenance of the serotype-specific response in both compartments. The serum response mainly targeted DENV2 serotype-specific epitopes on EDIII. INTERPRETATION Our data suggest overall functional alignment of DENV2-specific responses from the plasmablast, through the MBC and LLPC compartments following primary DENV2 inflection. These results provide enhanced resolution of the temporal and specificity of the B cell compartment in viral infection and serve as framework for evaluation of B cell responses in challenge models. FUNDING This study was supported by the Bill and Melinda Gates Foundation and the National Institutes of Health.
Collapse
Affiliation(s)
- Usha K Nivarthi
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, USA
| | - Huy A Tu
- Department of Microbiology and Molecular Genetics, Vaccine Testing Center, Larner College of Medicine, University of Vermont, Burlington, VT 05405, USA; Cellular, Molecular, and Biomedical Sciences Graduate Program, University of Vermont, Burlington, VT 05405, USA
| | - Matthew J Delacruz
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, USA
| | - Jesica Swanstrom
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, USA
| | - Bhumi Patel
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, USA
| | - Anna P Durbin
- Department of International Health, Center for Immunization Research, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Stephen S Whitehead
- Laboratory of Infectious Diseases, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
| | - Kristen K Pierce
- Department of Microbiology and Molecular Genetics, Vaccine Testing Center, Larner College of Medicine, University of Vermont, Burlington, VT 05405, USA
| | - Beth D Kirkpatrick
- Department of Microbiology and Molecular Genetics, Vaccine Testing Center, Larner College of Medicine, University of Vermont, Burlington, VT 05405, USA
| | - Ralph S Baric
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, USA
| | - Ngan Nguyen
- Atreca, Inc. Redwood City, California 94063, USA
| | | | - Aravinda M de Silva
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, USA.
| | - Sean A Diehl
- Department of Microbiology and Molecular Genetics, Vaccine Testing Center, Larner College of Medicine, University of Vermont, Burlington, VT 05405, USA.
| |
Collapse
|