1
|
Costa-Gouvea TBL, Françoso KS, Marques RF, Gimenez AM, Faria ACM, Cariste LM, Dominguez MR, Vasconcelos JRC, Nakaya HI, Silveira ELV, Soares IS. Poly I:C elicits broader and stronger humoral and cellular responses to a Plasmodium vivax circumsporozoite protein malaria vaccine than Alhydrogel in mice. Front Immunol 2024; 15:1331474. [PMID: 38650939 PMCID: PMC11033515 DOI: 10.3389/fimmu.2024.1331474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 03/18/2024] [Indexed: 04/25/2024] Open
Abstract
Malaria remains a global health challenge, necessitating the development of effective vaccines. The RTS,S vaccination prevents Plasmodium falciparum (Pf) malaria but is ineffective against Plasmodium vivax (Pv) disease. Herein, we evaluated the murine immunogenicity of a recombinant PvCSP incorporating prevalent polymorphisms, adjuvanted with Alhydrogel or Poly I:C. Both formulations induced prolonged IgG responses, with IgG1 dominance by the Alhydrogel group and high titers of all IgG isotypes by the Poly I:C counterpart. Poly I:C-adjuvanted vaccination increased splenic plasma cells, terminally-differentiated memory cells (MBCs), and precursors relative to the Alhydrogel-combined immunization. Splenic B-cells from Poly I:C-vaccinated mice revealed an antibody-secreting cell- and MBC-differentiating gene expression profile. Biological processes such as antibody folding and secretion were highlighted by the Poly I:C-adjuvanted vaccination. These findings underscore the potential of Poly I:C to strengthen immune responses against Pv malaria.
Collapse
Affiliation(s)
- Tiffany B. L. Costa-Gouvea
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Katia S. Françoso
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Rodolfo F. Marques
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Alba Marina Gimenez
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Ana C. M. Faria
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Leonardo M. Cariste
- Laboratório de Vacinas Recombinantes, Departamento de Biociências, Universidade Federal de São Paulo, Santos, Brazil
| | - Mariana R. Dominguez
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - José Ronnie C. Vasconcelos
- Laboratório de Vacinas Recombinantes, Departamento de Biociências, Universidade Federal de São Paulo, Santos, Brazil
| | - Helder I. Nakaya
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
- Institut Pasteur São Paulo, São Paulo, Brazil
- Hospital Israelita Albert Einstein, São Paulo, Brazil
| | - Eduardo L. V. Silveira
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Irene S. Soares
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| |
Collapse
|
2
|
Williams KL, Guerrero S, Flores-Garcia Y, Kim D, Williamson KS, Siska C, Smidt P, Jepson SZ, Li K, Dennison SM, Mathis-Torres S, Chen X, Wille-Reece U, MacGill RS, Walker M, Jongert E, King CR, Ockenhouse C, Glanville J, Moon JE, Regules JA, Tan YC, Cavet G, Lippow SM, Robinson WH, Dutta S, Tomaras GD, Zavala F, Ketchem RR, Emerling DE. A candidate antibody drug for prevention of malaria. Nat Med 2024; 30:117-129. [PMID: 38167935 PMCID: PMC10803262 DOI: 10.1038/s41591-023-02659-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 10/20/2023] [Indexed: 01/05/2024]
Abstract
Over 75% of malaria-attributable deaths occur in children under the age of 5 years. However, the first malaria vaccine recommended by the World Health Organization (WHO) for pediatric use, RTS,S/AS01 (Mosquirix), has modest efficacy. Complementary strategies, including monoclonal antibodies, will be important in efforts to eradicate malaria. Here we characterize the circulating B cell repertoires of 45 RTS,S/AS01 vaccinees and discover monoclonal antibodies for development as potential therapeutics. We generated >28,000 antibody sequences and tested 481 antibodies for binding activity and 125 antibodies for antimalaria activity in vivo. Through these analyses we identified correlations suggesting that sequences in Plasmodium falciparum circumsporozoite protein, the target antigen in RTS,S/AS01, may induce immunodominant antibody responses that limit more protective, but subdominant, responses. Using binding studies, mouse malaria models, biomanufacturing assessments and protein stability assays, we selected AB-000224 and AB-007088 for advancement as a clinical lead and backup. We engineered the variable domains (Fv) of both antibodies to enable low-cost manufacturing at scale for distribution to pediatric populations, in alignment with WHO's preferred product guidelines. The engineered clone with the optimal manufacturing and drug property profile, MAM01, was advanced into clinical development.
Collapse
Affiliation(s)
| | | | - Yevel Flores-Garcia
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Dongkyoon Kim
- Atreca, Inc., San Carlos, CA, USA
- Initium Therapeutics, Inc., Natick, MA, USA
| | | | | | | | | | - Kan Li
- Duke Center for Human Systems Immunology, Department of Surgery, Duke University, Durham, NC, USA
| | - S Moses Dennison
- Duke Center for Human Systems Immunology, Department of Surgery, Duke University, Durham, NC, USA
| | - Shamika Mathis-Torres
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | | | - Ulrike Wille-Reece
- BioNTech US, Inc., Cambridge, MA, USA
- PATH Center for Vaccine Innovation and Access, Washington DC, USA
| | | | | | | | - C Richter King
- PATH Center for Vaccine Innovation and Access, Washington DC, USA
| | | | | | - James E Moon
- Center for Enabling Capabilities, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Jason A Regules
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Yann Chong Tan
- Atreca, Inc., San Carlos, CA, USA
- Nuevocor Pte. Ltd, Singapore, Singapore
| | - Guy Cavet
- Atreca, Inc., San Carlos, CA, USA
- Paramune, Inc., San Carlos, CA, USA
| | | | - William H Robinson
- Division of Immunology and Rheumatology, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Sheetij Dutta
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Georgia D Tomaras
- Duke Center for Human Systems Immunology, Department of Surgery, Duke University, Durham, NC, USA
- Departments of Immunology, Molecular Genetics and Microbiology, Human Vaccine Institute, Duke University, Durham, NC, USA
| | - Fidel Zavala
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | | | | |
Collapse
|
3
|
Geens R, Stanisich J, Beyens O, D'Hondt S, Thiberge J, Ryckebosch A, De Groot A, Magez S, Vertommen D, Amino R, De Winter H, Volkov AN, Tompa P, Sterckx YG. Biophysical characterization of the Plasmodium falciparum circumsporozoite protein's N-terminal domain. Protein Sci 2024; 33:e4852. [PMID: 38059674 PMCID: PMC10749493 DOI: 10.1002/pro.4852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 11/28/2023] [Accepted: 12/04/2023] [Indexed: 12/08/2023]
Abstract
The circumsporozoite protein (CSP) is the main surface antigen of the Plasmodium sporozoite (SPZ) and forms the basis of the currently only licensed anti-malarial vaccine (RTS,S/AS01). CSP uniformly coats the SPZ and plays a pivotal role in its immunobiology, in both the insect and the vertebrate hosts. Although CSP's N-terminal domain (CSPN ) has been reported to play an important role in multiple CSP functions, a thorough biophysical and structural characterization of CSPN is currently lacking. Here, we present an alternative method for the recombinant production and purification of CSPN from Plasmodium falciparum (PfCSPN ), which provides pure, high-quality protein preparations with high yields. Through an interdisciplinary approach combining in-solution experimental methods and in silico analyses, we provide strong evidence that PfCSPN is an intrinsically disordered region displaying some degree of compaction.
Collapse
Affiliation(s)
- Rob Geens
- Laboratory of Medical Biochemistry (LMB)University of AntwerpAntwerpBelgium
- Structural Biology BrusselsVrije Universiteit BrusselBrusselsBelgium
| | - Jessica Stanisich
- Cellular and Molecular ImmunologyVrije Universiteit BrusselBrusselsBelgium
| | - Olivier Beyens
- Laboratory of Medicinal Chemistry (UAMC)University of AntwerpAntwerpBelgium
| | - Stijn D'Hondt
- Laboratory of Medicinal Chemistry (UAMC)University of AntwerpAntwerpBelgium
| | | | - Amber Ryckebosch
- Laboratory of Medical Biochemistry (LMB)University of AntwerpAntwerpBelgium
| | - Anke De Groot
- Laboratory of Medical Biochemistry (LMB)University of AntwerpAntwerpBelgium
| | - Stefan Magez
- Cellular and Molecular ImmunologyVrije Universiteit BrusselBrusselsBelgium
- Ghent University Global CampusIncheonSouth Korea
| | - Didier Vertommen
- de Duve Institute and MASSPROT Platform, UCLouvainBrusselsBelgium
| | - Rogerio Amino
- Unit of Malaria Infection & ImmunityInstitut PasteurParisFrance
| | - Hans De Winter
- Laboratory of Medicinal Chemistry (UAMC)University of AntwerpAntwerpBelgium
| | - Alexander N. Volkov
- Structural Biology BrusselsVrije Universiteit BrusselBrusselsBelgium
- VIB‐VUB Center for Structural BiologyVlaams Instituut voor Biotechnologie (VIB)BrusselsBelgium
- Jean Jeener NMR CentreVrije Universiteit BrusselBrusselsBelgium
| | - Peter Tompa
- Structural Biology BrusselsVrije Universiteit BrusselBrusselsBelgium
- VIB‐VUB Center for Structural BiologyVlaams Instituut voor Biotechnologie (VIB)BrusselsBelgium
- Institute of Enzymology, Biological Research CenterHungarian Academy of SciencesBudapestHungary
| | - Yann G.‐J. Sterckx
- Laboratory of Medical Biochemistry (LMB)University of AntwerpAntwerpBelgium
| |
Collapse
|
4
|
Vigdorovich V, Patel H, Watson A, Raappana A, Reynolds L, Selman W, Beeman S, Edlefsen PT, Kappe SHI, Sather DN. Coimmunization with Preerythrocytic Antigens alongside Circumsporozoite Protein Can Enhance Sterile Protection against Plasmodium Sporozoite Infection. Microbiol Spectr 2023; 11:e0379122. [PMID: 36847573 PMCID: PMC10100930 DOI: 10.1128/spectrum.03791-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 02/10/2023] [Indexed: 03/01/2023] Open
Abstract
Malaria-causing Plasmodium parasites have a complex life cycle and present numerous antigen targets that may contribute to protective immune responses. The currently recommended vaccine-RTS,S-functions by targeting the Plasmodium falciparum circumsporozoite protein (CSP), which is the most abundant surface protein of the sporozoite form responsible for initiating infection of the human host. Despite showing only moderate efficacy, RTS,S has established a strong foundation for the development of next-generation subunit vaccines. Our previous work characterizing the sporozoite surface proteome identified additional non-CSP antigens that may be useful as immunogens individually or in combination with CSP. In this study, we examined eight such antigens using the rodent malaria parasite Plasmodium yoelii as a model system. We demonstrate that despite conferring weak protection individually, coimmunizing each of several of these antigens alongside CSP could significantly enhance the sterile protection achieved by CSP immunization alone. Thus, our work provides compelling evidence that a multiantigen preerythrocytic vaccine approach may enhance protection compared to CSP-only vaccines. This lays the groundwork for further studies aimed at testing the identified antigen combinations in human vaccination trials that assess efficacy with controlled human malaria infection. IMPORTANCE The currently approved malaria vaccine targets a single parasite protein (CSP) and results in only partial protection. We tested several additional vaccine targets in combination with CSP to identify those that could enhance protection from infection upon challenge in the mouse malaria model. In identifying several such enhancing vaccine targets, our work indicates that a multiprotein immunization approach may be a promising avenue to achieving higher levels of protection from infection. Our work identified several candidate leads for follow-up in the models relevant for human malaria and provides an experimental framework for efficiently carrying out such screens for other combinations of vaccine targets.
Collapse
Affiliation(s)
- Vladimir Vigdorovich
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, Washington, USA
| | - Hardik Patel
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, Washington, USA
| | - Alexander Watson
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, Washington, USA
| | - Andrew Raappana
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, Washington, USA
| | - Laura Reynolds
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, Washington, USA
| | - William Selman
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, Washington, USA
| | - Suzannah Beeman
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, Washington, USA
| | - Paul T. Edlefsen
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Stefan H. I. Kappe
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, Washington, USA
- Department of Pediatrics, University of Washington, Seattle, Washington, USA
- Department of Global Health, University of Washington, Seattle, Washington, USA
| | - D. Noah Sather
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, Washington, USA
- Department of Pediatrics, University of Washington, Seattle, Washington, USA
- Department of Global Health, University of Washington, Seattle, Washington, USA
| |
Collapse
|
5
|
Tumwine-Downey I, Deroost K, Levy P, McLaughlin S, Hosking C, Langhorne J. Antibody-dependent immune responses elicited by blood stage-malaria infection contribute to protective immunity to the pre-erythrocytic stages. Curr Res Immunol 2022; 4:100054. [PMID: 36593995 PMCID: PMC9803926 DOI: 10.1016/j.crimmu.2022.100054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 11/21/2022] [Accepted: 12/13/2022] [Indexed: 12/24/2022] Open
Abstract
Advances in transcriptomics and proteomics have revealed that different life-cycle stages of the malaria parasite, Plasmodium, share antigens, thus allowing for the possibility of eliciting immunity to a parasite life-cycle stage that has not been experienced before. Using the Plasmodium chabaudi (AS strain) model of malaria in mice, we investigated how isolated exposure to blood-stage infection, bypassing a liver-stage infection, yields significant protection to sporozoite challenge resulting in lower liver parasite burdens. Antibodies are the main immune driver of this protection. Antibodies induced by blood-stage infection recognise proteins on the surface of sporozoites and can impair sporozoite gliding motility in vitro, suggesting a possible function in vivo. Furthermore, mice lacking B cells and/or secreted antibodies are not protected against a sporozoite challenge in mice that had a previous blood-stage infection. Conversely, effector CD4+ and CD8+ T cells do not seem to play a role in protection from sporozoite challenge of mice previously exposed only to the blood stages of P. chabaudi. The protective response against pre-erythrocytic stages can be induced by infections initiated by serially passaged blood-stage parasites as well as recently mosquito transmitted parasites and is effective against a different strain of P. chabaudi (CB strain), but not against another rodent malaria species, P. yoelii. The possibility to induce protective cross-stage antibodies advocates the need to consider both stage-specific and cross-stage immune responses to malaria, as natural infection elicits exposure to all life-cycle stages. Future investigation into these cross-stage antibodies allows the opportunity for candidate antigens to contribute to malaria vaccine development.
Collapse
Affiliation(s)
| | | | | | | | | | - Jean Langhorne
- Corresponding author. Malaria Immunology Laboratory, Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK.
| |
Collapse
|
6
|
Tashi T, Upadhye A, Kundu P, Wu C, Menant S, Soares RR, Ferreira MU, Longley RJ, Mueller I, Hoang QQ, Tham WH, Rayner JC, Scopel KKG, Lima-Junior JC, Tran TM. Longitudinal IgG antibody responses to Plasmodium vivax blood-stage antigens during and after acute vivax malaria in individuals living in the Brazilian Amazon. PLoS Negl Trop Dis 2022; 16:e0010773. [PMID: 36417454 PMCID: PMC9728838 DOI: 10.1371/journal.pntd.0010773] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 12/07/2022] [Accepted: 11/11/2022] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND To make progress towards malaria elimination, a highly effective vaccine targeting Plasmodium vivax is urgently needed. Evaluating the kinetics of natural antibody responses to vaccine candidate antigens after acute vivax malaria can inform the design of serological markers of exposure and vaccines. METHODOLOGY/PRINCIPAL FINDINGS The responses of IgG antibodies to 9 P. vivax vaccine candidate antigens were evaluated in longitudinal serum samples from Brazilian individuals collected at the time of acute vivax malaria and 30, 60, and 180 days afterwards. Antigen-specific IgG correlations, seroprevalence, and half-lives were determined for each antigen using the longitudinal data. Antibody reactivities against Pv41 and PVX_081550 strongly correlated with each other at each of the four time points. The analysis identified robust responses in terms of magnitude and seroprevalence against Pv41 and PvGAMA at 30 and 60 days. Among the 8 P. vivax antigens demonstrating >50% seropositivity across all individuals, antibodies specific to PVX_081550 had the longest half-life (100 days; 95% CI, 83-130 days), followed by PvRBP2b (91 days; 95% CI, 76-110 days) and Pv12 (82 days; 95% CI, 64-110 days). CONCLUSION/SIGNIFICANCE This study provides an in-depth assessment of the kinetics of antibody responses to key vaccine candidate antigens in Brazilians with acute vivax malaria. Follow-up studies are needed to determine whether the longer-lived antibody responses induced by natural infection are effective in controlling blood-stage infection and mediating clinical protection.
Collapse
Affiliation(s)
- Tenzin Tashi
- Division of Infectious Diseases, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Department of Microbiology and Immunology, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Aditi Upadhye
- Division of Infectious Diseases, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Prasun Kundu
- Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, United Kingdom
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, United Kingdom
| | - Chunxiang Wu
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Sébastien Menant
- Infectious Diseases and Immune Defence Division, Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
| | - Roberta Reis Soares
- Department of Parasitology, Microbiology and Immunology, Institute of Biological Sciences, Federal University of Juiz de Fora, Juiz de Fora, Brazil
| | - Marcelo U. Ferreira
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
- Global Health and Tropical Medicine, Institute of Hygiene and Tropical Medicine, Nova University of Lisbon, Lisbon, Portugal
| | - Rhea J. Longley
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Victoria, Australia
| | - Ivo Mueller
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Victoria, Australia
| | - Quyen Q. Hoang
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Wai-Hong Tham
- Infectious Diseases and Immune Defence Division, Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Victoria, Australia
| | - Julian C. Rayner
- Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, United Kingdom
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, United Kingdom
| | - Kézia KG Scopel
- Department of Parasitology, Microbiology and Immunology, Institute of Biological Sciences, Federal University of Juiz de Fora, Juiz de Fora, Brazil
| | - Josué C. Lima-Junior
- Laboratory of Immunoparasitology, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro, Brazil
| | - Tuan M. Tran
- Division of Infectious Diseases, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Department of Microbiology and Immunology, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Ryan White Center for Pediatric Infectious Diseases and Global Health, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- * E-mail:
| |
Collapse
|
7
|
Tas JMJ, Koo JH, Lin YC, Xie Z, Steichen JM, Jackson AM, Hauser BM, Wang X, Cottrell CA, Torres JL, Warner JE, Kirsch KH, Weldon SR, Groschel B, Nogal B, Ozorowski G, Bangaru S, Phelps N, Adachi Y, Eskandarzadeh S, Kubitz M, Burton DR, Lingwood D, Schmidt AG, Nair U, Ward AB, Schief WR, Batista FD. Antibodies from primary humoral responses modulate the recruitment of naive B cells during secondary responses. Immunity 2022; 55:1856-1871.e6. [PMID: 35987201 PMCID: PMC9350677 DOI: 10.1016/j.immuni.2022.07.020] [Citation(s) in RCA: 48] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 07/15/2022] [Accepted: 07/27/2022] [Indexed: 01/19/2023]
Abstract
Vaccines generate high-affinity antibodies by recruiting antigen-specific B cells to germinal centers (GCs), but the mechanisms governing the recruitment to GCs on secondary challenges remain unclear. Here, using preclinical SARS-CoV and HIV mouse models, we demonstrated that the antibodies elicited during primary humoral responses shaped the naive B cell recruitment to GCs during secondary exposures. The antibodies from primary responses could either enhance or, conversely, restrict the GC participation of naive B cells: broad-binding, low-affinity, and low-titer antibodies enhanced recruitment, whereas, by contrast, the high titers of high-affinity, mono-epitope-specific antibodies attenuated cognate naive B cell recruitment. Thus, the directionality and intensity of that effect was determined by antibody concentration, affinity, and epitope specificity. Circulating antibodies can, therefore, be important determinants of antigen immunogenicity. Future vaccines may need to overcome-or could, alternatively, leverage-the effects of circulating primary antibodies on subsequent naive B cell recruitment.
Collapse
Affiliation(s)
- Jeroen M J Tas
- The Ragon Institute of MGH, MIT, and Harvard University, Cambridge, MA 02139, USA
| | - Ja-Hyun Koo
- The Ragon Institute of MGH, MIT, and Harvard University, Cambridge, MA 02139, USA
| | - Ying-Cing Lin
- The Ragon Institute of MGH, MIT, and Harvard University, Cambridge, MA 02139, USA
| | - Zhenfei Xie
- The Ragon Institute of MGH, MIT, and Harvard University, Cambridge, MA 02139, USA
| | - Jon M Steichen
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; Center for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA
| | - Abigail M Jackson
- IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; Department of Integrative, Structural and Computational Biology, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA
| | - Blake M Hauser
- The Ragon Institute of MGH, MIT, and Harvard University, Cambridge, MA 02139, USA
| | - Xuesong Wang
- The Ragon Institute of MGH, MIT, and Harvard University, Cambridge, MA 02139, USA
| | - Christopher A Cottrell
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; Center for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA
| | - Jonathan L Torres
- IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; Center for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; Department of Integrative, Structural and Computational Biology, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA
| | - John E Warner
- The Ragon Institute of MGH, MIT, and Harvard University, Cambridge, MA 02139, USA
| | - Kathrin H Kirsch
- The Ragon Institute of MGH, MIT, and Harvard University, Cambridge, MA 02139, USA
| | - Stephanie R Weldon
- The Ragon Institute of MGH, MIT, and Harvard University, Cambridge, MA 02139, USA
| | - Bettina Groschel
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; Center for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA
| | - Bartek Nogal
- IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; Center for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; Department of Integrative, Structural and Computational Biology, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA
| | - Gabriel Ozorowski
- Department of Integrative, Structural and Computational Biology, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA
| | - Sandhya Bangaru
- IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; Center for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; Department of Integrative, Structural and Computational Biology, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA
| | - Nicole Phelps
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; Center for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA
| | - Yumiko Adachi
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; Center for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA
| | - Saman Eskandarzadeh
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; Center for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA
| | - Michael Kubitz
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; Center for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA
| | - Dennis R Burton
- The Ragon Institute of MGH, MIT, and Harvard University, Cambridge, MA 02139, USA; Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; Center for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA
| | - Daniel Lingwood
- The Ragon Institute of MGH, MIT, and Harvard University, Cambridge, MA 02139, USA
| | - Aaron G Schmidt
- The Ragon Institute of MGH, MIT, and Harvard University, Cambridge, MA 02139, USA; Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA
| | - Usha Nair
- The Ragon Institute of MGH, MIT, and Harvard University, Cambridge, MA 02139, USA
| | - Andrew B Ward
- IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; Center for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; Department of Integrative, Structural and Computational Biology, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA
| | - William R Schief
- The Ragon Institute of MGH, MIT, and Harvard University, Cambridge, MA 02139, USA; Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA; Center for HIV/AIDS Vaccine Development, The Scripps Research Institute, La Jolla, San Diego, CA 92037, USA
| | - Facundo D Batista
- The Ragon Institute of MGH, MIT, and Harvard University, Cambridge, MA 02139, USA; Department of Immunology, Harvard Medical School, Boston, MA 02115, USA; Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA.
| |
Collapse
|
8
|
Visweswaran GRR, Vijayan K, Chandrasekaran R, Trakhimets O, Brown SL, Vigdorovich V, Yang A, Raappana A, Watson A, Selman W, Zuck M, Dambrauskas N, Kaushansky A, Sather DN. Germinal center activity and B cell maturation are associated with protective antibody responses against Plasmodium pre-erythrocytic infection. PLoS Pathog 2022; 18:e1010671. [PMID: 35793394 PMCID: PMC9292112 DOI: 10.1371/journal.ppat.1010671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 07/18/2022] [Accepted: 06/13/2022] [Indexed: 11/19/2022] Open
Abstract
Blocking Plasmodium, the causative agent of malaria, at the asymptomatic pre-erythrocytic stage would abrogate disease pathology and prevent transmission. However, the lack of well-defined features within vaccine-elicited antibody responses that correlate with protection represents a major roadblock to improving on current generation vaccines. We vaccinated mice (BALB/cJ and C57BL/6J) with Py circumsporozoite protein (CSP), the major surface antigen on the sporozoite, and evaluated vaccine-elicited humoral immunity and identified immunological factors associated with protection after mosquito bite challenge. Vaccination achieved 60% sterile protection and otherwise delayed blood stage patency in BALB/cJ mice. In contrast, all C57BL/6J mice were infected similar to controls. Protection was mediated by antibodies and could be passively transferred from immunized BALB/cJ mice into naïve C57BL/6J. Dissection of the underlying immunological features of protection revealed early deficits in antibody titers and polyclonal avidity in C57BL/6J mice. Additionally, PyCSP-vaccination in BALB/cJ induced a significantly higher proportion of antigen-specific B-cells and class-switched memory B-cell (MBCs) populations than in C57BL/6J mice. Strikingly, C57BL/6J mice also had markedly fewer CSP-specific germinal center experienced B cells and class-switched MBCs compared to BALB/cJ mice. Analysis of the IgG γ chain repertoires by next generation sequencing in PyCSP-specific memory B-cell repertoires also revealed higher somatic hypermutation rates in BALB/cJ mice than in C57BL/6J mice. These findings indicate that the development of protective antibody responses in BALB/cJ mice in response to vaccination with PyCSP was associated with increased germinal center activity and somatic mutation compared to C57BL/6J mice, highlighting the key role B cell maturation may have in the development of vaccine-elicited protective antibodies against CSP. Identifying specific features of vaccine-elicited antibody responses that are associated with protection from malaria infection is a key step toward the development of a safe and effective vaccine. Here we compared antibody and B cell responses in two mouse strains that exhibited a differential ability to generate antibodies that protect from infection challenge. We found that protection was due to the presence of vaccine-elicited antibodies and could be transferred between strains, and that the ability of antibodies to neutralize the parasite was directly linked to the strength (affinity) with which it binds CSP. Thus, we sought to understand if there were differences in the two strains in the process of B cell maturation that leads to generation of high affinity, protective antibody responses after vaccination. Overall, our comparative analysis indicates that germinal center (GC) activity, a key process in B cell maturation, was significantly diminished in the non-protected strain. Further, we observed evidence of higher levels of somatic mutation, which is a result of germinal center activity, in protected mice. Thus, our results indicate that the ability to generate protective antibody responses was linked to enhanced B cell maturation in the protected strain, providing a key clue to the type of responses that should be generated by future vaccines.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Ashton Yang
- Seattle Children’s Research Institute, Seattle, Washington
| | | | - Alex Watson
- Seattle Children’s Research Institute, Seattle, Washington
| | - William Selman
- Seattle Children’s Research Institute, Seattle, Washington
| | - Meghan Zuck
- Seattle Children’s Research Institute, Seattle, Washington
| | | | - Alexis Kaushansky
- Seattle Children’s Research Institute, Seattle, Washington
- Department of Pediatrics, University of Washington, Seattle, Washington
- Department of Global Health, University of Washington, Seattle, Washington
- Brotman Baty Research Institute, Seattle, Washington
- Institute for Stem Cell and Regenerative Medicine, Seattle, Washington
- * E-mail: (AK); (DNS)
| | - D. Noah Sather
- Seattle Children’s Research Institute, Seattle, Washington
- Department of Pediatrics, University of Washington, Seattle, Washington
- Department of Global Health, University of Washington, Seattle, Washington
- * E-mail: (AK); (DNS)
| |
Collapse
|
9
|
Wilder BK, Vigdorovich V, Carbonetti S, Minkah N, Hertoghs N, Raappana A, Cardamone H, Oliver BG, Trakhimets O, Kumar S, Dambrauskas N, Arredondo SA, Camargo N, Seilie AM, Murphy SC, Kappe SHI, Sather DN. Anti-TRAP/SSP2 monoclonal antibodies can inhibit sporozoite infection and may enhance protection of anti-CSP monoclonal antibodies. NPJ Vaccines 2022; 7:58. [PMID: 35618791 PMCID: PMC9135708 DOI: 10.1038/s41541-022-00480-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 04/22/2022] [Indexed: 11/10/2022] Open
Abstract
Vaccine-induced sterilizing protection from infection by Plasmodium parasites, the pathogens that cause malaria, will be essential in the fight against malaria as it would prevent both malaria-related disease and transmission. Stopping the relatively small number of parasites injected by the mosquito before they can migrate from the skin to the liver is an attractive means to this goal. Antibody-eliciting vaccines have been used to pursue this objective by targeting the major parasite surface protein present during this stage, the circumsporozoite protein (CSP). While CSP-based vaccines have recently had encouraging success in disease reduction, this was only achieved with extremely high antibody titers and appeared less effective for a complete block of infection (i.e., sterile protection). While such disease reduction is important, these and other results indicate that strategies focusing on CSP alone may not achieve the high levels of sterile protection needed for malaria eradication. Here, we show that monoclonal antibodies (mAbs) recognizing another sporozoite protein, TRAP/SSP2, exhibit a range of inhibitory activity and that these mAbs may augment CSP-based protection despite conferring no sterile protection on their own. Therefore, pursuing a multivalent subunit vaccine immunization is a promising strategy for improving infection-blocking malaria vaccines.
Collapse
Affiliation(s)
- Brandon K Wilder
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, USA.,Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR, 97006, USA
| | - Vladimir Vigdorovich
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, USA
| | - Sara Carbonetti
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, USA
| | - Nana Minkah
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, USA
| | - Nina Hertoghs
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, USA
| | - Andrew Raappana
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, USA
| | - Hayley Cardamone
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, USA
| | - Brian G Oliver
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, USA
| | - Olesya Trakhimets
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, USA
| | - Sudhir Kumar
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, USA
| | - Nicholas Dambrauskas
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, USA
| | - Silvia A Arredondo
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, USA
| | - Nelly Camargo
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, USA
| | - Annette M Seilie
- Department of Laboratory Medicine and Pathology and Center for Emerging and Re-emerging Infectious Diseases, University of Washington, Seattle, WA, USA
| | - Sean C Murphy
- Department of Laboratory Medicine and Pathology and Center for Emerging and Re-emerging Infectious Diseases, University of Washington, Seattle, WA, USA.,Department of Microbiology, University of Washington, Seattle, WA, USA
| | - Stefan H I Kappe
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, USA. .,Department of Pediatrics, University of Washington, Seattle, WA, USA. .,Department of Global Health, University of Washington, Seattle, WA, USA.
| | - D Noah Sather
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, USA. .,Department of Pediatrics, University of Washington, Seattle, WA, USA. .,Department of Global Health, University of Washington, Seattle, WA, USA.
| |
Collapse
|
10
|
Tsai CM, Hajam IA, Caldera JR, Liu GY. Integrating complex host-pathogen immune environments into S. aureus vaccine studies. Cell Chem Biol 2022; 29:730-740. [PMID: 35594849 DOI: 10.1016/j.chembiol.2022.04.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 02/16/2022] [Accepted: 04/14/2022] [Indexed: 11/18/2022]
Abstract
Staphylococcus aureus (SA) is a leading cause of bacterial infection and antibiotic resistance globally. Therefore, development of an effective vaccine has been a major goal of the SA field for the past decades. With the wealth of understanding of pathogenesis, the failure of all SA vaccine trials has been a surprise. We argue that experimental SA vaccines have not worked because vaccines have been studied in naive laboratory animals, whereas clinical vaccine efficacy is tested in immune environments reprogrammed by SA. Here, we review the failed SA vaccines that have seemingly defied all principles of vaccinology. We describe major SA evasion strategies and suggest that they reshape the immune environment in a way that makes vaccines prone to failures. We propose that appropriate integration of concepts of host-pathogen interaction into vaccine study designs could lead to insight critical for the development of an effective SA vaccine.
Collapse
Affiliation(s)
- Chih-Ming Tsai
- Division of Infectious Diseases, Department of Pediatrics, University of California San Diego, La Jolla, CA 92093, USA
| | - Irshad A Hajam
- Division of Infectious Diseases, Department of Pediatrics, University of California San Diego, La Jolla, CA 92093, USA
| | - J R Caldera
- Division of Infectious Diseases, Department of Pediatrics, University of California San Diego, La Jolla, CA 92093, USA; Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - George Y Liu
- Division of Infectious Diseases, Department of Pediatrics, University of California San Diego, La Jolla, CA 92093, USA; Division of Infectious Diseases, Rady Children's Hospital, San Diego, CA 92123, USA.
| |
Collapse
|
11
|
Langowski MD, Khan FA, Savransky S, Brown DR, Balasubramaniyam A, Harrison WB, Zou X, Beck Z, Matyas GR, Regules JA, Miller R, Soisson LA, Batchelor AH, Dutta S. Restricted valency (NPNA) n repeats and junctional epitope-based circumsporozoite protein vaccines against Plasmodium falciparum. NPJ Vaccines 2022; 7:13. [PMID: 35087099 PMCID: PMC8795123 DOI: 10.1038/s41541-022-00430-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 12/14/2021] [Indexed: 12/02/2022] Open
Abstract
The Circumsporozoite Protein (CSP) of Plasmodium falciparum contains an N-terminal region, a conserved Region I (RI), a junctional region, 25-42 copies of major (NPNA) and minor repeats followed by a C-terminal domain. The recently approved malaria vaccine, RTS,S/AS01 contains NPNAx19 and the C-terminal region of CSP. The efficacy of RTS,S against natural infection is low and short-lived, and mapping epitopes of inhibitory monoclonal antibodies may allow for rational improvement of CSP vaccines. Tobacco Mosaic Virus (TMV) was used here to display the junctional epitope (mAb CIS43), Region I (mAb 5D5), NPNAx5, and NPNAx20 epitope of CSP (mAbs 317 and 580). Protection studies in mice revealed that Region I did not elicit protective antibodies, and polyclonal antibodies against the junctional epitope showed equivalent protection to NPNAx5. Combining the junctional and NPNAx5 epitopes reduced immunogenicity and efficacy, and increasing the repeat valency to NPNAx20 did not improve upon NPNAx5. TMV was confirmed as a versatile vaccine platform for displaying small epitopes defined by neutralizing mAbs. We show that polyclonal antibodies against engineered VLPs can recapitulate the binding specificity of the mAbs and immune-focusing by reducing the structural complexity of an epitope may be superior to immune-broadening as a vaccine design approach. Most importantly the junctional and restricted valency NPNA epitopes can be the basis for developing highly effective second-generation malaria vaccine candidates.
Collapse
Affiliation(s)
- Mark D Langowski
- Structural Vaccinology Lab, Malaria Biologics Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Farhat A Khan
- Structural Vaccinology Lab, Malaria Biologics Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Sofya Savransky
- Structural Vaccinology Lab, Malaria Biologics Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Dallas R Brown
- Structural Vaccinology Lab, Malaria Biologics Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Arasu Balasubramaniyam
- Structural Vaccinology Lab, Malaria Biologics Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - William B Harrison
- Structural Vaccinology Lab, Malaria Biologics Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Xiaoyan Zou
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, USA
| | - Zoltan Beck
- US Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, USA
- Pfizer, 401N Middletown Rd, Pearl River, NY, 10965, USA
| | - Gary R Matyas
- US Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Jason A Regules
- Malaria Biologics Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Robin Miller
- United States Agency for International Development, Washington, DC, USA
| | | | - Adrian H Batchelor
- Structural Vaccinology Lab, Malaria Biologics Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Sheetij Dutta
- Structural Vaccinology Lab, Malaria Biologics Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA.
| |
Collapse
|