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Healer J, Thompson JK, Mackwell KL, Browne CD, Seager BA, Ngo A, Lowes KN, Silk SE, Pulido D, King LDW, Christen JM, Noe AR, Kotraiah V, Masendycz PJ, Rajagopalan R, Lucas L, Stanford MM, Soisson L, Diggs C, Miller R, Youll S, Wycherley K, Draper SJ, Cowman AF. RH5.1-CyRPA-Ripr antigen combination vaccine shows little improvement over RH5.1 in a preclinical setting. Front Cell Infect Microbiol 2022; 12:1049065. [PMID: 36605129 PMCID: PMC9807911 DOI: 10.3389/fcimb.2022.1049065] [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] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Accepted: 12/05/2022] [Indexed: 12/24/2022] Open
Abstract
Background RH5 is the leading vaccine candidate for the Plasmodium falciparum blood stage and has shown impact on parasite growth in the blood in a human clinical trial. RH5 binds to Ripr and CyRPA at the apical end of the invasive merozoite form, and this complex, designated RCR, is essential for entry into human erythrocytes. RH5 has advanced to human clinical trials, and the impact on parasite growth in the blood was encouraging but modest. This study assessed the potential of a protein-in-adjuvant blood stage malaria vaccine based on a combination of RH5, Ripr and CyRPA to provide improved neutralizing activity against P. falciparum in vitro. Methods Mice were immunized with the individual RCR antigens to down select the best performing adjuvant formulation and rats were immunized with the individual RCR antigens to select the correct antigen dose. A second cohort of rats were immunized with single, double and triple antigen combinations to assess immunogenicity and parasite neutralizing activity in growth inhibition assays. Results The DPX® platform was identified as the best performing formulation in potentiating P. falciparum inhibitory antibody responses to these antigens. The three antigens derived from RH5, Ripr and CyRPA proteins formulated with DPX induced highly inhibitory parasite neutralising antibodies. Notably, RH5 either as a single antigen or in combination with Ripr and/or CyRPA, induced inhibitory antibodies that outperformed CyRPA, Ripr. Conclusion An RCR combination vaccine may not induce substantially improved protective immunity as compared with RH5 as a single immunogen in a clinical setting and leaves the development pathway open for other antigens to be combined with RH5 as a next generation malaria vaccine.
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Affiliation(s)
- Julie Healer
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia,University of Melbourne, Melbourne, VIC, Australia
| | - Jennifer K. Thompson
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
| | - Karen L. Mackwell
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
| | | | - Benjamin A. Seager
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia,University of Melbourne, Melbourne, VIC, Australia
| | - Anna Ngo
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
| | - Kym N. Lowes
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia,University of Melbourne, Melbourne, VIC, Australia
| | - Sarah E. Silk
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - David Pulido
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Lloyd D. W. King
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | | | - Amy R. Noe
- Leidos Life Sciences, Frederick, MD, United States
| | | | - Paul J. Masendycz
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
| | | | | | | | - Lorraine Soisson
- Malaria Vaccine Development Program, United States Agency for International Development (USAID), Washington, DC, United States
| | - Carter Diggs
- Malaria Vaccine Development Program, United States Agency for International Development (USAID), Washington, DC, United States
| | - Robin Miller
- Malaria Vaccine Development Program, United States Agency for International Development (USAID), Washington, DC, United States
| | - Susan Youll
- Malaria Vaccine Development Program, United States Agency for International Development (USAID), Washington, DC, United States
| | - Kaye Wycherley
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
| | - Simon J. Draper
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Alan F. Cowman
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia,University of Melbourne, Melbourne, VIC, Australia,*Correspondence: Alan F. Cowman,
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2
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Berry AA, Gottlieb ER, Kouriba B, Diarra I, Thera MA, Dutta S, Coulibaly D, Ouattara A, Niangaly A, Kone AK, Traore K, Tolo Y, Mishcherkin V, Soisson L, Diggs CL, Blackwelder WC, Laurens MB, Sztein MB, Doumbo OK, Plowe CV, Lyke KE. Immunoglobulin G subclass and antibody avidity responses in Malian children immunized with Plasmodium falciparum apical membrane antigen 1 vaccine candidate FMP2.1/AS02 A. Malar J 2019; 18:13. [PMID: 30658710 PMCID: PMC6339315 DOI: 10.1186/s12936-019-2637-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Accepted: 01/08/2019] [Indexed: 11/10/2022] Open
Abstract
Background A malaria vaccine based on Plasmodium falciparum apical membrane antigen 1 (AMA1) elicited strain specific efficacy in Malian children that waned in the second season after vaccination despite sustained AMA1 antibody titers. With the goal of identifying a humoral correlate of vaccine-induced protection, pre- and post-vaccination sera from children vaccinated with the AMA1 vaccine and from a control group that received a rabies vaccine were tested for AMA1-specific immunoglobulin G (IgG) subclasses (IgG1, IgG2, IgG3, and IgG4) and for antibody avidity. Methods Samples from a previously completed Phase 2 AMA1 vaccine trial in children residing in Mali, West Africa were used to determine AMA1-specific IgG subclass antibody titers and avidity by ELISA. Cox proportional hazards models were used to assess correlation between IgG subclass antibody titers and risk of time to first or only clinical malaria episode and risk of multiple episodes. Asexual P. falciparum parasite density measured for each child as area under the curve were used to assess correlation between IgG subclass antibody titers and parasite burden. Results AMA1 vaccination did not elicit a change in antibody avidity; however, AMA1 vaccinees had a robust IgG subclass response that persisted over the malaria transmission season. AMA1-specific IgG subclass responses were not associated with decreased risk of subsequent clinical malaria. For the AMA1 vaccine group, IgG3 levels at study day 90 correlated with high parasite burden during days 90–240. In the control group, AMA1-specific IgG subclass rise and persistence over the malaria season was modest and correlated with age. In the control group, titers of several IgG subclasses at days 90 and 240 correlated with parasite burden over the first 90 study days, and IgG3 at day 240 correlated with parasite burden during days 90–240. Conclusions Neither IgG subclass nor avidity was associated with the modest, strain-specific efficacy elicited by this blood stage malaria vaccine. Although a correlate of protection was not identified, correlations between subclass titers and age, and correlations between IgG subclass titers and parasite burden, defined by area under the curve parasitaemia levels, were observed, which expand knowledge about IgG subclass responses. IgG3, known to have the shortest half-life of the IgG subclasses, might be the most temporally relevant indicator of ongoing malaria exposure when examining antibody responses to AMA1. Electronic supplementary material The online version of this article (10.1186/s12936-019-2637-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Andrea A Berry
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA.
| | - Eric R Gottlieb
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA.,Warren Alpert Medical School, Brown University, Providence, RI, USA
| | - Bourema Kouriba
- University of Sciences, Techniques, and Technologies, Bamako, Bamako, Mali
| | - Issa Diarra
- University of Sciences, Techniques, and Technologies, Bamako, Bamako, Mali
| | - Mahamadou A Thera
- University of Sciences, Techniques, and Technologies, Bamako, Bamako, Mali
| | - Sheetij Dutta
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Drissa Coulibaly
- University of Sciences, Techniques, and Technologies, Bamako, Bamako, Mali
| | - Amed Ouattara
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Amadou Niangaly
- University of Sciences, Techniques, and Technologies, Bamako, Bamako, Mali
| | - Abdoulaye K Kone
- University of Sciences, Techniques, and Technologies, Bamako, Bamako, Mali
| | - Karim Traore
- University of Sciences, Techniques, and Technologies, Bamako, Bamako, Mali
| | - Youssouf Tolo
- University of Sciences, Techniques, and Technologies, Bamako, Bamako, Mali
| | - Vladimir Mishcherkin
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Lorraine Soisson
- United States Agency for International Development, Washington, DC, USA
| | - Carter L Diggs
- United States Agency for International Development, Washington, DC, USA
| | - William C Blackwelder
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Matthew B Laurens
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Marcelo B Sztein
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Ogobara K Doumbo
- University of Sciences, Techniques, and Technologies, Bamako, Bamako, Mali
| | - Christopher V Plowe
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA.,Duke Global Health Institute, Duke University, 310 Trent Drive, Durham, NC, USA
| | - Kirsten E Lyke
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
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3
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Srinivasan P, Baldeviano GC, Miura K, Diouf A, Ventocilla JA, Leiva KP, Lugo-Roman L, Lucas C, Orr-Gonzalez S, Zhu D, Villasante E, Soisson L, Narum DL, Pierce SK, Long CA, Diggs C, Duffy PE, Lescano AG, Miller LH. A malaria vaccine protects Aotus monkeys against virulent Plasmodium falciparum infection. NPJ Vaccines 2017; 2. [PMID: 28804644 PMCID: PMC5551459 DOI: 10.1038/s41541-017-0015-7] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [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] [Indexed: 11/24/2022] Open
Abstract
The Plasmodium falciparum protein, apical membrane antigen 1 forms a complex with another parasite protein, rhoptry neck protein 2, to initiate junction formation with the erythrocyte and is essential for merozoite invasion during the blood stage of infection. Consequently, apical membrane antigen 1 has been a target of vaccine development but vaccination with apical membrane antigen 1 alone in controlled human malaria infections failed to protect and showed limited efficacy in field trials. Here we show that vaccination with AMA1–RON2L complex in Freund’s adjuvant protects Aotus monkeys against a virulent Plasmodium falciparum infection. Vaccination with AMA1 alone gave only partial protection, delaying infection in one of eight animals. However, the AMA1–RON2L complex vaccine completely protected four of eight monkeys and substantially delayed infection (>25 days) in three of the other four animals. Interestingly, antibodies from monkeys vaccinated with the AMA1–RON2L complex had significantly higher neutralizing activity than antibodies from monkeys vaccinated with AMA1 alone. Importantly, we show that antibodies from animals vaccinated with the complex have significantly higher neutralization activity against non-vaccine type parasites. We suggest that vaccination with the AMA1–RON2L complex induces functional antibodies that better recognize AMA1 as it appears complexed with RON2 during merozoite invasion. These data justify progression of this next generation AMA1 vaccine towards human trials. A vaccine targeting a protein complex that allows malaria-causing parasite to enter red blood cells has been produced. Malaria caused by the parasite Plasmodium falciparum is an oft-deadly infectious disease without an effective vaccine. A team of researchers at the National Institutes of Health led by Prakash Srinivasan, currently at the Johns Hopkins Malaria Research Institute, United States, demonstrated the efficacy of a vaccine candidate that works by priming a host’s immune system to a parasitic protein complex required to form a junction with red blood cells, allowing entry and proliferation of the pathogen. The group’s vaccine conferred more effective protection in monkeys than prior candidates that targeted only one component of the parasitic protein complex. This research warrants a closer look into how this candidate, and others targeting the protein complex, can be used to prevent malaria in humans.
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Affiliation(s)
- Prakash Srinivasan
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | | | - Kazutoyo Miura
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Ababacar Diouf
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | | | - Karina P Leiva
- US Naval Medical Research Unit No. 6 (NAMRU-6), Callao, Peru
| | - Luis Lugo-Roman
- US Naval Medical Research Unit No. 6 (NAMRU-6), Callao, Peru
| | - Carmen Lucas
- US Naval Medical Research Unit No. 6 (NAMRU-6), Callao, Peru
| | - Sachy Orr-Gonzalez
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Daming Zhu
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Eileen Villasante
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD, USA
| | - Lorraine Soisson
- Malaria Vaccine Development Program, U.S. Agency for International Development, Washington, DC, USA
| | - David L Narum
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Susan K Pierce
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Carole A Long
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Carter Diggs
- Malaria Vaccine Development Program, U.S. Agency for International Development, Washington, DC, USA
| | - Patrick E Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | | | - Louis H Miller
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
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4
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Sedegah M, Peters B, Hollingdale MR, Ganeshan HD, Huang J, Farooq F, Belmonte MN, Belmonte AD, Limbach KJ, Diggs C, Soisson L, Chuang I, Villasante ED. Correction: Vaccine Strain-Specificity of Protective HLA-Restricted Class 1 P. falciparum Epitopes. PLoS One 2016; 11:e0168952. [PMID: 27997615 PMCID: PMC5173278 DOI: 10.1371/journal.pone.0168952] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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5
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Sedegah M, Peters B, Hollingdale MR, Ganeshan HD, Huang J, Farooq F, Belmonte MN, Belmonte AD, Limbach KJ, Diggs C, Soisson L, Chuang I, Villasante ED. Vaccine Strain-Specificity of Protective HLA-Restricted Class 1 P. falciparum Epitopes. PLoS One 2016; 11:e0163026. [PMID: 27695088 PMCID: PMC5047630 DOI: 10.1371/journal.pone.0163026] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [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: 05/13/2016] [Accepted: 09/01/2016] [Indexed: 11/19/2022] Open
Abstract
A DNA prime/adenovirus boost malaria vaccine encoding Plasmodium falciparum strain 3D7 CSP and AMA1 elicited sterile clinical protection associated with CD8+ T cell interferon-gamma (IFN-γ) cells responses directed to HLA class 1-restricted AMA1 epitopes of the vaccine strain 3D7. Since a highly effective malaria vaccine must be broadly protective against multiple P. falciparum strains, we compared these AMA1 epitopes of two P. falciparum strains (7G8 and 3D7), which differ by single amino acid substitutions, in their ability to recall CD8+ T cell activities using ELISpot and flow cytometry/intracellular staining assays. The 7G8 variant peptides did not recall 3D7 vaccine-induced CD8+ T IFN-γ cell responses in these assays, suggesting that protection may be limited to the vaccine strain. The predicted MHC binding affinities of the 7G8 variant epitopes were similar to the 3D7 epitopes, suggesting that the amino acid substitutions of the 7G8 variants may have interfered with TCR recognition of the MHC:peptide complex or that the 7G8 variant may have acted as an altered peptide ligand. These results stress the importance of functional assays in defining protective epitopes. Clinical Trials Registrations: NCT00870987, NCT00392015
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Affiliation(s)
- Martha Sedegah
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, 20910, United States of America
| | - Bjoern Peters
- La Jolla Institute for Allergy and Immunology, La Jolla, CA, 92037, United States of America
| | - Michael R. Hollingdale
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, 20910, United States of America
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD, 20817, United States of America
- * E-mail:
| | - Harini D. Ganeshan
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, 20910, United States of America
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD, 20817, United States of America
| | - Jun Huang
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, 20910, United States of America
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD, 20817, United States of America
| | - Fouzia Farooq
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, 20910, United States of America
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD, 20817, United States of America
| | - Maria N. Belmonte
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, 20910, United States of America
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD, 20817, United States of America
| | - Arnel D. Belmonte
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, 20910, United States of America
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD, 20817, United States of America
| | - Keith J. Limbach
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, 20910, United States of America
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, MD, 20817, United States of America
| | - Carter Diggs
- USAID, Washington, DC, 20523, United States of America
| | | | - Ilin Chuang
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, 20910, United States of America
| | - Eileen D. Villasante
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, 20910, United States of America
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Graves SF, Kouriba B, Diarra I, Daou M, Niangaly A, Coulibaly D, Keita Y, Laurens MB, Berry AA, Vekemans J, Ripley Ballou W, Lanar DE, Dutta S, Gray Heppner D, Soisson L, Diggs CL, Thera MA, Doumbo OK, Plowe CV, Sztein MB, Lyke KE. Strain-specific Plasmodium falciparum multifunctional CD4+ T cell cytokine expression in Malian children immunized with the FMP2.1/AS02A vaccine candidate. Vaccine 2016; 34:2546-55. [DOI: 10.1016/j.vaccine.2016.04.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2015] [Revised: 03/24/2016] [Accepted: 04/07/2016] [Indexed: 12/17/2022]
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Sedegah M, Hollingdale MR, Farooq F, Ganeshan H, Belmonte M, Kim Y, Peters B, Sette A, Huang J, McGrath S, Abot E, Limbach K, Shi M, Soisson L, Diggs C, Chuang I, Tamminga C, Epstein JE, Villasante E, Richie TL. Sterile immunity to malaria after DNA prime/adenovirus boost immunization is associated with effector memory CD8+T cells targeting AMA1 class I epitopes. PLoS One 2014; 9:e106241. [PMID: 25211344 PMCID: PMC4161338 DOI: 10.1371/journal.pone.0106241] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Accepted: 07/29/2014] [Indexed: 11/24/2022] Open
Abstract
Background Fifteen volunteers were immunized with three doses of plasmid DNA encoding P. falciparum circumsporozoite protein (CSP) and apical membrane antigen-1 (AMA1) and boosted with human adenovirus-5 (Ad) expressing the same antigens (DNA/Ad). Four volunteers (27%) demonstrated sterile immunity to controlled human malaria infection and, overall, protection was statistically significantly associated with ELISpot and CD8+ T cell IFN-γ activities to AMA1 but not CSP. DNA priming was required for protection, as 18 additional subjects immunized with Ad alone (AdCA) did not develop sterile protection. Methodology/Principal Findings We sought to identify correlates of protection, recognizing that DNA-priming may induce different responses than AdCA alone. Among protected volunteers, two and three had higher ELISpot and CD8+ T cell IFN-γ responses to CSP and AMA1, respectively, than non-protected volunteers. Unexpectedly, non-protected volunteers in the AdCA trial showed ELISpot and CD8+ T cell IFN-γ responses to AMA1 equal to or higher than the protected volunteers. T cell functionality assessed by intracellular cytokine staining for IFN-γ, TNF-α and IL-2 likewise did not distinguish protected from non-protected volunteers across both trials. However, three of the four protected volunteers showed higher effector to central memory CD8+ T cell ratios to AMA1, and one of these to CSP, than non-protected volunteers for both antigens. These responses were focused on discrete regions of CSP and AMA1. Class I epitopes restricted by A*03 or B*58 supertypes within these regions of AMA1 strongly recalled responses in three of four protected volunteers. We hypothesize that vaccine-induced effector memory CD8+ T cells recognizing a single class I epitope can confer sterile immunity to P. falciparum in humans. Conclusions/Significance We suggest that better understanding of which epitopes within malaria antigens can confer sterile immunity and design of vaccine approaches that elicit responses to these epitopes will increase the potency of next generation gene-based vaccines.
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Affiliation(s)
- Martha Sedegah
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- * E-mail:
| | - Michael R. Hollingdale
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Fouzia Farooq
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Harini Ganeshan
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Maria Belmonte
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Yohan Kim
- La Jolla Institute for Allergy and Immunology, La Jolla, California, United States of America
| | - Bjoern Peters
- La Jolla Institute for Allergy and Immunology, La Jolla, California, United States of America
| | - Alessandro Sette
- La Jolla Institute for Allergy and Immunology, La Jolla, California, United States of America
| | - Jun Huang
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Shannon McGrath
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Esteban Abot
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Keith Limbach
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Meng Shi
- Division of Medical, Audio, Visual, Library and Statistical Services, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | | | | | - Ilin Chuang
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Cindy Tamminga
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Judith E. Epstein
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Eileen Villasante
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Thomas L. Richie
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
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Sedegah M, Kim Y, Ganeshan H, Huang J, Belmonte M, Abot E, Banania JG, Farooq F, McGrath S, Peters B, Sette A, Soisson L, Diggs C, Doolan DL, Tamminga C, Villasante E, Hollingdale MR, Richie TL. Identification of minimal human MHC-restricted CD8+ T-cell epitopes within the Plasmodium falciparum circumsporozoite protein (CSP). Malar J 2013; 12:185. [PMID: 23738590 PMCID: PMC3683343 DOI: 10.1186/1475-2875-12-185] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [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: 03/02/2013] [Accepted: 05/23/2013] [Indexed: 01/14/2023] Open
Abstract
Background Plasmodium falciparum circumsporozoite protein (CSP) is a leading malaria vaccine candidate antigen, known to elicit protective antibody responses in humans (RTS,S vaccine). Recently, a DNA prime / adenovirus (Ad) vector boost vaccine encoding CSP and a second P. falciparum antigen, apical membrane antigen-1, also elicited sterile protection, but in this case associated with interferon gamma ELISpot and CD8+ T cell but not antibody responses. The finding that CSP delivered by an appropriate vaccine platform likely elicits protective cell-mediated immunity provided a rationale for identifying class I-restricted epitopes within this leading vaccine candidate antigen. Methods Limited samples of peripheral blood mononuclear cells from clinical trials of the Ad vaccine were used to identify CD8+ T cell epitopes within pools of overlapping 15mer peptides spanning portions of CSP that stimulated recall responses. Computerized algorithms (NetMHC) predicted 17 minimal class I-restricted 9-10mer epitopes within fifteen 15mers positive in ELISpot assay using PBMC from 10 HLA-matched study subjects. Four additional epitopes were subsequently predicted using NetMHC, matched to other study subjects without initial 15mer ELISpot screening. Nine of the putative epitopes were synthesized and tested by ELISpot assay, and six of these nine were further tested for CD8+ T cell responses by ELISpot CD4+ and CD8+ T cell-depletion and flow cytometry assays for evidence of CD8+ T cell dependence. Results Each of the nine putative epitopes, all sequence-conserved, recalled responses from HLA-matched CSP-immunized research subjects. Four shorter sequences contained within these sequences were identified using NetMHC predictions and may have contributed to recall responses. Five (9-10mer) epitopes were confirmed to be targets of CD8+ T cell responses using ELISpot depletion and ICS assays. Two 9mers among these nine epitopes were each restricted by two HLA supertypes (A01/B07; A01A24/A24) and one 9mer was restricted by three HLA supertypes (A01A24/A24/B27) indicating that some CSP class I-restricted epitopes, like DR epitopes, may be HLA-promiscuous. Conclusions This study identified nine and confirmed five novel class I epitopes restricted by six HLA supertypes, suggesting that an adenovirus-vectored CSP vaccine would be immunogenic and potentially protective in genetically diverse populations.
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Affiliation(s)
- Martha Sedegah
- US Military Malaria Vaccine Program, Naval Medical Research Center, Walter Reed Army Institute of Research, Silver Spring, MD, USA.
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Chuang I, Sedegah M, Cicatelli S, Spring M, Polhemus M, Tamminga C, Patterson N, Guerrero M, Bennett JW, McGrath S, Ganeshan H, Belmonte M, Farooq F, Abot E, Banania JG, Huang J, Newcomer R, Rein L, Litilit D, Richie NO, Wood C, Murphy J, Sauerwein R, Hermsen CC, McCoy AJ, Kamau E, Cummings J, Komisar J, Sutamihardja A, Shi M, Epstein JE, Maiolatesi S, Tosh D, Limbach K, Angov E, Bergmann-Leitner E, Bruder JT, Doolan DL, King CR, Carucci D, Dutta S, Soisson L, Diggs C, Hollingdale MR, Ockenhouse CF, Richie TL. DNA prime/Adenovirus boost malaria vaccine encoding P. falciparum CSP and AMA1 induces sterile protection associated with cell-mediated immunity. PLoS One 2013; 8:e55571. [PMID: 23457473 PMCID: PMC3573028 DOI: 10.1371/journal.pone.0055571] [Citation(s) in RCA: 110] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Accepted: 12/24/2012] [Indexed: 12/25/2022] Open
Abstract
Background Gene-based vaccination using prime/boost regimens protects animals and humans against malaria, inducing cell-mediated responses that in animal models target liver stage malaria parasites. We tested a DNA prime/adenovirus boost malaria vaccine in a Phase 1 clinical trial with controlled human malaria infection. Methodology/Principal Findings The vaccine regimen was three monthly doses of two DNA plasmids (DNA) followed four months later by a single boost with two non-replicating human serotype 5 adenovirus vectors (Ad). The constructs encoded genes expressing P. falciparum circumsporozoite protein (CSP) and apical membrane antigen-1 (AMA1). The regimen was safe and well-tolerated, with mostly mild adverse events that occurred at the site of injection. Only one AE (diarrhea), possibly related to immunization, was severe (Grade 3), preventing daily activities. Four weeks after the Ad boost, 15 study subjects were challenged with P. falciparum sporozoites by mosquito bite, and four (27%) were sterilely protected. Antibody responses by ELISA rose after Ad boost but were low (CSP geometric mean titer 210, range 44–817; AMA1 geometric mean micrograms/milliliter 11.9, range 1.5–102) and were not associated with protection. Ex vivo IFN-γ ELISpot responses after Ad boost were modest (CSP geometric mean spot forming cells/million peripheral blood mononuclear cells 86, range 13–408; AMA1 348, range 88–1270) and were highest in three protected subjects. ELISpot responses to AMA1 were significantly associated with protection (p = 0.019). Flow cytometry identified predominant IFN-γ mono-secreting CD8+ T cell responses in three protected subjects. No subjects with high pre-existing anti-Ad5 neutralizing antibodies were protected but the association was not statistically significant. Significance The DNA/Ad regimen provided the highest sterile immunity achieved against malaria following immunization with a gene-based subunit vaccine (27%). Protection was associated with cell-mediated immunity to AMA1, with CSP probably contributing. Substituting a low seroprevalence vector for Ad5 and supplementing CSP/AMA1 with additional antigens may improve protection. Trial Registration ClinicalTrials.govNCT00870987.
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MESH Headings
- Adenoviruses, Human/genetics
- Adenoviruses, Human/immunology
- Adolescent
- Adult
- Antigens, Protozoan/genetics
- Antigens, Protozoan/immunology
- CD8-Positive T-Lymphocytes/immunology
- Female
- Humans
- Immunity, Cellular
- Interferon-gamma/immunology
- Malaria Vaccines/adverse effects
- Malaria Vaccines/genetics
- Malaria Vaccines/immunology
- Malaria Vaccines/therapeutic use
- Malaria, Falciparum/immunology
- Malaria, Falciparum/parasitology
- Malaria, Falciparum/prevention & control
- Male
- Membrane Proteins/genetics
- Membrane Proteins/immunology
- Middle Aged
- Plasmodium falciparum/genetics
- Plasmodium falciparum/immunology
- Protozoan Proteins/genetics
- Protozoan Proteins/immunology
- Vaccines, DNA/adverse effects
- Vaccines, DNA/genetics
- Vaccines, DNA/immunology
- Vaccines, DNA/therapeutic use
- Young Adult
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Affiliation(s)
- Ilin Chuang
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Martha Sedegah
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Susan Cicatelli
- US Military Malaria Vaccine Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Michele Spring
- US Military Malaria Vaccine Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Mark Polhemus
- US Military Malaria Vaccine Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Cindy Tamminga
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Noelle Patterson
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Melanie Guerrero
- US Military Malaria Vaccine Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Jason W. Bennett
- US Military Malaria Vaccine Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Shannon McGrath
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Harini Ganeshan
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Maria Belmonte
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Fouzia Farooq
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Esteban Abot
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Jo Glenna Banania
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Jun Huang
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Rhonda Newcomer
- US Military Malaria Vaccine Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Lisa Rein
- US Military Malaria Vaccine Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Dianne Litilit
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Nancy O. Richie
- US Military Malaria Vaccine Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Chloe Wood
- US Military Malaria Vaccine Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Jittawadee Murphy
- US Military Malaria Vaccine Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Robert Sauerwein
- Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
| | | | - Andrea J. McCoy
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Edwin Kamau
- US Military Malaria Vaccine Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - James Cummings
- US Military Malaria Vaccine Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Jack Komisar
- US Military Malaria Vaccine Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Awalludin Sutamihardja
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Meng Shi
- US Military Malaria Vaccine Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Judith E. Epstein
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Santina Maiolatesi
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Donna Tosh
- US Military Malaria Vaccine Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Keith Limbach
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Evelina Angov
- US Military Malaria Vaccine Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Elke Bergmann-Leitner
- US Military Malaria Vaccine Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | | | - Denise L. Doolan
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - C. Richter King
- GenVec, Inc., Gaithersburg, Maryland, United States of America
| | - Daniel Carucci
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Sheetij Dutta
- US Military Malaria Vaccine Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | | | - Carter Diggs
- USAID, Washington, D. C., United States of America
| | - Michael R. Hollingdale
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
| | - Christian F. Ockenhouse
- US Military Malaria Vaccine Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Thomas L. Richie
- US Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America
- * E-mail:
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Otsyula N, Angov E, Bergmann-Leitner E, Koech M, Khan F, Bennett J, Otieno L, Cummings J, Andagalu B, Tosh D, Waitumbi J, Richie N, Shi M, Miller L, Otieno W, Otieno GA, Ware L, House B, Godeaux O, Dubois MC, Ogutu B, Ballou WR, Soisson L, Diggs C, Cohen J, Polhemus M, Heppner DG, Ockenhouse CF, Spring MD. Results from tandem Phase 1 studies evaluating the safety, reactogenicity and immunogenicity of the vaccine candidate antigen Plasmodium falciparum FVO merozoite surface protein-1 (MSP1(42)) administered intramuscularly with adjuvant system AS01. Malar J 2013; 12:29. [PMID: 23342996 PMCID: PMC3582548 DOI: 10.1186/1475-2875-12-29] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [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: 08/17/2012] [Accepted: 01/14/2013] [Indexed: 01/06/2023] Open
Abstract
Background The development of an asexual blood stage vaccine against Plasmodium falciparum malaria based on the major merozoite surface protein-1 (MSP1) antigen is founded on the protective efficacy observed in preclinical studies and induction of invasion and growth inhibitory antibody responses. The 42 kDa C-terminus of MSP1 has been developed as the recombinant protein vaccine antigen, and the 3D7 allotype, formulated with the Adjuvant System AS02A, has been evaluated extensively in human clinical trials. In preclinical rabbit studies, the FVO allele of MSP142 has been shown to have improved immunogenicity over the 3D7 allele, in terms of antibody titres as well as growth inhibitory activity of antibodies against both the heterologous 3D7 and homologous FVO parasites. Methods Two Phase 1 clinical studies were conducted to examine the safety, reactogenicity and immunogenicity of the FVO allele of MSP142 in the adjuvant system AS01 administered intramuscularly at 0-, 1-, and 2-months: one in the USA and, after evaluation of safety data results, one in Western Kenya. The US study was an open-label, dose escalation study of 10 and 50 μg doses of MSP142 in 26 adults, while the Kenya study, evaluating 30 volunteers, was a double-blind, randomized study of only the 50 μg dose with a rabies vaccine comparator. Results In these studies it was demonstrated that this vaccine formulation has an acceptable safety profile and is immunogenic in malaria-naïve and malaria-experienced populations. High titres of anti-MSP1 antibodies were induced in both study populations, although there was a limited number of volunteers whose serum demonstrated significant inhibition of blood-stage parasites as measured by growth inhibition assay. In the US volunteers, the antibodies generated exhibited better cross-reactivity to heterologous MSP1 alleles than a MSP1-based vaccine (3D7 allele) previously tested at both study sites. Conclusions Given that the primary effector mechanism for blood stage vaccine targets is humoral, the antibody responses demonstrated to this vaccine candidate, both quantitative (total antibody titres) and qualitative (functional antibodies inhibiting parasite growth) warrant further consideration of its application in endemic settings. Trial registrations Clinical Trials NCT00666380
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Affiliation(s)
- Nekoye Otsyula
- Walter Reed Project, Kenya Medical Research Institute, Kisumu, Kenya
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11
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Ouattara A, Takala-Harrison S, Thera MA, Coulibaly D, Niangaly A, Saye R, Tolo Y, Dutta S, Heppner DG, Soisson L, Diggs CL, Vekemans J, Cohen J, Blackwelder WC, Dube T, Laurens MB, Doumbo OK, Plowe CV. Molecular basis of allele-specific efficacy of a blood-stage malaria vaccine: vaccine development implications. J Infect Dis 2012. [PMID: 23204168 DOI: 10.1093/infdis/jis709] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The disappointing efficacy of blood-stage malaria vaccines may be explained in part by allele-specific immune responses that are directed against polymorphic epitopes on blood-stage antigens. FMP2.1/AS02(A), a blood-stage candidate vaccine based on apical membrane antigen 1 (AMA1) from the 3D7 strain of Plasmodium falciparum, had allele-specific efficacy against clinical malaria in a phase II trial in Malian children. We assessed the cross-protective efficacy of the malaria vaccine and inferred which polymorphic amino acid positions in AMA1 were the targets of protective allele-specific immune responses. FMP2.1/AS02(A) had the highest efficacy against AMA1 alleles that were identical to the 3D7 vaccine-type allele at 8 highly polymorphic amino acid positions in the cluster 1 loop (c1L) but differed from 3D7 elsewhere in the molecule. Comparison of the incidence of vaccine-type alleles before and after vaccination in the malaria vaccine and control groups and examination of the patterns of allele change at polymorphic positions in consecutive malaria episodes suggest that the highly polymorphic amino acid position 197 in c1L was the most critical determinant of allele-specific efficacy. These results indicate that a multivalent AMA1 vaccine with broad efficacy could include only a limited set of key alleles of this extremely polymorphic antigen.
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Affiliation(s)
- Amed Ouattara
- Malaria Research and Training Center, University of Sciences, Techniques and Technology, Bamako, Mali
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12
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Sedegah M, Tamminga C, McGrath S, House B, Ganeshan H, Lejano J, Abot E, Banania GJ, Sayo R, Farooq F, Belmonte M, Manohar N, Richie NO, Wood C, Long CA, Regis D, Williams FT, Shi M, Chuang I, Spring M, Epstein JE, Mendoza-Silveiras J, Limbach K, Patterson NB, Bruder JT, Doolan DL, King CR, Soisson L, Diggs C, Carucci D, Dutta S, Hollingdale MR, Ockenhouse CF, Richie TL. Adenovirus 5-vectored P. falciparum vaccine expressing CSP and AMA1. Part A: safety and immunogenicity in seronegative adults. PLoS One 2011; 6:e24586. [PMID: 22003383 PMCID: PMC3189181 DOI: 10.1371/journal.pone.0024586] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2010] [Accepted: 08/15/2011] [Indexed: 11/24/2022] Open
Abstract
Background Models of immunity to malaria indicate the importance of CD8+ T cell responses for targeting intrahepatic stages and antibodies for targeting sporozoite and blood stages. We designed a multistage adenovirus 5 (Ad5)-vectored Plasmodium falciparum malaria vaccine, aiming to induce both types of responses in humans, that was tested for safety and immunogenicity in a Phase 1 dose escalation trial in Ad5-seronegative volunteers. Methodology/Principal Findings The NMRC-M3V-Ad-PfCA vaccine combines two adenovectors encoding circumsporozoite protein (CSP) and apical membrane antigen-1 (AMA1). Group 1 (n = 6) healthy volunteers received one intramuscular injection of 2×10∧10 particle units (1×10∧10 each construct) and Group 2 (n = 6) a five-fold higher dose. Transient, mild to moderate adverse events were more pronounced with the higher dose. ELISpot responses to CSP and AMA1 peaked at 1 month, were higher in the low dose (geomean CSP = 422, AMA1 = 862 spot forming cells/million) than in the high dose (CSP = 154, p = 0.049, AMA1 = 423, p = 0.045) group and were still positive at 12 months in a number of volunteers. ELISpot depletion assays identified dependence on CD4+ or on both CD4+ and CD8+ T cells, with few responses dependent only on CD8+ T cells. Intracellular cytokine staining detected stronger CD8+ than CD4+ T cell IFN-γ responses (CSP p = 0.0001, AMA1 p = 0.003), but similar frequencies of multifunctional CD4+ and CD8+ T cells secreting two or more of IFN-γ, TNF-α or IL-2. Median fluorescence intensities were 7–10 fold higher in triple than single secreting cells. Antibody responses were low but trended higher in the high dose group and did not inhibit growth of cultured P. falciparum blood stage parasites. Significance As found in other trials, adenovectored vaccines appeared safe and well-tolerated at doses up to 1×10∧11 particle units. This is the first demonstration in humans of a malaria vaccine eliciting strong CD8+ T cell IFN-γ responses. Trial Registration ClinicalTrials.govNCT00392015
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Affiliation(s)
- Martha Sedegah
- U.S. Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America.
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13
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Tamminga C, Sedegah M, Regis D, Chuang I, Epstein JE, Spring M, Mendoza-Silveiras J, McGrath S, Maiolatesi S, Reyes S, Steinbeiss V, Fedders C, Smith K, House B, Ganeshan H, Lejano J, Abot E, Banania GJ, Sayo R, Farooq F, Belmonte M, Murphy J, Komisar J, Williams J, Shi M, Brambilla D, Manohar N, Richie NO, Wood C, Limbach K, Patterson NB, Bruder JT, Doolan DL, King CR, Diggs C, Soisson L, Carucci D, Levine G, Dutta S, Hollingdale MR, Ockenhouse CF, Richie TL. Adenovirus-5-vectored P. falciparum vaccine expressing CSP and AMA1. Part B: safety, immunogenicity and protective efficacy of the CSP component. PLoS One 2011; 6:e25868. [PMID: 22003411 PMCID: PMC3189219 DOI: 10.1371/journal.pone.0025868] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Accepted: 09/12/2011] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND A protective malaria vaccine will likely need to elicit both cell-mediated and antibody responses. As adenovirus vaccine vectors induce both these responses in humans, a Phase 1/2a clinical trial was conducted to evaluate the efficacy of an adenovirus serotype 5-vectored malaria vaccine against sporozoite challenge. METHODOLOGY/PRINCIPAL FINDINGS NMRC-MV-Ad-PfC is an adenovirus vector encoding the Plasmodium falciparum 3D7 circumsporozoite protein (CSP). It is one component of a two-component vaccine NMRC-M3V-Ad-PfCA consisting of one adenovector encoding CSP and one encoding apical membrane antigen-1 (AMA1) that was evaluated for safety and immunogenicity in an earlier study (see companion paper, Sedegah et al). Fourteen Ad5 seropositive or negative adults received two doses of NMRC-MV-Ad-PfC sixteen weeks apart, at 1 x 1010 particle units per dose. The vaccine was safe and well tolerated. All volunteers developed positive ELISpot responses by 28 days after the first immunization (geometric mean 272 spot forming cells/million[sfc/m]) that declined during the following 16 weeks and increased after the second dose to levels that in most cases were less than the initial peak (geometric mean 119 sfc/m). CD8+ predominated over CD4+ responses, as in the first clinical trial. Antibody responses were poor and like ELISpot responses increased after the second immunization but did not exceed the initial peak. Pre-existing neutralizing antibodies (NAb) to Ad5 did not affect the immunogenicity of the first dose, but the fold increase in NAb induced by the first dose was significantly associated with poorer antibody responses after the second dose, while ELISpot responses remained unaffected. When challenged by the bite of P. falciparum-infected mosquitoes, two of 11 volunteers showed a delay in the time to patency compared to infectivity controls, but no volunteers were sterilely protected. SIGNIFICANCE The NMRC-MV-Ad-PfC vaccine expressing CSP was safe and well tolerated given as two doses, but did not provide sterile protection. TRIAL REGISTRATION ClinicalTrials.gov NCT00392015.
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Affiliation(s)
- Cindy Tamminga
- U.S. Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, Maryland, United States of America.
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14
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Thera MA, Doumbo OK, Coulibaly D, Laurens MB, Ouattara A, Kone AK, Guindo AB, Traore K, Traore I, Kouriba B, Diallo DA, Diarra I, Daou M, Dolo A, Tolo Y, Sissoko MS, Niangaly A, Sissoko M, Takala-Harrison S, Lyke KE, Wu Y, Blackwelder WC, Godeaux O, Vekemans J, Dubois MC, Ballou WR, Cohen J, Thompson D, Dube T, Soisson L, Diggs CL, House B, Lanar DE, Dutta S, Heppner DG, Plowe CV. A field trial to assess a blood-stage malaria vaccine. N Engl J Med 2011; 365:1004-13. [PMID: 21916638 PMCID: PMC3242358 DOI: 10.1056/nejmoa1008115] [Citation(s) in RCA: 275] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
BACKGROUND Blood-stage malaria vaccines are intended to prevent clinical disease. The malaria vaccine FMP2.1/AS02(A), a recombinant protein based on apical membrane antigen 1 (AMA1) from the 3D7 strain of Plasmodium falciparum, has previously been shown to have immunogenicity and acceptable safety in Malian adults and children. METHODS In a double-blind, randomized trial, we immunized 400 Malian children with either the malaria vaccine or a control (rabies) vaccine and followed them for 6 months. The primary end point was clinical malaria, defined as fever and at least 2500 parasites per cubic millimeter of blood. A secondary end point was clinical malaria caused by parasites with the AMA1 DNA sequence found in the vaccine strain. RESULTS The cumulative incidence of the primary end point was 48.4% in the malaria-vaccine group and 54.4% in the control group; efficacy against the primary end point was 17.4% (hazard ratio for the primary end point, 0.83; 95% confidence interval [CI], 0.63 to 1.09; P=0.18). Efficacy against the first and subsequent episodes of clinical malaria, as defined on the basis of various parasite-density thresholds, was approximately 20%. Efficacy against clinical malaria caused by parasites with AMA1 corresponding to that of the vaccine strain was 64.3% (hazard ratio, 0.36; 95% CI, 0.08 to 0.86; P=0.03). Local reactions and fever after vaccination were more frequent with the malaria vaccine. CONCLUSIONS On the basis of the primary end point, the malaria vaccine did not provide significant protection against clinical malaria, but on the basis of secondary results, it may have strain-specific efficacy. If this finding is confirmed, AMA1 might be useful in a multicomponent malaria vaccine. (Funded by the National Institute of Allergy and Infectious Diseases and others; ClinicalTrials.gov number, NCT00460525.).
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Affiliation(s)
- Mahamadou A Thera
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
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15
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Thera MA, Doumbo OK, Coulibaly D, Laurens MB, Kone AK, Guindo AB, Traore K, Sissoko M, Diallo DA, Diarra I, Kouriba B, Daou M, Dolo A, Baby M, Sissoko MS, Sagara I, Niangaly A, Traore I, Olotu A, Godeaux O, Leach A, Dubois MC, Ballou WR, Cohen J, Thompson D, Dube T, Soisson L, Diggs CL, Takala SL, Lyke KE, House B, Lanar DE, Dutta S, Heppner DG, Plowe CV. Safety and immunogenicity of an AMA1 malaria vaccine in Malian children: results of a phase 1 randomized controlled trial. PLoS One 2010; 5:e9041. [PMID: 20140214 PMCID: PMC2816207 DOI: 10.1371/journal.pone.0009041] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [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: 06/23/2009] [Accepted: 01/07/2010] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The objective was to evaluate the safety and immunogenicity of the AMA1-based malaria vaccine FMP2.1/AS02(A) in children exposed to seasonal falciparum malaria. METHODOLOGY/PRINCIPAL FINDINGS A Phase 1 double blind randomized controlled dose escalation trial was conducted in Bandiagara, Mali, West Africa, a rural town with intense seasonal transmission of Plasmodium falciparum malaria. The malaria vaccine FMP2.1/AS02(A) is a recombinant protein (FMP2.1) based on apical membrane antigen 1 (AMA1) from the 3D7 clone of P. falciparum, formulated in the Adjuvant System AS02(A). The comparator vaccine was a cell-culture rabies virus vaccine (RabAvert). One hundred healthy Malian children aged 1-6 years were recruited into 3 cohorts and randomized to receive either 10 microg FMP2.1 in 0.1 mL AS02(A), or 25 microg FMP2.1 in 0.25 mL AS02(A), or 50 microg FMP2.1 50 microg in 0.5 mL AS02(A), or rabies vaccine. Three doses of vaccine were given at 0, 1 and 2 months, and children were followed for 1 year. Solicited symptoms were assessed for 7 days and unsolicited symptoms for 30 days after each vaccination. Serious adverse events were assessed throughout the study. Transient local pain and swelling were common and more frequent in all malaria vaccine dosage groups than in the comparator group, but were acceptable to parents of participants. Levels of anti-AMA1 antibodies measured by ELISA increased significantly (at least 100-fold compared to baseline) in all 3 malaria vaccine groups, and remained high during the year of follow up. CONCLUSION/SIGNIFICANCE The FMP2.1/AS02(A) vaccine had a good safety profile, was well-tolerated, and induced high and sustained antibody levels in malaria-exposed children. This malaria vaccine is being evaluated in a Phase 2 efficacy trial in children at this site. TRIAL REGISTRATION ClinicalTrials.gov NCT00358332 [NCT00358332].
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Affiliation(s)
- Mahamadou A. Thera
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Ogobara K. Doumbo
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Drissa Coulibaly
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Matthew B. Laurens
- Howard Hughes Medical Institute/Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Abdoulaye K. Kone
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Ando B. Guindo
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Karim Traore
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Mady Sissoko
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Dapa A. Diallo
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Issa Diarra
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Bourema Kouriba
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Modibo Daou
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Amagana Dolo
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Mounirou Baby
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | | | - Issaka Sagara
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Amadou Niangaly
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Idrissa Traore
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Ally Olotu
- GlaxoSmithKline Biologicals, Rixensart, Belgium
| | | | | | | | | | - Joe Cohen
- GlaxoSmithKline Biologicals, Rixensart, Belgium
| | - Darby Thompson
- EMMES Corporation, Rockville, Maryland, United States of America
| | - Tina Dube
- EMMES Corporation, Rockville, Maryland, United States of America
| | - Lorraine Soisson
- Malaria Vaccine Development Program, U.S. Agency for International Development, Washington, D.C., United States of America
| | - Carter L. Diggs
- Malaria Vaccine Development Program, U.S. Agency for International Development, Washington, D.C., United States of America
| | - Shannon L. Takala
- Howard Hughes Medical Institute/Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Kirsten E. Lyke
- Howard Hughes Medical Institute/Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Brent House
- Division of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - David E. Lanar
- Division of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Sheetij Dutta
- Division of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - D. Gray Heppner
- Division of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Christopher V. Plowe
- Howard Hughes Medical Institute/Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
- * E-mail:
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16
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Dutta S, Sullivan JS, Grady KK, Haynes JD, Komisar J, Batchelor AH, Soisson L, Diggs CL, Heppner DG, Lanar DE, Collins WE, Barnwell JW. High antibody titer against apical membrane antigen-1 is required to protect against malaria in the Aotus model. PLoS One 2009; 4:e8138. [PMID: 19997632 PMCID: PMC2780715 DOI: 10.1371/journal.pone.0008138] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2009] [Accepted: 10/23/2009] [Indexed: 11/19/2022] Open
Abstract
A Plasmodium falciparum 3D7 strain Apical Membrane Antigen-1 (AMA1) vaccine, formulated with AS02A adjuvant, slowed parasite growth in a recent Phase 1/2a trial, however sterile protection was not observed. We tested this AS02A, and a Montanide ISA720 (ISA) formulation of 3D7 AMA1 in Aotus monkeys. The 3D7 parasite does not invade Aotus erythrocytes, hence two heterologous strains, FCH/4 and FVO, were used for challenge, FCH/4 AMA1 being more homologous to 3D7 than FVO AMA1. Following three vaccinations, the monkeys were challenged with 50,000 FCH/4 or 10,000 FVO parasites. Three of the six animals in the AMA+ISA group were protected against FCH/4 challenge. One monkey did not become parasitemic, another showed only a short period of low level parasitemia that self-cured, and a third animal showed a delay before exhibiting its parasitemic phase. This is the first protection shown in primates with a recombinant P. falciparum AMA1 without formulation in Freund's complete adjuvant. No animals in the AMA+AS02A group were protected, but this group exhibited a trend towards reduced growth rate. A second group of monkeys vaccinated with AMA+ISA vaccine was not protected against FVO challenge, suggesting strain-specificity of AMA1-based protection. Protection against FCH/4 strain correlated with the quantity of induced antibodies, as the protected animals were the only ones to have in vitro parasite growth inhibitory activity of >70% at 1∶10 serum dilution; immuno-fluorescence titers >8,000; ELISA titers against full-length AMA1 >300,000 and ELISA titer against AMA1 domains1+2 >100,000. A negative correlation between log ELISA titer and day 11 cumulative parasitemia (Spearman rank r = −0.780, p value = 0.0001), further confirmed the relationship between antibody titer and protection. High titers of cross-strain inhibitory antibodies against AMA1 are therefore critical to confer solid protection, and the Aotus model can be used to down-select future AMA1 formulations, prior to advanced human trials.
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Affiliation(s)
- Sheetij Dutta
- Department of Epitope Mapping, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
- * E-mail: (SD); (JWB)
| | - JoAnn S. Sullivan
- Malaria Branch, Division of Parasitic Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Katharine K. Grady
- Malaria Branch, Division of Parasitic Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - J. David Haynes
- Division of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Jack Komisar
- Division of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Adrian H. Batchelor
- Department of Epitope Mapping, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Lorraine Soisson
- Malaria Vaccine Development Program, United States Agency for International Development, Washington, D. C., United States of America
| | - Carter L. Diggs
- Malaria Vaccine Development Program, United States Agency for International Development, Washington, D. C., United States of America
| | - D. Gray Heppner
- Division of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - David E. Lanar
- Division of Malaria Vaccine Development, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - William E. Collins
- Malaria Branch, Division of Parasitic Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - John W. Barnwell
- Malaria Branch, Division of Parasitic Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
- * E-mail: (SD); (JWB)
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17
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Spring MD, Cummings JF, Ockenhouse CF, Dutta S, Reidler R, Angov E, Bergmann-Leitner E, Stewart VA, Bittner S, Juompan L, Kortepeter MG, Nielsen R, Krzych U, Tierney E, Ware LA, Dowler M, Hermsen CC, Sauerwein RW, de Vlas SJ, Ofori-Anyinam O, Lanar DE, Williams JL, Kester KE, Tucker K, Shi M, Malkin E, Long C, Diggs CL, Soisson L, Dubois MC, Ballou WR, Cohen J, Heppner DG. Phase 1/2a study of the malaria vaccine candidate apical membrane antigen-1 (AMA-1) administered in adjuvant system AS01B or AS02A. PLoS One 2009; 4:e5254. [PMID: 19390585 PMCID: PMC2669163 DOI: 10.1371/journal.pone.0005254] [Citation(s) in RCA: 163] [Impact Index Per Article: 10.9] [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: 05/30/2008] [Accepted: 03/23/2009] [Indexed: 11/19/2022] Open
Abstract
Background This Phase 1/2a study evaluated the safety, immunogenicity, and efficacy of an experimental malaria vaccine comprised of the recombinant Plasmodium falciparum protein apical membrane antigen-1 (AMA-1) representing the 3D7 allele formulated with either the AS01B or AS02A Adjuvant Systems. Methodology/Principal Findings After a preliminary safety evaluation of low dose AMA-1/AS01B (10 µg/0.5 mL) in 5 adults, 30 malaria-naïve adults were randomly allocated to receive full dose (50 µg/0.5 mL) of AMA-1/AS01B (n = 15) or AMA-1/AS02A (n = 15), followed by a malaria challenge. All vaccinations were administered intramuscularly on a 0-, 1-, 2-month schedule. All volunteers experienced transient injection site erythema, swelling and pain. Two weeks post-third vaccination, anti-AMA-1 Geometric Mean Antibody Concentrations (GMCs) with 95% Confidence Intervals (CIs) were high: low dose AMA-1/AS01B 196 µg/mL (103–371 µg/mL), full dose AMA-1/AS01B 279 µg/mL (210–369 µg/mL) and full dose AMA-1/AS02A 216 µg/mL (169–276 µg/mL) with no significant difference among the 3 groups. The three vaccine formulations elicited equivalent functional antibody responses, as measured by growth inhibition assay (GIA), against homologous but not against heterologous (FVO) parasites as well as demonstrable interferon-gamma (IFN-γ) responses. To assess efficacy, volunteers were challenged with P. falciparum-infected mosquitoes, and all became parasitemic, with no significant difference in the prepatent period by either light microscopy or quantitative polymerase chain reaction (qPCR). However, a small but significant reduction of parasitemia in the AMA-1/AS02A group was seen with a statistical model employing qPCR measurements. Significance All three vaccine formulations were found to be safe and highly immunogenic. These immune responses did not translate into significant vaccine efficacy in malaria-naïve adults employing a primary sporozoite challenge model, but encouragingly, estimation of parasite growth rates from qPCR data may suggest a partial biological effect of the vaccine. Further evaluation of the immunogenicity and efficacy of the AMA-1/AS02A formulation is ongoing in a malaria-experienced pediatric population in Mali. Trial Registration www.clinicaltrials.govNCT00385047
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Affiliation(s)
- Michele D Spring
- United States Military Malaria Vaccine Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America.
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18
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Polhemus ME, Magill AJ, Cummings JF, Kester KE, Ockenhouse CF, Lanar DE, Dutta S, Barbosa A, Soisson L, Diggs CL, Robinson SA, Haynes JD, Stewart VA, Ware LA, Brando C, Krzych U, Bowden RA, Cohen JD, Dubois MC, Ofori-Anyinam O, De-Kock E, Ballou WR, Heppner DG. Phase I dose escalation safety and immunogenicity trial of Plasmodium falciparum apical membrane protein (AMA-1) FMP2.1, adjuvanted with AS02A, in malaria-naïve adults at the Walter Reed Army Institute of Research. Vaccine 2007; 25:4203-12. [PMID: 17442466 DOI: 10.1016/j.vaccine.2007.03.012] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2006] [Revised: 02/21/2007] [Accepted: 03/02/2007] [Indexed: 11/26/2022]
Abstract
We report the first safety and immunogenicity trial of the Plasmodium falciparum vaccine candidate FMP2.1/AS02A, a recombinant E. coli-expressed protein based upon the apical membrane antigen-1 (AMA-1) of the 3D7 clone formulated with the AS02A adjuvant. We conducted an open-label, staggered-start, dose-escalating Phase I trial in 23 malaria-naïve volunteers who received 8, 20 or 40microg of FMP2.1 in a fixed volume of 0.5mL of AS02A on a 0, 1, and 2 month schedule. Nineteen of 23 volunteers received all three scheduled immunizations. The most frequent solicited local and systemic adverse events associated with immunization were injection site pain (68%) and headache (29%). There were no significant laboratory abnormalities or vaccine-related serious adverse events. All volunteers seroconverted after second immunization as determined by ELISA. Immune sera recognized sporozoites and merozoites by immunofluorescence assay (IFA), and exhibited both growth inhibition and processing inhibition activity against homologous (3D7) asexual stage parasites. Post-immunization, peripheral blood mononuculear cells exhibited FMP2.1-specific lymphoproliferation and IFN-gamma and IL-5 ELISPOT assay responses. This is the first PfAMA-1-based vaccine shown to elicit both potent humoral and cellular immunity in humans. Encouraged by the potential of FMP1/AS02A to target host immunity against PfAMA-1 that is known to be expressed by sporozoite, hepatic and erythrocytic stages, we have initiated field trials of FMP2.1/AS02A in an endemic population in the Republic of Mali.
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Affiliation(s)
- Mark E Polhemus
- Walter Reed Army Institute of Research, Silver Spring, MD, United States.
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19
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Stoute JA, Gombe J, Withers MR, Siangla J, McKinney D, Onyango M, Cummings JF, Milman J, Tucker K, Soisson L, Stewart VA, Lyon JA, Angov E, Leach A, Cohen J, Kester KE, Ockenhouse CF, Holland CA, Diggs CL, Wittes J, Heppner DG. Phase 1 randomized double-blind safety and immunogenicity trial of Plasmodium falciparum malaria merozoite surface protein FMP1 vaccine, adjuvanted with AS02A, in adults in western Kenya. Vaccine 2007; 25:176-84. [PMID: 16388879 DOI: 10.1016/j.vaccine.2005.11.037] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2005] [Revised: 10/29/2005] [Accepted: 11/18/2005] [Indexed: 11/22/2022]
Abstract
We report the first trial of candidate malaria vaccine antigen FMP1, a 42kDa fragment from the C-terminus of merozoite surface protein-1 (MSP-1) from the 3D7 strain of Plasmodium falciparum, in an endemic area. Forty adult male and female residents of western Kenya were enrolled to receive 3 doses of either FMP1/AS02A or Imovax rabies vaccine by intra-deltoid injection on a 0, 1, 2 month schedule. Thirty-seven volunteers received all three immunizations and 38 completed the 12-month evaluation period. Slightly more recipients of the FMP1/AS02A vaccine experienced any instance of pain at 24 h post-immunization than in the Imovax group (95% versus 65%), but otherwise the two vaccines were equally safe and well-tolerated. Baseline antibody levels were high in both groups and were boosted in the FMP1/AS02A group. Longitudinal models revealed a highly significant difference between groups for both the average post-baseline antibody responses to MSP-1(42) (F1,335=13.16; P<0.001) and the Day 90 responses to MSP-1(42) (F1,335=16.69; P<0.001). The FMP1/AS02A vaccine is safe and immunogenic in adults and should progress to safety testing in children at greatest risk of malaria.
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Affiliation(s)
- José A Stoute
- US Army Medical Research Unit and the Kenya Medical Research Institute, Nairobi, Kenya.
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20
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Thera MA, Doumbo OK, Coulibaly D, Diallo DA, Sagara I, Dicko A, Diemert DJ, Heppner DG, Stewart VA, Angov E, Soisson L, Leach A, Tucker K, Lyke KE, Plowe CV. Safety and allele-specific immunogenicity of a malaria vaccine in Malian adults: results of a phase I randomized trial. PLoS Clin Trials 2006; 1:e34. [PMID: 17124530 PMCID: PMC1851722 DOI: 10.1371/journal.pctr.0010034] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2006] [Accepted: 10/10/2006] [Indexed: 11/18/2022]
Abstract
OBJECTIVES The objectives were to evaluate the safety, reactogenicity, and allele-specific immunogenicity of the blood-stage malaria vaccine FMP1/AS02A in adults exposed to seasonal malaria and the impact of natural infection on vaccine-induced antibody levels. DESIGN We conducted a randomized, double-blind, controlled phase I clinical trial. SETTING Bandiagara, Mali, West Africa, is a rural town with intense seasonal transmission of Plasmodium falciparum malaria. PARTICIPANTS Forty healthy, malaria-experienced Malian adults aged 18-55 y were enrolled. INTERVENTIONS The FMP1/AS02A malaria vaccine is a 42-kDa recombinant protein based on the carboxy-terminal end of merozoite surface protein-1 (MSP-1(42)) from the 3D7 clone of P. falciparum, adjuvanted with AS02A. The control vaccine was a killed rabies virus vaccine (Imovax). Participants were randomized to receive either FMP1/AS02A or rabies vaccine at 0, 1, and 2 mo and were followed for 1 y. OUTCOME MEASURES Solicited and unsolicited adverse events and allele-specific antibody responses to recombinant MSP-1(42) and its subunits derived from P. falciparum strains homologous and heterologous to the 3D7 vaccine strain were measured. RESULTS Transient local pain and swelling were more common in the malaria vaccine group than in the control group (11/20 versus 3/20 and 10/20 versus 6/20, respectively). MSP-1(42) antibody levels rose during the malaria transmission season in the control group, but were significantly higher in malaria vaccine recipients after the second immunization and remained higher after the third immunization relative both to baseline and to the control group. Immunization with the malaria vaccine was followed by significant increases in antibodies recognizing three diverse MSP-1(42) alleles and their subunits. CONCLUSIONS FMP1/AS02A was well tolerated and highly immunogenic in adults exposed to intense seasonal malaria transmission and elicited immune responses to genetically diverse parasite clones. Anti-MSP-1(42) antibody levels followed a seasonal pattern that was significantly augmented and prolonged by the malaria vaccine.
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Affiliation(s)
- Mahamadou A Thera
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Ogobara K Doumbo
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Drissa Coulibaly
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Dapa A Diallo
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Issaka Sagara
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - Alassane Dicko
- Malaria Research and Training Center, University of Bamako, Bamako, Mali
| | - David J Diemert
- Malaria Vaccine Development Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - D. Gray Heppner
- Department of Immunology, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - V. Ann Stewart
- Department of Immunology, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Evelina Angov
- Department of Immunology, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Lorraine Soisson
- United States Agency for International Development, Washington, D. C., United States of America
| | | | - Kathryn Tucker
- Statistics Collaborative, Washington, D. C., United States of America
| | - Kirsten E Lyke
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Christopher V Plowe
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
- * To whom correspondence should be addressed. E-mail:
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21
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Ockenhouse CF, Angov E, Kester KE, Diggs C, Soisson L, Cummings JF, Stewart AV, Palmer DR, Mahajan B, Krzych U, Tornieporth N, Delchambre M, Vanhandenhove M, Ofori-Anyinam O, Cohen J, Lyon JA, Heppner DG. Phase I safety and immunogenicity trial of FMP1/AS02A, a Plasmodium falciparum MSP-1 asexual blood stage vaccine☆. Vaccine 2006; 24:3009-17. [PMID: 16356603 DOI: 10.1016/j.vaccine.2005.11.028] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2005] [Revised: 10/26/2005] [Accepted: 11/01/2005] [Indexed: 11/21/2022]
Abstract
We report the first safety and immunogenicity trial of the Plasmodium falciparum malaria blood stage vaccine candidate, FMP1/AS02A consisting of the FMP1 antigen, an Escherichia coli-expressed His-tagged fusion protein from the 42 kDa C-terminal fragment from the 3D7 clone of the merozoite surface protein 1 formulated in the AS02A adjuvant. An open label, prospective, single-center Phase I dose escalation trial of FMP1/AS02A was conducted in 15 adult malaria-naïve human volunteers to assess safety, reactogenicity, and immunogenicity. The vaccine was safe and well-tolerated and no serious adverse events were observed. The vaccine induced high-titer ELISA and IFA responses in all volunteers. Proliferative and ELISPOT responses were induced to vaccine antigen. Biologically active antibodies were induced as measured by GIA. This study establishes the foundation to further evaluate and measure the vaccine's ability to reduce morbidity and mortality in target populations directly affected by P. falciparum malaria.
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MESH Headings
- Adjuvants, Immunologic/administration & dosage
- Adjuvants, Immunologic/pharmacology
- Adolescent
- Adult
- Animals
- Antibodies, Protozoan/blood
- Drug Combinations
- Enzyme-Linked Immunosorbent Assay
- Female
- Fluorescent Antibody Technique, Indirect
- Humans
- Interferon-gamma/biosynthesis
- L-Lactate Dehydrogenase/analysis
- Lipid A/administration & dosage
- Lipid A/analogs & derivatives
- Lipid A/pharmacology
- Malaria Vaccines/administration & dosage
- Malaria Vaccines/adverse effects
- Malaria Vaccines/immunology
- Male
- Merozoite Surface Protein 1/immunology
- Middle Aged
- Plasmodium falciparum/growth & development
- Plasmodium falciparum/immunology
- Saponins/administration & dosage
- Saponins/pharmacology
- T-Lymphocytes/immunology
- Vaccines, Subunit/administration & dosage
- Vaccines, Subunit/adverse effects
- Vaccines, Subunit/immunology
- Vaccines, Synthetic/administration & dosage
- Vaccines, Synthetic/adverse effects
- Vaccines, Synthetic/immunology
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Affiliation(s)
- Christian F Ockenhouse
- Department of Immunology, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA.
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22
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Heppner DG, Kester KE, Ockenhouse CF, Tornieporth N, Ofori O, Lyon JA, Stewart VA, Dubois P, Lanar DE, Krzych U, Moris P, Angov E, Cummings JF, Leach A, Hall BT, Dutta S, Schwenk R, Hillier C, Barbosa A, Ware LA, Nair L, Darko CA, Withers MR, Ogutu B, Polhemus ME, Fukuda M, Pichyangkul S, Gettyacamin M, Diggs C, Soisson L, Milman J, Dubois MC, Garçon N, Tucker K, Wittes J, Plowe CV, Thera MA, Duombo OK, Pau MG, Goudsmit J, Ballou WR, Cohen J. Towards an RTS,S-based, multi-stage, multi-antigen vaccine against falciparum malaria: progress at the Walter Reed Army Institute of Research. Vaccine 2005; 23:2243-50. [PMID: 15755604 DOI: 10.1016/j.vaccine.2005.01.142] [Citation(s) in RCA: 120] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The goal of the Malaria Vaccine Program at the Walter Reed Army Institute of Research (WRAIR) is to develop a licensed multi-antigen, multi-stage vaccine against Plasmodium falciparum able to prevent all symptomatic manifestations of malaria by preventing parasitemia. A secondary goal is to limit disease in vaccinees that do develop malaria. Malaria prevention will be achieved by inducing humoral and cellular immunity against the pre-erythrocytic circumsporozoite protein (CSP) and the liver stage antigen-1 (LSA-1). The strategy to limit disease will target immune responses against one or more blood stage antigens, merozoite surface protein-1 (MSP-1) and apical merozoite antigen-1 (AMA-1). The induction of T- and B-cell memory to achieve a sustained vaccine response may additionally require immunization with an adenovirus vector such as adenovirus serotype 35. RTS,S, a CSP-derived antigen developed by GlaxoSmithKline Biologicals in collaboration with the Walter Reed Army Institute of Research over the past 17 years, is the cornerstone of our program. RTS,S formulated in AS02A (a GSK proprietary formulation) is the only vaccine candidate shown in field trials to prevent malaria and, in one instance, to limit disease severity. Our vaccine development plan requires proof of an individual antigen's efficacy in a Phase 2 laboratory challenge or field trial prior to its integration into an RTS,S-based, multi-antigen vaccine. Progress has been accelerated through extensive partnerships with industrial, academic, governmental, and non-governmental organizations. Recent safety, immunogenicity, and efficacy trials in the US and Africa are presented, as well as plans for the development of a multi-antigen vaccine.
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Affiliation(s)
- D Gray Heppner
- Walter Reed Army Institute of Research, Department of Immunology, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA.
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23
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Kumar S, Epstein JE, Richie TL, Nkrumah FK, Soisson L, Carucci DJ, Hoffman SL. A multilateral effort to develop DNA vaccines against falciparum malaria. Trends Parasitol 2002; 18:129-35. [PMID: 11854091 DOI: 10.1016/s1471-4922(01)02207-3] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Scientists from several organizations worldwide are working together to develop a multistage, multigene DNA-based vaccine against Plasmodium falciparum malaria. This collaborative vaccine development effort is named Multi-Stage DNA-based Malaria Vaccine Operation. An advisory board of international experts in vaccinology, malariology and field trials provides the scientific oversight to support the operation. This article discusses the rationale for the approach, underlying concepts and the pre-clinical development process, and provides a brief outline of the plans for the clinical testing of a multistage, multiantigen malaria vaccine based on DNA plasmid immunization technology.
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Affiliation(s)
- Sanjai Kumar
- Malaria Program, Naval Medical Research Center, Silver Spring, MD 20910, USA.
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