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Opi DH, Kurtovic L, Chan JA, Horton JL, Feng G, Beeson JG. Multi-functional antibody profiling for malaria vaccine development and evaluation. Expert Rev Vaccines 2021; 20:1257-1272. [PMID: 34530671 DOI: 10.1080/14760584.2021.1981864] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
INTRODUCTION A vaccine would greatly accelerate current global efforts toward malaria elimination. While a partially efficacious vaccine has been achieved for Plasmodium falciparum, a major bottleneck in developing highly efficacious vaccines is a lack of reliable correlates of protection, and the limited application of assays that quantify functional immune responses to evaluate and down-select vaccine candidates in pre-clinical studies and clinical trials. AREAS COVERED In this review, we describe the important role of antibodies in immunity against malaria and detail the nature and functional activities of antibodies against the malaria-causing parasite. We highlight the growing understanding of antibody effector functions against malaria and in vitro assays to measure these functional antibody responses. We discuss the application of these assays to quantify antibody functions in vaccine development and evaluation. EXPERT OPINION It is becoming increasingly clear that multiple antibody effector functions are involved in immunity to malaria. Therefore, we propose that evaluating vaccine candidates needs to move beyond individual assays or measuring IgG magnitude alone. Instead, vaccine evaluation should incorporate the full breadth of antibody response types and harness a wider range of assays measuring functional antibody responses. We propose a 3-tier approach to implementing assays to inform vaccine evaluation.
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Affiliation(s)
- D Herbert Opi
- Life Sciences, Burnet Institute, Melbourne, Australia.,Department of Immunology and Pathology, Monash University, Melbourne, Australia.,Department of Medicine, The Doherty Institute, The University of Melbourne, Melbourne, Australia
| | - Liriye Kurtovic
- Life Sciences, Burnet Institute, Melbourne, Australia.,Department of Immunology and Pathology, Monash University, Melbourne, Australia
| | - Jo-Anne Chan
- Life Sciences, Burnet Institute, Melbourne, Australia.,Department of Immunology and Pathology, Monash University, Melbourne, Australia.,Department of Medicine, The Doherty Institute, The University of Melbourne, Melbourne, Australia
| | - Jessica L Horton
- Life Sciences, Burnet Institute, Melbourne, Australia.,Department of Medicine, The Doherty Institute, The University of Melbourne, Melbourne, Australia
| | - Gaoqian Feng
- Life Sciences, Burnet Institute, Melbourne, Australia.,Department of Medicine, The Doherty Institute, The University of Melbourne, Melbourne, Australia
| | - James G Beeson
- Life Sciences, Burnet Institute, Melbourne, Australia.,Department of Immunology and Pathology, Monash University, Melbourne, Australia.,Department of Medicine, The Doherty Institute, The University of Melbourne, Melbourne, Australia.,Department of Microbiology, Monash University, Clayton, Australia
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2
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Willcox AC, Huber AS, Diouf A, Barrett JR, Silk SE, Pulido D, King LDW, Alanine DGW, Minassian AM, Diakite M, Draper SJ, Long CA, Miura K. Antibodies from malaria-exposed Malians generally interact additively or synergistically with human vaccine-induced RH5 antibodies. CELL REPORTS MEDICINE 2021; 2:100326. [PMID: 34337556 PMCID: PMC8324462 DOI: 10.1016/j.xcrm.2021.100326] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 05/03/2021] [Accepted: 06/04/2021] [Indexed: 11/26/2022]
Abstract
Reticulocyte-binding protein homolog 5 (RH5) is a leading Plasmodium falciparum blood-stage vaccine candidate. Another possible candidate, apical membrane antigen 1 (AMA1), was not efficacious in malaria-endemic populations, likely due to pre-existing antimalarial antibodies that interfered with the activity of vaccine-induced AMA1 antibodies, as judged by in vitro growth inhibition assay (GIA). To determine how pre-existing antibodies interact with vaccine-induced RH5 antibodies, we purify total and RH5-specific immunoglobulin Gs (IgGs) from malaria-exposed Malians and malaria-naive RH5 vaccinees. Infection-induced RH5 antibody titers are much lower than those induced by vaccination, and RH5-specific IgGs show differences in the binding site between the two populations. In GIA, Malian polyclonal IgGs show additive or synergistic interactions with RH5 human monoclonal antibodies and overall additive interactions with vaccine-induced polyclonal RH5 IgGs. These results suggest that pre-existing antibodies will interact favorably with vaccine-induced RH5 antibodies, in contrast to AMA1 antibodies. This study supports RH5 vaccine trials in malaria-endemic regions. RH5 IgG titers induced by infection are lower than those induced by RH5 vaccination Infection- and vaccine-induced RH5 IgGs have different specificity and avidity Infection- and vaccine-induced RH5 IgGs interact differently with RH5 mAbs Infection-induced IgGs generally do not reduce the activity of vaccine-induced IgGs
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Affiliation(s)
- Alexandra C Willcox
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Alex S Huber
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Ababacar Diouf
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Jordan R Barrett
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford OX3 7DQ, United Kingdom
| | - Sarah E Silk
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford OX3 7DQ, United Kingdom
| | - David Pulido
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford OX3 7DQ, United Kingdom
| | - Lloyd D W King
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford OX3 7DQ, United Kingdom
| | - Daniel G W Alanine
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford OX3 7DQ, United Kingdom
| | - Angela M Minassian
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford OX3 7DQ, United Kingdom
| | - Mahamadou Diakite
- Malaria Research and Training Center, Faculty of Medicine, Pharmacy, and Odontostomatology, University of Sciences, Techniques, and Technologies of Bamako, Bamako 1805, Mali
| | - Simon J Draper
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford OX3 7DQ, United Kingdom
| | - Carole A Long
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Kazutoyo Miura
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
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Bailey JA, Berry AA, Travassos MA, Ouattara A, Boudova S, Dotsey EY, Pike A, Jacob CG, Adams M, Tan JC, Bannen RM, Patel JJ, Pablo J, Nakajima R, Jasinskas A, Dutta S, Takala-Harrison S, Lyke KE, Laurens MB, Niangaly A, Coulibaly D, Kouriba B, Doumbo OK, Thera MA, Felgner PL, Plowe CV. Microarray analyses reveal strain-specific antibody responses to Plasmodium falciparum apical membrane antigen 1 variants following natural infection and vaccination. Sci Rep 2020; 10:3952. [PMID: 32127565 PMCID: PMC7054363 DOI: 10.1038/s41598-020-60551-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 02/13/2020] [Indexed: 11/30/2022] Open
Abstract
Vaccines based on Plasmodium falciparum apical membrane antigen 1 (AMA1) have failed due to extensive polymorphism in AMA1. To assess the strain-specificity of antibody responses to malaria infection and AMA1 vaccination, we designed protein and peptide microarrays representing hundreds of unique AMA1 variants. Following clinical malaria episodes, children had short-lived, sequence-independent increases in average whole-protein seroreactivity, as well as strain-specific responses to peptides representing diverse epitopes. Vaccination resulted in dramatically increased seroreactivity to all 263 AMA1 whole-protein variants. High-density peptide analysis revealed that vaccinated children had increases in seroreactivity to four distinct epitopes that exceeded responses to natural infection. A single amino acid change was critical to seroreactivity to peptides in a region of AMA1 associated with strain-specific vaccine efficacy. Antibody measurements using whole antigens may be biased towards conserved, immunodominant epitopes. Peptide microarrays may help to identify immunogenic epitopes, define correlates of vaccine protection, and measure strain-specific vaccine-induced antibodies.
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Affiliation(s)
- Jason A Bailey
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Andrea A Berry
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Mark A Travassos
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Amed Ouattara
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Sarah Boudova
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Emmanuel Y Dotsey
- Department of Physiology & Biophysics, University of California, Irvine, CA, USA
| | - Andrew Pike
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
| | | | - Matthew Adams
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
| | - John C Tan
- Previous address: Roche Sequencing Solutions, Madison, WI, USA
- Nimble Therapeutics, Madison, WI, USA
| | - Ryan M Bannen
- Previous address: Roche Sequencing Solutions, Madison, WI, USA
- Nimble Therapeutics, Madison, WI, USA
| | - Jigar J Patel
- Previous address: Roche Sequencing Solutions, Madison, WI, USA
- Nimble Therapeutics, Madison, WI, USA
| | - Jozelyn Pablo
- Department of Physiology & Biophysics, University of California, Irvine, CA, USA
| | - Rie Nakajima
- Department of Physiology & Biophysics, University of California, Irvine, CA, USA
| | - Algis Jasinskas
- Department of Physiology & Biophysics, University of California, Irvine, CA, USA
| | - Sheetij Dutta
- U.S. Military Malaria Vaccine Program, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Shannon Takala-Harrison
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Kirsten E Lyke
- 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
| | - Amadou Niangaly
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Drissa Coulibaly
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Bourema Kouriba
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Ogobara K Doumbo
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Mahamadou A Thera
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Philip L Felgner
- Department of Physiology & Biophysics, University of California, Irvine, CA, USA
| | - 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, Durham, NC, USA.
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Abstract
There have been significant decreases in malaria mortality and morbidity in the last 10-15 years, and the most advanced pre-erythrocytic malaria vaccine, RTS,S, received a positive opinion from European regulators in July 2015. However, no blood-stage vaccine has reached a phase III trial. The first part of this review summarizes the pros and cons of various assays and models that have been and will be used to predict the efficacy of blood-stage vaccines. In the second part, blood-stage vaccine candidates that showed some efficacy in human clinical trials or controlled human malaria infection models are discussed. Then, candidates under clinical investigation are described in the third part, and other novel candidates and strategies are reviewed in the last part.
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Affiliation(s)
- Kazutoyo Miura
- a Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases , National Institutes of Health , Rockville , MD , USA
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5
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Beeson JG, Drew DR, Boyle MJ, Feng G, Fowkes FJI, Richards JS. Merozoite surface proteins in red blood cell invasion, immunity and vaccines against malaria. FEMS Microbiol Rev 2016; 40:343-72. [PMID: 26833236 PMCID: PMC4852283 DOI: 10.1093/femsre/fuw001] [Citation(s) in RCA: 225] [Impact Index Per Article: 28.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/03/2016] [Indexed: 01/11/2023] Open
Abstract
Malaria accounts for an enormous burden of disease globally, with Plasmodium falciparum accounting for the majority of malaria, and P. vivax being a second important cause, especially in Asia, the Americas and the Pacific. During infection with Plasmodium spp., the merozoite form of the parasite invades red blood cells and replicates inside them. It is during the blood-stage of infection that malaria disease occurs and, therefore, understanding merozoite invasion, host immune responses to merozoite surface antigens, and targeting merozoite surface proteins and invasion ligands by novel vaccines and therapeutics have been important areas of research. Merozoite invasion involves multiple interactions and events, and substantial processing of merozoite surface proteins occurs before, during and after invasion. The merozoite surface is highly complex, presenting a multitude of antigens to the immune system. This complexity has proved challenging to our efforts to understand merozoite invasion and malaria immunity, and to developing merozoite antigens as malaria vaccines. In recent years, there has been major progress in this field, and several merozoite surface proteins show strong potential as malaria vaccines. Our current knowledge on this topic is reviewed, highlighting recent advances and research priorities. The authors summarize current knowledge of merozoite surface proteins of malaria parasites; their function in invasion, processing of surface proteins before, during and after invasion, their importance as targets of immunity, and the current status of malaria vaccines that target merozoite surface proteins.
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Affiliation(s)
- James G Beeson
- Burnet Institute for Medical Research and Public Health, 85 Commercial Road, Melbourne, Victoria, Australia Department of Microbiology, Monash University, Clayton, Victoria, Australia Department of Medicine, University of Melbourne, Parkville, Victoria, Australia
| | - Damien R Drew
- Burnet Institute for Medical Research and Public Health, 85 Commercial Road, Melbourne, Victoria, Australia
| | - Michelle J Boyle
- Burnet Institute for Medical Research and Public Health, 85 Commercial Road, Melbourne, Victoria, Australia
| | - Gaoqian Feng
- Burnet Institute for Medical Research and Public Health, 85 Commercial Road, Melbourne, Victoria, Australia
| | - Freya J I Fowkes
- Burnet Institute for Medical Research and Public Health, 85 Commercial Road, Melbourne, Victoria, Australia Department of Epidemiology and Preventive Medicine, Monash University, Clayton, Victoria, Australia School of Population Health, University of Melbourne, Parkville, Victoria, Australia
| | - Jack S Richards
- Burnet Institute for Medical Research and Public Health, 85 Commercial Road, Melbourne, Victoria, Australia Department of Microbiology, Monash University, Clayton, Victoria, Australia Department of Medicine, University of Melbourne, Parkville, Victoria, Australia
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Assessment of humoral immune responses to blood-stage malaria antigens following ChAd63-MVA immunization, controlled human malaria infection and natural exposure. PLoS One 2014; 9:e107903. [PMID: 25254500 PMCID: PMC4177865 DOI: 10.1371/journal.pone.0107903] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2014] [Accepted: 08/17/2014] [Indexed: 11/19/2022] Open
Abstract
The development of protective vaccines against many difficult infectious pathogens will necessitate the induction of effective antibody responses. Here we assess humoral immune responses against two antigens from the blood-stage merozoite of the Plasmodium falciparum human malaria parasite--MSP1 and AMA1. These antigens were delivered to healthy malaria-naïve adult volunteers in Phase Ia clinical trials using recombinant replication-deficient viral vectors--ChAd63 to prime the immune response and MVA to boost. In subsequent Phase IIa clinical trials, immunized volunteers underwent controlled human malaria infection (CHMI) with P. falciparum to assess vaccine efficacy, whereby all but one volunteer developed low-density blood-stage parasitemia. Here we assess serum antibody responses against both the MSP1 and AMA1 antigens following i) ChAd63-MVA immunization, ii) immunization and CHMI, and iii) primary malaria exposure in the context of CHMI in unimmunized control volunteers. Responses were also assessed in a cohort of naturally-immune Kenyan adults to provide comparison with those induced by a lifetime of natural malaria exposure. Serum antibody responses against MSP1 and AMA1 were characterized in terms of i) total IgG responses before and after CHMI, ii) responses to allelic variants of MSP1 and AMA1, iii) functional growth inhibitory activity (GIA), iv) IgG avidity, and v) isotype responses (IgG1-4, IgA and IgM). These data provide the first in-depth assessment of the quality of adenovirus-MVA vaccine-induced antibody responses in humans, along with assessment of how these responses are modulated by subsequent low-density parasite exposure. Notable differences were observed in qualitative aspects of the human antibody responses against these malaria antigens depending on the means of their induction and/or exposure of the host to the malaria parasite. Given the continued clinical development of viral vectored vaccines for malaria and a range of other diseases targets, these data should help to guide further immuno-monitoring studies of vaccine-induced human antibody responses.
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7
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Hodgson SH, Choudhary P, Elias SC, Milne KH, Rampling TW, Biswas S, Poulton ID, Miura K, Douglas AD, Alanine DG, Illingworth JJ, de Cassan SC, Zhu D, Nicosia A, Long CA, Moyle S, Berrie E, Lawrie AM, Wu Y, Ellis RD, Hill AVS, Draper SJ. Combining viral vectored and protein-in-adjuvant vaccines against the blood-stage malaria antigen AMA1: report on a phase 1a clinical trial. Mol Ther 2014; 22:2142-2154. [PMID: 25156127 PMCID: PMC4250079 DOI: 10.1038/mt.2014.157] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Accepted: 08/05/2014] [Indexed: 12/21/2022] Open
Abstract
The development of effective vaccines against difficult disease targets will require the identification of new subunit vaccination strategies that can induce and maintain effective immune responses in humans. Here we report on a phase 1a clinical trial using the AMA1 antigen from the blood-stage Plasmodium falciparum malaria parasite delivered either as recombinant protein formulated with Alhydrogel adjuvant with and without CPG 7909, or using recombinant vectored vaccines—chimpanzee adenovirus ChAd63 and the orthopoxvirus MVA. A variety of promising “mixed-modality” regimens were tested. All volunteers were primed with ChAd63, and then subsequently boosted with MVA and/or protein-in-adjuvant using either an 8- or 16-week prime-boost interval. We report on the safety of these regimens, as well as the T cell, B cell, and serum antibody responses. Notably, IgG antibody responses primed by ChAd63 were comparably boosted by AMA1 protein vaccine, irrespective of whether CPG 7909 was included in the Alhydrogel adjuvant. The ability to improve the potency of a relatively weak aluminium-based adjuvant in humans, by previously priming with an adenoviral vaccine vector encoding the same antigen, thus offers a novel vaccination strategy for difficult or neglected disease targets when access to more potent adjuvants is not possible.
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Affiliation(s)
- Susanne H Hodgson
- The Jenner Institute Laboratories, University of Oxford, Oxford, UK; Centre for Clinical Vaccinology and Tropical Medicine, The Jenner Institute, University of Oxford, Churchill Hospital, Oxford, UK.
| | | | - Sean C Elias
- The Jenner Institute Laboratories, University of Oxford, Oxford, UK
| | - Kathryn H Milne
- The Jenner Institute Laboratories, University of Oxford, Oxford, UK
| | - Thomas W Rampling
- The Jenner Institute Laboratories, University of Oxford, Oxford, UK; Centre for Clinical Vaccinology and Tropical Medicine, The Jenner Institute, University of Oxford, Churchill Hospital, Oxford, UK
| | - Sumi Biswas
- The Jenner Institute Laboratories, University of Oxford, Oxford, UK
| | - Ian D Poulton
- Centre for Clinical Vaccinology and Tropical Medicine, The Jenner Institute, University of Oxford, Churchill Hospital, Oxford, UK
| | - Kazutoyo Miura
- Laboratory of Malaria and Vector Research, NIAID/NIH, Rockville, Maryland, USA
| | | | | | | | | | - Daming Zhu
- Laboratory of Malaria and Vector Research, NIAID/NIH, Rockville, Maryland, USA
| | - Alfredo Nicosia
- Okairòs, Rome, Italy; CEINGE, Naples, Italy; Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy
| | - Carole A Long
- Laboratory of Malaria and Vector Research, NIAID/NIH, Rockville, Maryland, USA
| | - Sarah Moyle
- Clinical Biomanufacturing Facility, University of Oxford, Churchill Hospital, Oxford, UK
| | - Eleanor Berrie
- Clinical Biomanufacturing Facility, University of Oxford, Churchill Hospital, Oxford, UK
| | - Alison M Lawrie
- Centre for Clinical Vaccinology and Tropical Medicine, The Jenner Institute, University of Oxford, Churchill Hospital, Oxford, UK
| | - Yimin Wu
- Laboratory of Malaria Immunology and Vaccinology, NIAID/NIH, Rockville, Maryland, USA
| | - Ruth D Ellis
- Laboratory of Malaria Immunology and Vaccinology, NIAID/NIH, Rockville, Maryland, USA
| | - Adrian V S Hill
- The Jenner Institute Laboratories, University of Oxford, Oxford, UK
| | - Simon J Draper
- The Jenner Institute Laboratories, University of Oxford, Oxford, UK
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Osier FH, Mackinnon MJ, Crosnier C, Fegan G, Kamuyu G, Wanaguru M, Ogada E, McDade B, Rayner JC, Wright GJ, Marsh K. New antigens for a multicomponent blood-stage malaria vaccine. Sci Transl Med 2014; 6:247ra102. [PMID: 25080477 PMCID: PMC4856877 DOI: 10.1126/scitranslmed.3008705] [Citation(s) in RCA: 134] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
An effective blood-stage vaccine against Plasmodium falciparum remains a research priority, but the number of antigens that have been translated into multicomponent vaccines for testing in clinical trials remains limited. Investigating the large number of potential targets found in the parasite proteome has been constrained by an inability to produce natively folded recombinant antigens for immunological studies. We overcame these constraints by generating a large library of biochemically active merozoite surface and secreted full-length ectodomain proteins. We then systematically examined the antibody reactivity against these proteins in a cohort of Kenyan children (n = 286) who were sampled at the start of a malaria transmission season and prospectively monitored for clinical episodes of malaria over the ensuing 6 months. We found that antibodies to previously untested or little-studied proteins had superior or equivalent potential protective efficacy to the handful of current leading malaria vaccine candidates. Moreover, cumulative responses to combinations comprising 5 of the 10 top-ranked antigens, including PF3D7_1136200, MSP2, RhopH3, P41, MSP11, MSP3, PF3D7_0606800, AMA1, Pf113, and MSRP1, were associated with 100% protection against clinical episodes of malaria. These data suggest not only that there are many more potential antigen candidates for the malaria vaccine development pipeline but also that effective vaccination may be achieved by combining a selection of these antigens.
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MESH Headings
- Age Factors
- Antibodies, Protozoan/blood
- Antigens, Protozoan/immunology
- Biomarkers/blood
- Child
- Child, Preschool
- Humans
- Infant
- Infant, Newborn
- Kenya/epidemiology
- Malaria Vaccines/immunology
- Malaria, Falciparum/blood
- Malaria, Falciparum/epidemiology
- Malaria, Falciparum/immunology
- Malaria, Falciparum/parasitology
- Malaria, Falciparum/prevention & control
- Malaria, Falciparum/transmission
- Merozoites/immunology
- Peptide Fragments/immunology
- Plasmodium falciparum/immunology
- Prospective Studies
- Protozoan Proteins/immunology
- Seroepidemiologic Studies
- Time Factors
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Affiliation(s)
- Faith H Osier
- Pathogen Vector and Human Biology Department, Kenya Medical Research Institute Centre for Geographical Medicine Research, Coast, P. O. Box 230, 80108 Kilifi, Kenya
| | - Margaret J Mackinnon
- Pathogen Vector and Human Biology Department, Kenya Medical Research Institute Centre for Geographical Medicine Research, Coast, P. O. Box 230, 80108 Kilifi, Kenya
| | - Cécile Crosnier
- Cell Surface Signalling Laboratory, Wellcome Trust Sanger Institute, Cambridge CB10 1HH, UK. Malaria Programme, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, UK
| | - Gregory Fegan
- Pathogen Vector and Human Biology Department, Kenya Medical Research Institute Centre for Geographical Medicine Research, Coast, P. O. Box 230, 80108 Kilifi, Kenya
| | - Gathoni Kamuyu
- Pathogen Vector and Human Biology Department, Kenya Medical Research Institute Centre for Geographical Medicine Research, Coast, P. O. Box 230, 80108 Kilifi, Kenya
| | - Madushi Wanaguru
- Cell Surface Signalling Laboratory, Wellcome Trust Sanger Institute, Cambridge CB10 1HH, UK. Malaria Programme, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, UK
| | - Edna Ogada
- Pathogen Vector and Human Biology Department, Kenya Medical Research Institute Centre for Geographical Medicine Research, Coast, P. O. Box 230, 80108 Kilifi, Kenya
| | - Brian McDade
- Cell Surface Signalling Laboratory, Wellcome Trust Sanger Institute, Cambridge CB10 1HH, UK
| | - Julian C Rayner
- Malaria Programme, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, UK
| | - Gavin J Wright
- Cell Surface Signalling Laboratory, Wellcome Trust Sanger Institute, Cambridge CB10 1HH, UK. Malaria Programme, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, UK
| | - Kevin Marsh
- Pathogen Vector and Human Biology Department, Kenya Medical Research Institute Centre for Geographical Medicine Research, Coast, P. O. Box 230, 80108 Kilifi, Kenya.
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Bergmann-Leitner ES, Duncan EH, Mease RM, Angov E. Impact of pre-existing MSP1(42)-allele specific immunity on potency of an erythrocytic Plasmodium falciparum vaccine. Malar J 2012; 11:315. [PMID: 22958482 PMCID: PMC3502560 DOI: 10.1186/1475-2875-11-315] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2012] [Accepted: 08/30/2012] [Indexed: 01/03/2023] Open
Abstract
Background MSP1 is the major surface protein on merozoites and a prime candidate for a blood stage malaria vaccine. Preclinical and seroepidemiological studies have implicated antibodies to MSP1 in protection against blood stage parasitaemia and/or reduced parasite densities, respectively. Malaria endemic areas have multiple strains of Plasmodium falciparum circulating at any given time, giving rise to complex immune responses, an issue which is generally not addressed in clinical trials conducted in non-endemic areas. A lack of understanding of the effect of pre-existing immunity to heterologous parasite strains may significantly contribute to vaccine failure in the field. The purpose of this study was to model the effect of pre-existing immunity to MSP142 on the immunogenicity of blood-stage malaria vaccines based on alternative MSP1 alleles. Methods Inbred and outbred mice were immunized with various recombinant P. falciparum MSP142 proteins that represent the two major alleles of MSP142, MAD20 (3D7) and Wellcome (K1, FVO). Humoral immune responses were analysed by ELISA and LuminexTM, and functional activity of induced MSP142-specific antibodies was assessed by growth inhibition assays. T-cell responses were characterized using ex vivo ELISpot assays. Results Analysis of the immune responses induced by various immunization regimens demonstrated a strong allele-specific response at the T cell level in both inbred and outbred mice. The success of heterologous regimens depended on the degree of homology of the N-terminal p33 portion of the MSP142, likely due to the fact that most T cell epitopes reside in this part of the molecule. Analysis of humoral immune responses revealed a marked cross-reactivity between the alleles. Functional analyses showed that some of the heterologous regimens induced antibodies with improved growth inhibitory activities. Conclusion The development of a more broadly efficacious MSP1 based vaccine may be hindered by clonally imprinted p33 responses mainly restricted at the T cell level. In this study, the homology of the p33 sequence between the clonally imprinted response and the vaccine allele determines the magnitude of vaccine induced responses.
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Affiliation(s)
- Elke S Bergmann-Leitner
- Malaria Vaccine Branch, US Military Malaria Vaccine Program, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA.
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10
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Duncan CJA, Hill AVS, Ellis RD. Can growth inhibition assays (GIA) predict blood-stage malaria vaccine efficacy? Hum Vaccin Immunother 2012; 8:706-14. [PMID: 22508415 DOI: 10.4161/hv.19712] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
An effective vaccine against P. falciparum malaria remains a global health priority. Blood-stage vaccines are an important component of this effort, with some indications of recent progress. However only a fraction of potential blood-stage antigens have been tested, highlighting a critical need for efficient down-selection strategies. Functional in vitro assays such as the growth/invasion inhibition assays (GIA) are widely used, but it is unclear whether GIA activity correlates with protection or predicts vaccine efficacy. While preliminary data in controlled human malaria infection (CHMI) studies indicate a possible association between in vitro and in vivo parasite growth rates, there have been conflicting results of immunoepidemiology studies, where associations with exposure rather than protection have been observed. In addition, GIA-interfering antibodies in vaccinated individuals from endemic regions may limit assay sensitivity in heavily malaria-exposed populations. More work is needed to establish the utility of GIA for blood-stage vaccine development.
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Miura K, Perera S, Brockley S, Zhou H, Aebig JA, Moretz SE, Miller LH, Doumbo OK, Sagara I, Dicko A, Ellis RD, Long CA. Non-apical membrane antigen 1 (AMA1) IgGs from Malian children interfere with functional activity of AMA1 IgGs as judged by growth inhibition assay. PLoS One 2011; 6:e20947. [PMID: 21695140 PMCID: PMC3113848 DOI: 10.1371/journal.pone.0020947] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2011] [Accepted: 05/13/2011] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Apical membrane antigen 1 (AMA1) is one of the best-studied blood-stage malaria vaccine candidates. When an AMA1 vaccine was tested in a malaria naïve population, it induced functionally active antibodies judged by Growth Inhibition Assay (GIA). However, the same vaccine failed to induce higher growth-inhibitory activity in adults living in a malaria endemic area. Vaccination did induce functionally active antibodies in malaria-exposed children with less than 20% inhibition in GIA at baseline, but not in children with more than that level of baseline inhibition. METHODS Total IgGs were purified from plasmas collected from the pediatric trial before and after immunization and pools of total IgGs were made. Another set of total IgGs was purified from U.S. adults immunized with AMA1 (US-total IgG). From these total IgGs, AMA1-specific and non-AMA1 IgGs were affinity purified and the functional activity of these IgGs was evaluated by GIA. Competition ELISA was performed with the U.S.-total IgG and non-AMA1 IgGs from malaria-exposed children. RESULTS AMA1-specific IgGs from malaria-exposed children and U.S. vaccinees showed similar growth-inhibitory activity at the same concentrations. When mixed with U.S.-total IgG, non-AMA1 IgGs from children showed an interference effect in GIA. Interestingly, the interference effect was higher with non-AMA1 IgGs from higher titer pools. The non-AMA1 IgGs did not compete with anti-AMA1 antibody in U.S.-total IgG in the competition ELISA. CONCLUSION Children living in a malaria endemic area have a fraction of IgGs that interferes with the biological activity of anti-AMA1 antibody as judged by GIA. While the mechanism of interference is not resolved in this study, these results suggest it is not caused by direct competition between non-AMA1 IgG and AMA1 protein. This study indicates that anti-malaria IgGs induced by natural exposure may interfere with the biological effect of antibody induced by an AMA1-based vaccine in the target population.
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Affiliation(s)
- Kazutoyo Miura
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
- * E-mail: (KM); (CAL)
| | - Suwani Perera
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Sarah Brockley
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Hong Zhou
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Joan A. Aebig
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Samuel E. Moretz
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Louis H. Miller
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Ogobara K. Doumbo
- Malaria Research and Training Center, Faculty of Medicine Pharmacy and Dentistry, University of Bamako, Bamako, Mali
| | - Issaka Sagara
- Malaria Research and Training Center, Faculty of Medicine Pharmacy and Dentistry, University of Bamako, Bamako, Mali
| | - Alassane Dicko
- Malaria Research and Training Center, Faculty of Medicine Pharmacy and Dentistry, University of Bamako, Bamako, Mali
| | - Ruth D. Ellis
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Carole A. Long
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
- * E-mail: (KM); (CAL)
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