1
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Persson KEM, Horton JL, Kurtovic L, McCarthy JS, Anders RF, Beeson JG. Declining Antibody Affinity Over Time After Human Vaccination With a Plasmodium falciparum Merozoite Vaccine Candidate. J Infect Dis 2024; 230:e753-e757. [PMID: 38723177 PMCID: PMC11420798 DOI: 10.1093/infdis/jiae259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Accepted: 05/08/2024] [Indexed: 09/25/2024] Open
Abstract
Maintaining high-affinity antibodies after vaccination may be important for long-lasting immunity to malaria, but data on induction and kinetics of affinity is lacking. In a phase 1 malaria vaccine trial, antibody affinity increased following a second vaccination but declined substantially over 12 months, suggesting poor maintenance of high-affinity antibodies. CLINICAL TRIALS REGISTRATION Australian New Zealand Clinical Trials Registry ACTRN12607000552482.
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Affiliation(s)
- Kristina E M Persson
- Department of Laboratory Medicine, Lund University, Lund, Sweden
- Department of Clinical Chemistry and Pharmacology, Laboratory Medicine, Region Skåne, Lund, Sweden
| | | | | | - James S McCarthy
- QIMR-Berghofer Medical Research Institute, QueenslandAustralia
- Victorian Infectious Diseases Services, Doherty Institute, University of Melbourne, Melbourne, Victoria, Australia
| | - Robin F Anders
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Sciences, La Trobe University, Bundoora, Victoria, Australia
| | - James G Beeson
- Burnet Institute, Melbourne, Victoria, Australia
- Central Clinical School and Department of Microbiology, Monash University, Melbourne, Victoria, Australia
- Department of Infectious Diseases, University of Melbourne, Melbourne, Victoria, Australia
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2
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Boyle MJ, Engwerda CR, Jagannathan P. The impact of Plasmodium-driven immunoregulatory networks on immunity to malaria. Nat Rev Immunol 2024; 24:637-653. [PMID: 38862638 DOI: 10.1038/s41577-024-01041-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/30/2024] [Indexed: 06/13/2024]
Abstract
Malaria, caused by infection with Plasmodium parasites, drives multiple regulatory responses across the immune landscape. These regulatory responses help to protect against inflammatory disease but may in some situations hamper the acquisition of adaptive immune responses that clear parasites. In addition, the regulatory responses that occur during Plasmodium infection may negatively affect malaria vaccine efficacy in the most at-risk populations. Here, we discuss the specific cellular mechanisms of immunoregulatory networks that develop during malaria, with a focus on knowledge gained from human studies and studies that involve the main malaria parasite to affect humans, Plasmodium falciparum. Leveraging this knowledge may lead to the development of new therapeutic approaches to increase protective immunity to malaria during infection or after vaccination.
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Affiliation(s)
- Michelle J Boyle
- Life Sciences Division, Burnet Institute, Melbourne, Victoria, Australia.
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia.
| | | | - Prasanna Jagannathan
- Department of Medicine, Stanford University, Stanford, CA, USA.
- Department of Microbiology and Immunology, Stanford University, Stanford, CA, USA.
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3
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Rosenkranz M, Nkumama IN, Ogwang R, Kraker S, Blickling M, Mwai K, Odera D, Tuju J, Fürle K, Frank R, Chepsat E, Kapulu MC, Study Team CS, Osier FH. Full-length MSP1 is a major target of protective immunity after controlled human malaria infection. Life Sci Alliance 2024; 7:e202301910. [PMID: 38803222 PMCID: PMC11106525 DOI: 10.26508/lsa.202301910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Revised: 05/08/2024] [Accepted: 05/08/2024] [Indexed: 05/29/2024] Open
Abstract
The merozoite surface protein 1 (MSP1) is the most abundant protein on the surface of the invasive merozoite stages of Plasmodium falciparum and has long been considered a key target of protective immunity. We used samples from a single controlled human malaria challenge study to test whether the full-length version of MSP1 (MSP1FL) induced antibodies that mediated Fc-IgG functional activity in five independent assays. We found that anti-MSP1FL antibodies induced complement fixation via C1q, monocyte-mediated phagocytosis, neutrophil respiratory burst, and natural killer cell degranulation as well as IFNγ production. Activity in each of these assays was strongly associated with protection. The breadth of MSP1-specific Fc-mediated effector functions was more strongly associated with protection than the individual measures and closely mirrored what we have previously reported using the same assays against merozoites. Our findings suggest that MSP1FL is an important target of functional antibodies that contribute to a protective immune response against malaria.
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Affiliation(s)
- Micha Rosenkranz
- https://ror.org/013czdx64 Centre of Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | - Irene N Nkumama
- B Cell Immunology, German Cancer Research Centre, Heidelberg, Germany
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Rodney Ogwang
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Sara Kraker
- https://ror.org/013czdx64 Centre of Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | - Marie Blickling
- https://ror.org/013czdx64 Centre of Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | - Kennedy Mwai
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya
- Epidemiology and Biostatistics Division, School of Public Health, University of the Witwatersrand, Johannesburg, South Africa
| | - Dennis Odera
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya
| | - James Tuju
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya
- Department of Biotechnology and Biochemistry, Pwani University, Kilifi, Kenya
| | - Kristin Fürle
- https://ror.org/013czdx64 Centre of Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | - Roland Frank
- https://ror.org/013czdx64 Centre of Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | - Emily Chepsat
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Melissa C Kapulu
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Chmi-Sika Study Team
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Faith Ha Osier
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya
- https://ror.org/041kmwe10 Department of Life Sciences, Imperial College London, London, UK
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4
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Nkumama IN, Ogwang R, Odera D, Musasia F, Mwai K, Nyamako L, Murungi L, Tuju J, Fürle K, Rosenkranz M, Kimathi R, Njuguna P, Hamaluba M, Kapulu MC, Frank R, Osier FHA. Breadth of Fc-mediated effector function correlates with clinical immunity following human malaria challenge. Immunity 2024; 57:1215-1224.e6. [PMID: 38788711 DOI: 10.1016/j.immuni.2024.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 03/19/2024] [Accepted: 05/01/2024] [Indexed: 05/26/2024]
Abstract
Malaria is a life-threatening disease of global health importance, particularly in sub-Saharan Africa. The growth inhibition assay (GIA) is routinely used to evaluate, prioritize, and quantify the efficacy of malaria blood-stage vaccine candidates but does not reliably predict either naturally acquired or vaccine-induced protection. Controlled human malaria challenge studies in semi-immune volunteers provide an unparalleled opportunity to robustly identify mechanistic correlates of protection. We leveraged this platform to undertake a head-to-head comparison of seven functional antibody assays that are relevant to immunity against the erythrocytic merozoite stage of Plasmodium falciparum. Fc-mediated effector functions were strongly associated with protection from clinical symptoms of malaria and exponential parasite multiplication, while the gold standard GIA was not. The breadth of Fc-mediated effector function discriminated clinical immunity following the challenge. These findings present a shift in the understanding of the mechanisms that underpin immunity to malaria and have important implications for vaccine development.
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Affiliation(s)
- Irene N Nkumama
- Centre of Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany; Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute, Wellcome Trust Research Programme, Kilifi, Kenya; European Vaccine Initiative, Heidelberg, Germany
| | - Rodney Ogwang
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute, Wellcome Trust Research Programme, Kilifi, Kenya
| | - Dennis Odera
- Centre of Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany; Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute, Wellcome Trust Research Programme, Kilifi, Kenya
| | - Fauzia Musasia
- Centre of Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | - Kennedy Mwai
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute, Wellcome Trust Research Programme, Kilifi, Kenya; Epidemiology and Biostatistics Division, School of Public Health, University of the Witwatersrand, Johannesburg, South Africa
| | - Lydia Nyamako
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute, Wellcome Trust Research Programme, Kilifi, Kenya
| | - Linda Murungi
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute, Wellcome Trust Research Programme, Kilifi, Kenya
| | - James Tuju
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute, Wellcome Trust Research Programme, Kilifi, Kenya; Department of Biotechnology and Biochemistry, Pwani University, Kilifi, Kenya
| | - Kristin Fürle
- Centre of Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | - Micha Rosenkranz
- Centre of Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | - Rinter Kimathi
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute, Wellcome Trust Research Programme, Kilifi, Kenya
| | - Patricia Njuguna
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute, Wellcome Trust Research Programme, Kilifi, Kenya
| | - Mainga Hamaluba
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute, Wellcome Trust Research Programme, Kilifi, Kenya
| | - Melissa C Kapulu
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute, Wellcome Trust Research Programme, Kilifi, Kenya
| | - Roland Frank
- Centre of Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | - Faith H A Osier
- Centre of Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany; Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute, Wellcome Trust Research Programme, Kilifi, Kenya; Department of Life Sciences, Imperial College London, London, UK.
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5
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Miura K. How to Accelerate Early Stage of Malaria Vaccine Development by Optimizing Functional Assays. Vaccines (Basel) 2024; 12:586. [PMID: 38932315 PMCID: PMC11209467 DOI: 10.3390/vaccines12060586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2024] [Revised: 05/23/2024] [Accepted: 05/24/2024] [Indexed: 06/28/2024] Open
Abstract
While two Plasmodium falciparum circumsporozoite protein-based pre-erythrocytic vaccines (PEV), RTS,S and R21, have been approved by the WHO, no blood-stage vaccine (BSV) or transmission-blocking vaccine (TBV) has reached a phase 3 trial. One of the major obstacles that slows down malaria vaccine development is the shortage (or lack) of in vitro assays or animal models by which investigators can reasonably select the best vaccine formulation (e.g., antigen, adjuvant, or platform) and/or immunization strategy (e.g., interval of inoculation or route of immunization) before a human phase 2 trial. In the case of PEV, RTS,S and R21 have set a benchmark, and a new vaccine can be compared with (one of) the approved PEV directly in preclinical or early clinical studies. However, such an approach cannot be utilized for BSV or TBV development at this moment. The focus of this review is in vitro assays or in vivo models that can be used for P. falciparum BSV or TBV development, and I discuss important considerations during assay selection, standardization, qualification, validation, and interpretation of the assay results. Establishment of a robust assay/model with proper interpretation of the results is the one of key elements to accelerate future vaccine development.
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Affiliation(s)
- 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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6
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Martinez FJ, White M, Guillotte-Blisnick M, Huon C, Boucharlat A, Agou F, England P, Popovici J, Hou MM, Silk SE, Barrett JR, Nielsen CM, Reimer JM, Mukherjee P, Chauhan VS, Minassian AM, Draper SJ, Chitnis CE. PvDBPII elicits multiple antibody-mediated mechanisms that reduce growth in a Plasmodium vivax challenge trial. NPJ Vaccines 2024; 9:10. [PMID: 38184681 PMCID: PMC10771494 DOI: 10.1038/s41541-023-00796-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Accepted: 12/07/2023] [Indexed: 01/08/2024] Open
Abstract
The receptor-binding domain, region II, of the Plasmodium vivax Duffy binding protein (PvDBPII) binds the Duffy antigen on the reticulocyte surface to mediate invasion. A heterologous vaccine challenge trial recently showed that a delayed dosing regimen with recombinant PvDBPII SalI variant formulated with adjuvant Matrix-MTM reduced the in vivo parasite multiplication rate (PMR) in immunized volunteers challenged with the Thai P. vivax isolate PvW1. Here, we describe extensive analysis of the polyfunctional antibody responses elicited by PvDBPII immunization and identify immune correlates for PMR reduction. A classification algorithm identified antibody features that significantly contribute to PMR reduction. These included antibody titre, receptor-binding inhibitory titre, dissociation constant of the PvDBPII-antibody interaction, complement C1q and Fc gamma receptor binding and specific IgG subclasses. These data suggest that multiple immune mechanisms elicited by PvDBPII immunization are likely to be associated with protection and the immune correlates identified could guide the development of an effective vaccine for P. vivax malaria. Importantly, all the polyfunctional antibody features that correlated with protection cross-reacted with both PvDBPII SalI and PvW1 variants, suggesting that immunization with PvDBPII should protect against diverse P. vivax isolates.
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Affiliation(s)
- Francisco J Martinez
- Unité de Biologie de Plasmodium et Vaccins, Institut Pasteur, Université Paris Cité, Paris, France
| | - Michael White
- Infectious Disease Epidemiology and Analytics G5 Unit, Institut Pasteur, Université Paris Cité, Paris, France
| | | | - Christèle Huon
- Unité de Biologie de Plasmodium et Vaccins, Institut Pasteur, Université Paris Cité, Paris, France
| | - Alix Boucharlat
- Chemogenomic and Biological Screening Core Facility, C2RT, Institut Pasteur, Université Paris Cité, CNRS UMR 3523, Paris, France
| | - Fabrice Agou
- Chemogenomic and Biological Screening Core Facility, C2RT, Institut Pasteur, Université Paris Cité, CNRS UMR 3523, Paris, France
| | - Patrick England
- Molecular Biophysics Facility, CNRS UMR 3528, Institut Pasteur, Paris, France
| | - Jean Popovici
- Malaria Reasearch Unit, Institut Pasteur du Cambodge, Pnom Penh, Cambodia
| | - Mimi M Hou
- Department of Biochemistry, University of Oxford, Oxford, OX1 3QU, UK
- The Jenner Institute, University of Oxford, Oxford, OX3 7DQ, UK
- Kavli Institute for Nanoscience Discovery, University of Oxford, Oxford, OX1 3QU, UK
| | - Sarah E Silk
- Department of Biochemistry, University of Oxford, Oxford, OX1 3QU, UK
- The Jenner Institute, University of Oxford, Oxford, OX3 7DQ, UK
- Kavli Institute for Nanoscience Discovery, University of Oxford, Oxford, OX1 3QU, UK
| | - Jordan R Barrett
- Department of Biochemistry, University of Oxford, Oxford, OX1 3QU, UK
- The Jenner Institute, University of Oxford, Oxford, OX3 7DQ, UK
- Kavli Institute for Nanoscience Discovery, University of Oxford, Oxford, OX1 3QU, UK
| | - Carolyn M Nielsen
- Department of Biochemistry, University of Oxford, Oxford, OX1 3QU, UK
- The Jenner Institute, University of Oxford, Oxford, OX3 7DQ, UK
- Kavli Institute for Nanoscience Discovery, University of Oxford, Oxford, OX1 3QU, UK
| | | | | | - Virander S Chauhan
- International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
| | - Angela M Minassian
- Department of Biochemistry, University of Oxford, Oxford, OX1 3QU, UK
- The Jenner Institute, University of Oxford, Oxford, OX3 7DQ, UK
- Kavli Institute for Nanoscience Discovery, University of Oxford, Oxford, OX1 3QU, UK
- NIHR Oxford Biomedical Research Centre, Oxford, UK
| | - Simon J Draper
- Department of Biochemistry, University of Oxford, Oxford, OX1 3QU, UK
- The Jenner Institute, University of Oxford, Oxford, OX3 7DQ, UK
- Kavli Institute for Nanoscience Discovery, University of Oxford, Oxford, OX1 3QU, UK
- NIHR Oxford Biomedical Research Centre, Oxford, UK
| | - Chetan E Chitnis
- Unité de Biologie de Plasmodium et Vaccins, Institut Pasteur, Université Paris Cité, Paris, France.
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7
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Thomson-Luque R, Stabler TC, Fürle K, Silva JC, Daubenberger C. Plasmodium falciparum merozoite surface protein 1 as asexual blood stage malaria vaccine candidate. Expert Rev Vaccines 2024; 23:160-173. [PMID: 38100310 DOI: 10.1080/14760584.2023.2295430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 12/12/2023] [Indexed: 12/17/2023]
Abstract
INTRODUCTION Malaria represents a public health challenge in tropical and subtropical regions, and currently deployed control strategies are likely insufficient to drive elimination of malaria. Development and improvement of malaria vaccines might be key to reduce disease burden. Vaccines targeting asexual blood stages of the parasite have shown limited efficacy when studied in human trials conducted over the past decades. AREAS COVERED Vaccine candidates based on the merozoite surface protein 1 (MSP1) were initially envisioned as one of the most promising approaches to provide immune protection against asexual blood-stage malaria. Successful immunization studies in monkey involved the use of the full-length MSP1 (MSP1FL) as vaccine construct. Vaccines using MSP1FL for immunization have the potential benefit of including numerous conserved B-cell and T-cell epitopes. This could result in improved parasite strain-transcending, protective immunity in the field. We review outcomes of clinical trials that utilized a variety of MSP1 constructs and formulations, including MSP1FL, either alone or in combination with other antigens, in both animal models and humans. EXPERT OPINION Novel approaches to analyze breadth and magnitude of effector functions of MSP1-targeting antibodies in volunteers undergoing experimental vaccination and controlled human malaria infection will help to define correlates of protective immunity.
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Affiliation(s)
- Richard Thomson-Luque
- Centre for Infectious Diseases-Parasitology, Heidelberg University Hospital, Heidelberg, Germany
- Sumaya-Biotech GmbH & Co. KG Heidelberg, Germany
| | - Thomas C Stabler
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
- University of Basel Basel, Switzerland
- Swiss Tropical and Public Health Institute Allschwil, Switzerland
| | - Kristin Fürle
- Centre for Infectious Diseases-Parasitology, Heidelberg University Hospital, Heidelberg, Germany
| | - Joana C Silva
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD, USA
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
- Global Health and Tropical Medicine, Instituto de Higiene e Medicina Tropical, Universidade NOVA de Lisboa (GHTM IHMT, UNL), Lisbon, Portugal
| | - Claudia Daubenberger
- University of Basel Basel, Switzerland
- Swiss Tropical and Public Health Institute Allschwil, Switzerland
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8
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Mortazavi SE, Lugaajju A, Nylander M, Danielsson L, Tijani MK, Beeson JG, Persson KEM. Acquisition of complement fixing antibodies targeting Plasmodium falciparum merozoites in infants and their mothers in Uganda. Front Immunol 2023; 14:1295543. [PMID: 38090561 PMCID: PMC10715273 DOI: 10.3389/fimmu.2023.1295543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2023] [Accepted: 11/10/2023] [Indexed: 12/18/2023] Open
Abstract
Background Antibody-mediated complement fixation has previously been associated with protection against malaria in naturally acquired immunity. However, the process of early-life development of complement-fixing antibodies in infants, both in comparison to their respective mothers and to other immune parameters, remains less clear. Results We measured complement-fixing antibodies in newborns and their mothers in a malaria endemic area over 5 years follow-up and found that infants' complement-fixing antibody levels were highest at birth, decreased until six months, then increased progressively until they were similar to birth at five years. Infants with high levels at birth experienced a faster decay of complement-fixing antibodies but showed similar levels to the low response group of newborns thereafter. No difference was observed in antibody levels between infant cord blood and mothers at delivery. The same result was found when categorized into high and low response groups, indicating placental transfer of antibodies. Complement-fixing antibodies were positively correlated with total schizont-specific IgG and IgM levels in mothers and infants at several time points. At nine months, complement-fixing antibodies were negatively correlated with total B cell frequency and osteopontin concentrations in the infants, while positively correlated with atypical memory B cells and P. falciparum-positive atypical memory B cells. Conclusion This study indicates that complement-fixing antibodies against P. falciparum merozoites are produced in the mothers and placentally-transferred, and they are acquired in infants over time during the first years of life. Understanding early life immune responses is crucial for developing a functional, long lasting malaria vaccine.
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Affiliation(s)
- Susanne E. Mortazavi
- Department of Laboratory Medicine, Lund University, Lund, Sweden
- Department of Infectious Diseases, Skåne University Hospital, Lund, Sweden
| | - Allan Lugaajju
- College of Health Sciences, Makerere University, Kampala, Uganda
| | - Maria Nylander
- Department of Laboratory Medicine, Lund University, Lund, Sweden
| | - Lena Danielsson
- Department of Laboratory Medicine, Lund University, Lund, Sweden
- Clinical Chemistry and Pharmacology, Laboratory Medicine, Office for Medical Services, Region Skåne, Lund, Sweden
| | - Muyideen Kolapo Tijani
- Department of Laboratory Medicine, Lund University, Lund, Sweden
- Cellular Parasitology Program, Cell Biology and Genetics Unit, Department of Zoology, University of Ibadan, Ibadan, Nigeria
| | - James G. Beeson
- The Burnet Institute, Melbourne, VIC, Australia
- Department of Infectious Diseases, University of Melbourne, Melbourne, VIC, Australia
- Central Clinical School and Department of Microbiology, Monash University, Melbourne, VIC, Australia
| | - Kristina E. M. Persson
- Department of Laboratory Medicine, Lund University, Lund, Sweden
- Clinical Chemistry and Pharmacology, Laboratory Medicine, Office for Medical Services, Region Skåne, Lund, Sweden
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9
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Rosenkranz M, Fürle K, Hibbert J, Ulmer A, Ali A, Giese T, Blank A, Haefeli WE, Böhnlein E, Lanzer M, Thomson-Luque R. Multifunctional IgG/IgM antibodies and cellular cytotoxicity are elicited by the full-length MSP1 SumayaVac-1 malaria vaccine. NPJ Vaccines 2023; 8:112. [PMID: 37558673 PMCID: PMC10412566 DOI: 10.1038/s41541-023-00701-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 06/27/2023] [Indexed: 08/11/2023] Open
Abstract
Radical control of malaria likely requires a vaccine that targets both the asymptomatic liver stages and the disease-causing blood stages of the human malaria parasite Plasmodium falciparum. While substantial progress has been made towards liver stage vaccines, the development of a blood stage vaccine is lagging behind. We have recently conducted a first-in-human clinical trial to evaluate the safety and immunogenicity of the recombinant, full-length merozoite surface protein 1 (MSP1FL) formulated with GLA-SE as adjuvant. Here, we show that the vaccine, termed SumayaVac-1, elicited both a humoral and cellular immune response as well as a recall T cell memory. The induced IgG and IgM antibodies were able to stimulate various Fc-mediated effector mechanisms associated with protection against malaria, including phagocytosis, release of reactive oxygen species, production of IFN-γ as well as complement activation and fixation. The multifunctional activity of the humoral immune response remained for at least 6 months after vaccination and was comparable to that of naturally acquired anti-MSP1 antibodies from semi-immune adults from Kenya. We further present evidence of SumayaVac-1 eliciting a recallable cellular cytotoxicity by IFN-γ producing CD8+ T cells. Our study revitalizes MSP1FL as a relevant blood stage vaccine candidate and warrants further evaluation of SumayaVac-1 in a phase II efficacy trial.
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Affiliation(s)
- Micha Rosenkranz
- Center for Infectious Diseases-Parasitology, Heidelberg University Hospital, Heidelberg, Germany
| | - Kristin Fürle
- Center for Infectious Diseases-Parasitology, Heidelberg University Hospital, Heidelberg, Germany
| | - Julia Hibbert
- Center for Infectious Diseases-Parasitology, Heidelberg University Hospital, Heidelberg, Germany
| | - Anne Ulmer
- Center for Infectious Diseases-Parasitology, Heidelberg University Hospital, Heidelberg, Germany
| | - Arin Ali
- Center for Infectious Diseases-Parasitology, Heidelberg University Hospital, Heidelberg, Germany
| | - Thomas Giese
- Institute for Immunology, Heidelberg University Hospital and German Center for Infection Research (DZIF), Heidelberg, Germany
| | - Antje Blank
- Clinical Pharmacology and Pharmacoepidemiology, Heidelberg University Hospital, Heidelberg, Germany
| | - Walter E Haefeli
- Clinical Pharmacology and Pharmacoepidemiology, Heidelberg University Hospital, Heidelberg, Germany
| | | | - Michael Lanzer
- Center for Infectious Diseases-Parasitology, Heidelberg University Hospital, Heidelberg, Germany
| | - Richard Thomson-Luque
- Center for Infectious Diseases-Parasitology, Heidelberg University Hospital, Heidelberg, Germany.
- Sumaya-Biotech GmbH & Co. KG, Heidelberg, Germany.
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10
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Defining species-specific and conserved interactions of apical membrane protein 1 during erythrocyte invasion in malaria to inform multi-species vaccines. Cell Mol Life Sci 2023; 80:74. [PMID: 36847896 PMCID: PMC9969379 DOI: 10.1007/s00018-023-04712-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 01/17/2023] [Accepted: 01/30/2023] [Indexed: 03/01/2023]
Abstract
Plasmodium falciparum and P. vivax are the major causes of human malaria, and P. knowlesi is an important additional cause in SE Asia. Binding of apical membrane antigen 1 (AMA1) to rhoptry neck protein 2 (RON2) was thought to be essential for merozoite invasion of erythrocytes by Plasmodium spp. Our findings reveal that P. falciparum and P. vivax have diverged and show species-specific binding of AMA1 to RON2, determined by a β-hairpin loop in RON2 and specific residues in AMA1 Loop1E. In contrast, cross-species binding of AMA1 to RON2 is retained between P. vivax and P. knowlesi. Mutation of specific amino acids in AMA1 Loop1E in P. falciparum or P. vivax ablated RON2 binding without impacting erythrocyte invasion. This indicates that the AMA1-RON2-loop interaction is not essential for invasion and additional AMA1 interactions are involved. Mutations in AMA1 that disrupt RON2 binding also enable escape of invasion inhibitory antibodies. Therefore, vaccines and therapeutics will need to be broader than targeting only the AMA1-RON2 interaction. Antibodies targeting AMA1 domain 3 had greater invasion-inhibitory activity when RON2-loop binding was ablated, suggesting this domain is a promising additional target for vaccine development. Targeting multiple AMA1 interactions involved in invasion may enable vaccines that generate more potent inhibitory antibodies and address the capacity for immune evasion. Findings on specific residues for invasion function and species divergence and conservation can inform novel vaccines and therapeutics against malaria caused by three species, including the potential for cross-species vaccines.
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11
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B-Cell Epitope Mapping of the Plasmodium falciparum Malaria Vaccine Candidate GMZ2.6c in a Naturally Exposed Population of the Brazilian Amazon. Vaccines (Basel) 2023; 11:vaccines11020446. [PMID: 36851323 PMCID: PMC9966924 DOI: 10.3390/vaccines11020446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 02/09/2023] [Accepted: 02/13/2023] [Indexed: 02/17/2023] Open
Abstract
The GMZ2.6c malaria vaccine candidate is a multi-stage P. falciparum chimeric protein that contains a fragment of the sexual-stage Pfs48/45-6C protein genetically fused to GMZ2, an asexual-stage vaccine construction consisting of the N-terminal region of the glutamate-rich protein (GLURP) and the C-terminal region of the merozoite surface protein-3 (MSP-3). Previous studies showed that GMZ2.6c is widely recognized by antibodies from Brazilian exposed individuals and that its components are immunogenic in natural infection by P. falciparum. In addition, anti-GMZ2.6c antibodies increase with exposure to infection and may contribute to parasite immunity. Therefore, identifying epitopes of proteins recognized by antibodies may be an important tool for understanding protective immunity. Herein, we identify and validate the B-cell epitopes of GMZ2.6c as immunogenic and immunodominant in individuals exposed to malaria living in endemic areas of the Brazilian Amazon. Specific IgG antibodies and subclasses against MSP-3, GLURP, and Pfs48/45 epitopes were detected by ELISA using synthetic peptides corresponding to B-cell epitopes previously described for MSP-3 and GLURP or identified by BepiPred for Pfs48/45. The results showed that the immunodominant epitopes were P11 from GLURP and MSP-3c and DG210 from MSP-3. The IgG1 and IgG3 subclasses were preferentially induced against these epitopes, supporting previous studies that these proteins are targets for cytophilic antibodies, important for the acquisition of protective immunity. Most individuals presented detectable IgG antibodies against Pfs48/45a and/or Pfs48/45b, validating the prediction of linear B-cell epitopes. The higher frequency and antibody levels against different epitopes from GLURP, MSP-3, and Pfs48/45 provide additional information that may suggest the relevance of GMZ2.6c as a multi-stage malaria vaccine candidate.
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12
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Odera DO, Tuju J, Mwai K, Nkumama IN, Fürle K, Chege T, Kimathi R, Diehl S, Musasia FK, Rosenkranz M, Njuguna P, Hamaluba M, Kapulu MC, Frank R, Osier FHA, Abdi AI, Chi PC, de Laurent Z, Jao I, Kamuya D, Kamuyu G, Makale J, Murungi L, Musyoki J, Muthui M, Mwacharo J, Kariuki S, Mwanga D, Mwongeli J, Ndungu F, Njue M, Nyangweso G, Kimani D, Ngoi JM, Musembi J, Ngoto O, Otieno E, Ooko M, Shangala J, Wambua J, Mohammed KS, Omuoyo D, Mosobo M, Kibinge N, Kinyanjui S, Bejon P, Lowe B, Marsh K, Marsh V, Abebe Y, Billingsley PF, Sim BKL, Hoffman SL, James ER, Richie TL, Audi A, Olewe F, Oloo J, Ongecha J, Ongas MO, Koskei N, Bull PC, Hodgson SH, Kivisi C, Imwong M, Murphy SC, Ogutu B, Tarning J, Winterberg M, Williams TN. Anti-merozoite antibodies induce natural killer cell effector function and are associated with immunity against malaria. Sci Transl Med 2023; 15:eabn5993. [PMID: 36753561 DOI: 10.1126/scitranslmed.abn5993] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
Natural killer (NK) cells are potent immune effectors that can be activated via antibody-mediated Fc receptor engagement. Using multiparameter flow cytometry, we found that NK cells degranulate and release IFN-γ upon stimulation with antibody-opsonized Plasmodium falciparum merozoites. Antibody-dependent NK (Ab-NK) activity was largely strain transcending and enhanced invasion inhibition into erythrocytes. Ab-NK was associated with the successful control of parasitemia after experimental malaria challenge in African adults. In an independent cohort study in children, Ab-NK increased with age, was boosted by concurrent P. falciparum infections, and was associated with a lower risk of clinical episodes of malaria. Nine of the 14 vaccine candidates tested induced Ab-NK, including some less well-characterized antigens: P41, P113, MSP11, RHOPH3, and Pf_11363200. These data highlight an important role of Ab-NK activity in immunity against malaria and provide a potential mechanism for evaluating vaccine candidates.
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Affiliation(s)
- Dennis O Odera
- Centre of Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany.,Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya
| | - James Tuju
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Kennedy Mwai
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya.,Epidemiology and Biostatistics Division, School of Public Health, University of the Witwatersrand, Johannesburg, South Africa
| | - Irene N Nkumama
- Centre of Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | - Kristin Fürle
- Centre of Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | - Timothy Chege
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Rinter Kimathi
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Stefan Diehl
- Centre of Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | - Fauzia K Musasia
- Centre of Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | - Micha Rosenkranz
- Centre of Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | - Patricia Njuguna
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Mainga Hamaluba
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Melissa C Kapulu
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Roland Frank
- Centre of Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | | | - Faith H A Osier
- Centre of Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany.,Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya.,Department of Life Sciences, Imperial College London, UK
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13
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Ngulube P. Humoral Immune Responses to P. falciparum Circumsporozoite Protein (Pfcsp) Induced by the RTS, S Vaccine - Current Update. Infect Drug Resist 2023; 16:2147-2157. [PMID: 37077252 PMCID: PMC10106824 DOI: 10.2147/idr.s401247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Accepted: 03/23/2023] [Indexed: 04/21/2023] Open
Abstract
Malaria vaccines targeting the circumsporozoite protein (CSP) of the P. falciparum parasite have been overall relatively promising. RTS, S is a pre-erythrocytic recombinant protein-based malaria vaccine that targets CSP. RTS, S effectiveness shows some limited success regardless of its 58% efficacy for severe disease. P. falciparum circumsporozoite protein (Pfcsp) has stood to be the main candidate protein for most pre-erythrocytic stage vaccines. Studies on the structural and biophysical characteristics of antibodies specific to CSP (anti-CSP) are underway to achieve fine specificity with the CSP polymorphic regions. More recent studies have proposed the use of different kinds of monoclonal antibodies, the use of appropriate adjuvants, ideal vaccination dose and frequency, and improved targeting of particular epitopes for the robust production of functional antibodies and high complement-fixing activity as other potential methods for achieving long-lasting RTS, S. This review highlights recent findings regarding humoral immune responses to CSP elicited by RTS, S vaccine.
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Affiliation(s)
- Peter Ngulube
- Department of Biological Sciences, Academy of Medical Sciences, Malawi University of Science and Technology, Thyolo, Malawi
- Correspondence: Peter Ngulube, Email
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14
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Kyei-Baafour E, Kusi KA, Arthur FK, Tiendrebeogo RW, Owusu-Yeboa E, Singh SK, Friedrich S, Gerds TA, Dodoo D, Theisen M, Adu B. High opsonic phagocytosis activity and growth inhibition of merozoites are associated with RON4 antibody levels and protect against febrile malaria in Ghanaian children. Front Immunol 2023; 14:1161301. [PMID: 37197657 PMCID: PMC10183564 DOI: 10.3389/fimmu.2023.1161301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 04/17/2023] [Indexed: 05/19/2023] Open
Abstract
Background Naturally acquired immunity to malaria may involve different immune mechanisms working in concert, however, their respective contributions and potential antigenic targets have not been clearly established. Here, we assessed the roles of opsonic phagocytosis and antibody-mediated merozoite growth inhibition in Plasmodium falciparum (P. falciparum) infection outcomes in Ghanaian children. Methods The levels of merozoite opsonic phagocytosis, growth inhibition activities and six P. falciparum antigen-specific IgG of plasma samples from children (n=238, aged 0.5 to 13 years) were measured at baseline prior to the malaria seasons in southern Ghana. The children were then actively and passively followed up for febrile malaria and asymptomatic P. falciparum infection detection in a 50-week longitudinal cohort. P. falciparum infection outcome was modelled as a function of the measured immune parameters while accounting for important demographic factors. Results High plasma activity of opsonic phagocytosis [adjusted odds ratio (aOR)= 0.16; 95%CI= 0.05 - 0.50, p = 0.002], and growth inhibition (aOR=0.15; 95% CI = 0.04-0.47; p = 0.001) were individually associated with protection against febrile malaria. There was no evidence of correlation (b= 0.13; 95% CI= -0.04-0.30; p=0.14) between the two assays. IgG antibodies against MSPDBL1 correlated with opsonic phagocytosis (OP) while IgG against PfRh2a correlated with growth inhibition. Notably, IgG antibodies against RON4 correlated with both assays. Conclusion Opsonic phagocytosis and growth inhibition are protective immune mechanisms against malaria that may be acting independently to confer overall protection. Vaccines incorporating RON4 may benefit from both immune mechanisms.
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Affiliation(s)
- Eric Kyei-Baafour
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon Accra, Ghana
- Department of Biochemistry and Biotechnology, College of Science, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Kwadwo Asamoah Kusi
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon Accra, Ghana
| | - Fareed K.N. Arthur
- Department of Biochemistry and Biotechnology, College of Science, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Regis W. Tiendrebeogo
- Centre for Medical Parasitology at Department of International Health, Immunology and Microbiology, University of Copenhagen and Department of Infectious Diseases, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
- Department for Congenital Disorders, Statens Serum Institut, Copenhagen, Denmark
| | - Eunice Owusu-Yeboa
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon Accra, Ghana
| | - Susheel K. Singh
- Centre for Medical Parasitology at Department of International Health, Immunology and Microbiology, University of Copenhagen and Department of Infectious Diseases, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
- Department for Congenital Disorders, Statens Serum Institut, Copenhagen, Denmark
| | - Sarah Friedrich
- Section of Biostatistics, Department of Public Health, University of Copenhagen, Copenhagen, Denmark
- Department of Medical Statistics, University Medical Center Goettingen, Goettingen, Germany
| | - Thomas A. Gerds
- Section of Biostatistics, Department of Public Health, University of Copenhagen, Copenhagen, Denmark
| | - Daniel Dodoo
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon Accra, Ghana
| | - Michael Theisen
- Centre for Medical Parasitology at Department of International Health, Immunology and Microbiology, University of Copenhagen and Department of Infectious Diseases, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
- Department for Congenital Disorders, Statens Serum Institut, Copenhagen, Denmark
| | - Bright Adu
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon Accra, Ghana
- *Correspondence: Bright Adu,
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15
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Rashidi S, Mansouri R, Ali-Hassanzadeh M, Muro A, Nguewa P, Manzano-Román R. The Defensive Interactions of Prominent Infectious Protozoan Parasites: The Host's Complement System. Biomolecules 2022; 12:1564. [PMID: 36358913 PMCID: PMC9687244 DOI: 10.3390/biom12111564] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 10/16/2022] [Accepted: 10/21/2022] [Indexed: 12/30/2023] Open
Abstract
The complement system exerts crucial functions both in innate immune responses and adaptive humoral immunity. This pivotal system plays a major role dealing with pathogen invasions including protozoan parasites. Different pathogens including parasites have developed sophisticated strategies to defend themselves against complement killing. Some of these strategies include the employment, mimicking or inhibition of host's complement regulatory proteins, leading to complement evasion. Therefore, parasites are proven to use the manipulation of the complement system to assist them during infection and persistence. Herein, we attempt to study the interaction´s mechanisms of some prominent infectious protozoan parasites including Plasmodium, Toxoplasma, Trypanosoma, and Leishmania dealing with the complement system. Moreover, several crucial proteins that are expressed, recruited or hijacked by parasites and are involved in the modulation of the host´s complement system are selected and their role for efficient complement killing or lysis evasion is discussed. In addition, parasite's complement regulatory proteins appear as plausible therapeutic and vaccine targets in protozoan parasitic infections. Accordingly, we also suggest some perspectives and insights useful in guiding future investigations.
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Affiliation(s)
- Sajad Rashidi
- Molecular and Medicine Research Center, Khomein University of Medical Sciences, Khomein 38811, Iran
- Department of Medical Laboratory Sciences, Khomein University of Medical Sciences, Khomein 38811, Iran
| | - Reza Mansouri
- Department of Immunology, Faculty of Medicine, Shahid Sadoughi University of Medical Sciences and Health Services, Yazd 8915173143, Iran
| | - Mohammad Ali-Hassanzadeh
- Department of Immunology, School of Medicine, Jiroft University of Medical Sciences, Jiroft 7861615765, Iran
| | - Antonio Muro
- Infectious and Tropical Diseases Group (e-INTRO), Institute of Biomedical Research of Salamanca-Research Center for Tropical Diseases at the University of Salamanca (IBSAL-CIETUS), Faculty of Pharmacy, University of Salamanca, 37008 Salamanca, Spain
| | - Paul Nguewa
- Department of Microbiology and Parasitology, ISTUN Institute of Tropical Health, IdiSNA (Navarra Institute for Health Research), University of Navarra, C/Irunlarrea 1, 31008 Pamplona, Spain
| | - Raúl Manzano-Román
- Infectious and Tropical Diseases Group (e-INTRO), Institute of Biomedical Research of Salamanca-Research Center for Tropical Diseases at the University of Salamanca (IBSAL-CIETUS), Faculty of Pharmacy, University of Salamanca, 37008 Salamanca, Spain
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16
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Mueller I, Vantaux A, Karl S, Laman M, Witkowski B, Pepey A, Vinit R, White M, Barry A, Beeson JG, Robinson LJ. Asia-Pacific ICEMR: Understanding Malaria Transmission to Accelerate Malaria Elimination in the Asia Pacific Region. Am J Trop Med Hyg 2022; 107:131-137. [PMID: 36228917 PMCID: PMC9662229 DOI: 10.4269/ajtmh.21-1336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2021] [Accepted: 07/06/2022] [Indexed: 01/31/2023] Open
Abstract
Gaining an in-depth understanding of malaria transmission requires integrated, multifaceted research approaches. The Asia-Pacific International Center of Excellence in Malaria Research (ICEMR) is applying specifically developed molecular and immunological assays, in-depth entomological assessments, and advanced statistical and mathematical modeling approaches to a rich series of longitudinal cohort and cross-sectional studies in Papua New Guinea and Cambodia. This is revealing both the essential contribution of forest-based transmission and the particular challenges posed by Plasmodium vivax to malaria elimination in Cambodia. In Papua New Guinea, these studies document the complex host-vector-parasite interactions that are underlying both the stunning reductions in malaria burden from 2006 to 2014 and the significant resurgence in transmission in 2016 to 2018. Here we describe the novel analytical, surveillance, molecular, and immunological tools that are being applied in our ongoing Asia-Pacific ICEMR research program.
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Affiliation(s)
- Ivo Mueller
- Population Health & Immunity Division, Walter + Eliza Hall Institutes, Melbourne, Australia
- University of Melbourne, Melbourne, Australia
| | | | - Stephan Karl
- Australian Institute of Tropical Health & Medicine, James Cook University, Cairns, Australia
- PNG Institute of Medical Research, Madang, Papua New Guinea
| | - Moses Laman
- PNG Institute of Medical Research, Madang, Papua New Guinea
| | | | - Anais Pepey
- Institute Pasteur Cambodia, Phnom Penh, Cambodia
| | - Rebecca Vinit
- PNG Institute of Medical Research, Madang, Papua New Guinea
| | | | - Alyssa Barry
- Deakin University, Geelong, Australia
- Burnet Institute, Melbourne, Australia
| | - James G. Beeson
- University of Melbourne, Melbourne, Australia
- Burnet Institute, Melbourne, Australia
- Monash University, Victoria, Australia
| | - Leanne J. Robinson
- Population Health & Immunity Division, Walter + Eliza Hall Institutes, Melbourne, Australia
- PNG Institute of Medical Research, Madang, Papua New Guinea
- Burnet Institute, Melbourne, Australia
- Monash University, Victoria, Australia
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17
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The impact of human complement on the clinical outcome of malaria infection. Mol Immunol 2022; 151:19-28. [PMID: 36063583 DOI: 10.1016/j.molimm.2022.08.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 08/19/2022] [Accepted: 08/25/2022] [Indexed: 11/21/2022]
Abstract
The tropical disease malaria remains a major cause of global morbidity. Once transmitted to the human by a blood-feeding mosquito, the unicellular malaria parasite comes into contact with the complement system and continues to interact with human complement during its intraerythrocytic replication cycles. In the course of infection, both the classical and the alternative pathway of complement are activated, leading to parasite opsonization and lysis as well as the induction of complement-binding antibodies. While complement activity can be linked to the severity of malaria, it remains to date unclear, whether human complement is beneficial for protective immunity or if extensive complement reactions may rather enhance pathogenesis. In addition, the parasite has evolved molecular strategies to circumvent attack by human complement and has even developed means to utilize complement factors as mediators of host cell infection. In this review, we highlight current knowledge on the role of human complement for the progression of malaria infection. We discuss the various types of interactions between malaria parasites and complement factors with regard to immunity and infection outcome and set a special emphasis on the dual role of complement in the context of parasite fitness.
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18
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Oulton T, Obiero J, Rodriguez I, Ssewanyana I, Dabbs RA, Bachman CM, Greenhouse B, Drakeley C, Felgner PL, Stone W, Tetteh KKA. Plasmodium falciparum serology: A comparison of two protein production methods for analysis of antibody responses by protein microarray. PLoS One 2022; 17:e0273106. [PMID: 36037183 PMCID: PMC9423672 DOI: 10.1371/journal.pone.0273106] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 08/02/2022] [Indexed: 12/02/2022] Open
Abstract
The evaluation of protein antigens as putative serologic biomarkers of infection has increasingly shifted to high-throughput, multiplex approaches such as the protein microarray. In vitro transcription/translation (IVTT) systems-a similarly high-throughput protein expression method-are already widely utilised in the production of protein microarrays, though purified recombinant proteins derived from more traditional whole cell based expression systems also play an important role in biomarker characterisation. Here we have performed a side-by-side comparison of antigen-matched protein targets from an IVTT and purified recombinant system, on the same protein microarray. The magnitude and range of antibody responses to purified recombinants was found to be greater than that of IVTT proteins, and responses between targets from different expression systems did not clearly correlate. However, responses between amino acid sequence-matched targets from each expression system were more closely correlated. Despite the lack of a clear correlation between antigen-matched targets produced in each expression system, our data indicate that protein microarrays produced using either method can be used confidently, in a context dependent manner, though care should be taken when comparing data derived from contrasting approaches.
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Affiliation(s)
- Tate Oulton
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Joshua Obiero
- Department of Physiology and Biophysics, University of California, Irvine, Irvine, CA, United States of America
| | - Isabel Rodriguez
- Department of Medicine, University of California San Francisco, San Francisco, California, United States of America
| | - Isaac Ssewanyana
- Infectious Diseases Research Collaboration, Kampala, Uganda
- Makerere University College of Health Sciences, Kampala, Uganda
| | - Rebecca A. Dabbs
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | - Bryan Greenhouse
- Department of Medicine, University of California San Francisco, San Francisco, California, United States of America
| | - Chris Drakeley
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Phil L. Felgner
- Department of Physiology and Biophysics, University of California, Irvine, Irvine, CA, United States of America
| | - Will Stone
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Kevin K. A. Tetteh
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
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19
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Tursi NJ, Reeder SM, Flores-Garcia Y, Bah MA, Mathis-Torres S, Salgado-Jimenez B, Esquivel R, Xu Z, Chu JD, Humeau L, Patel A, Zavala F, Weiner DB. Engineered DNA-encoded monoclonal antibodies targeting Plasmodium falciparum circumsporozoite protein confer single dose protection in a murine malaria challenge model. Sci Rep 2022; 12:14313. [PMID: 35995959 PMCID: PMC9395511 DOI: 10.1038/s41598-022-18375-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 05/06/2022] [Indexed: 12/15/2022] Open
Abstract
Novel approaches for malaria prophylaxis remain important. Synthetic DNA-encoded monoclonal antibodies (DMAbs) are a promising approach to generate rapid, direct in vivo host-generated mAbs with potential benefits in production simplicity and distribution coupled with genetic engineering. Here, we explore this approach in a malaria challenge model. We engineered germline-reverted DMAbs based on human mAb clones CIS43, 317, and L9 which target a junctional epitope, major repeat, and minor repeat of the Plasmodium falciparum circumsporozoite protein (CSP) respectively. DMAb variants were encoded into a plasmid vector backbone and their expression and binding profiles were characterized. We demonstrate long-term serological expression of DMAb constructs resulting in in vivo efficacy of CIS43 GL and 317 GL in a rigorous mosquito bite mouse challenge model. Additionally, we engineered an Fc modified variant of CIS43 and L9-based DMAbs to ablate binding to C1q to test the impact of complement-dependent Fc function on challenge outcomes. Complement knockout variant DMAbs demonstrated similar protection to that of WT Fc DMAbs supporting the notion that direct binding to the parasite is sufficient for the protection observed. Further investigation of DMAbs for malaria prophylaxis appears of importance.
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Affiliation(s)
- Nicholas J Tursi
- Vaccine and Immunotherapy Center, The Wistar Institute, Philadelphia, PA, 19104, USA
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Sophia M Reeder
- Vaccine and Immunotherapy Center, The Wistar Institute, Philadelphia, PA, 19104, USA
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Yevel Flores-Garcia
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, 21205, USA
| | - Mamadou A Bah
- Vaccine and Immunotherapy Center, The Wistar Institute, Philadelphia, PA, 19104, USA
| | - Shamika Mathis-Torres
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, 21205, USA
| | - Berenice Salgado-Jimenez
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, 21205, USA
| | - Rianne Esquivel
- Vaccine and Immunotherapy Center, The Wistar Institute, Philadelphia, PA, 19104, USA
| | - Ziyang Xu
- Vaccine and Immunotherapy Center, The Wistar Institute, Philadelphia, PA, 19104, USA
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Jacqueline D Chu
- Vaccine and Immunotherapy Center, The Wistar Institute, Philadelphia, PA, 19104, USA
| | - Laurent Humeau
- Inovio Pharmaceuticals, Plymouth Meeting, PA, 19462, USA
| | - Ami Patel
- Vaccine and Immunotherapy Center, The Wistar Institute, Philadelphia, PA, 19104, USA
| | - Fidel Zavala
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, 21205, USA
| | - David B Weiner
- Vaccine and Immunotherapy Center, The Wistar Institute, Philadelphia, PA, 19104, USA.
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20
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Chan JA, Loughland JR, de la Parte L, Okano S, Ssewanyana I, Nalubega M, Nankya F, Musinguzi K, Rek J, Arinaitwe E, Tipping P, Bourke P, Andrew D, Dooley N, SheelaNair A, Wines BD, Hogarth PM, Beeson JG, Greenhouse B, Dorsey G, Kamya M, Hartel G, Minigo G, Feeney M, Jagannathan P, Boyle MJ. Age-dependent changes in circulating Tfh cells influence development of functional malaria antibodies in children. Nat Commun 2022; 13:4159. [PMID: 35851033 PMCID: PMC9293980 DOI: 10.1038/s41467-022-31880-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Accepted: 07/08/2022] [Indexed: 01/29/2023] Open
Abstract
T-follicular helper (Tfh) cells are key drivers of antibodies that protect from malaria. However, little is known regarding the host and parasite factors that influence Tfh and functional antibody development. Here, we use samples from a large cross-sectional study of children residing in an area of high malaria transmission in Uganda to characterize Tfh cells and functional antibodies to multiple parasites stages. We identify a dramatic re-distribution of the Tfh cell compartment with age that is independent of malaria exposure, with Th2-Tfh cells predominating in early childhood, while Th1-Tfh cell gradually increase to adult levels over the first decade of life. Functional antibody acquisition is age-dependent and hierarchical acquired based on parasite stage, with merozoite responses followed by sporozoite and gametocyte antibodies. Antibodies are boosted in children with current infection, and are higher in females. The children with the very highest antibody levels have increased Tfh cell activation and proliferation, consistent with a key role of Tfh cells in antibody development. Together, these data reveal a complex relationship between the circulating Tfh compartment, antibody development and protection from malaria.
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Affiliation(s)
- Jo-Anne Chan
- Burnet Institute, Melbourne, VIC, Australia
- Department of Immunology, Central Clinical School, Monash University, Melbourne, VIC, Australia
- Department of Medicine, The University of Melbourne, Parkville, VIC, Australia
| | - Jessica R Loughland
- QIMR-Berghofer Medical Research Institute, Herston, QLD, Australia
- Global and Tropical Health Division, Menzies School of Health Research, Tiwi, Australia
| | | | - Satomi Okano
- QIMR-Berghofer Medical Research Institute, Herston, QLD, Australia
| | - Isaac Ssewanyana
- Infectious Diseases Research Collaboration, Kampala, Uganda
- London School of Hygiene and Tropical Medicine, London, UK
| | - Mayimuna Nalubega
- QIMR-Berghofer Medical Research Institute, Herston, QLD, Australia
- Infectious Diseases Research Collaboration, Kampala, Uganda
- Faculty of Medicine, University of Queensland, Brisbane, QLD, Australia
| | | | | | - John Rek
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | | | - Peta Tipping
- Global and Tropical Health Division, Menzies School of Health Research, Tiwi, Australia
| | - Peter Bourke
- Division of Medicine, Cairns Hospital, Manunda, QLD, Australia
| | - Dean Andrew
- QIMR-Berghofer Medical Research Institute, Herston, QLD, Australia
| | - Nicholas Dooley
- QIMR-Berghofer Medical Research Institute, Herston, QLD, Australia
- Griffith University, Brisbane, QLD, Australia
| | - Arya SheelaNair
- QIMR-Berghofer Medical Research Institute, Herston, QLD, Australia
| | - Bruce D Wines
- Burnet Institute, Melbourne, VIC, Australia
- Department of Immunology, Central Clinical School, Monash University, Melbourne, VIC, Australia
- Department of Clinical Pathology, The University of Melbourne, Parkville, VIC, Australia
| | - P Mark Hogarth
- Burnet Institute, Melbourne, VIC, Australia
- Department of Immunology, Central Clinical School, Monash University, Melbourne, VIC, Australia
- Department of Clinical Pathology, The University of Melbourne, Parkville, VIC, Australia
| | - James G Beeson
- Burnet Institute, Melbourne, VIC, Australia
- Department of Medicine, The University of Melbourne, Parkville, VIC, Australia
- Department of Microbiology, Central Clinical School, Monash University, Melbourne, VIC, Australia
| | | | - Grant Dorsey
- University of California San Francisco, San Francisco, CA, USA
| | - Moses Kamya
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Gunter Hartel
- QIMR-Berghofer Medical Research Institute, Herston, QLD, Australia
| | - Gabriela Minigo
- Global and Tropical Health Division, Menzies School of Health Research, Tiwi, Australia
- College of Health and Human Sciences, Charles Darwin University, Darwin, NT, Australia
| | - Margaret Feeney
- University of California San Francisco, San Francisco, CA, USA
| | | | - Michelle J Boyle
- Burnet Institute, Melbourne, VIC, Australia.
- QIMR-Berghofer Medical Research Institute, Herston, QLD, Australia.
- Global and Tropical Health Division, Menzies School of Health Research, Tiwi, Australia.
- Faculty of Medicine, University of Queensland, Brisbane, QLD, Australia.
- Griffith University, Brisbane, QLD, Australia.
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21
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Gonzales SJ, Clarke KN, Batugedara G, Garza R, Braddom AE, Reyes RA, Ssewanyana I, Garrison KC, Ippolito GC, Greenhouse B, Bol S, Bunnik EM. A Molecular Analysis of Memory B Cell and Antibody Responses Against Plasmodium falciparum Merozoite Surface Protein 1 in Children and Adults From Uganda. Front Immunol 2022; 13:809264. [PMID: 35720313 PMCID: PMC9201334 DOI: 10.3389/fimmu.2022.809264] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Accepted: 05/05/2022] [Indexed: 01/18/2023] Open
Abstract
Memory B cells (MBCs) and plasma antibodies against Plasmodium falciparum (Pf) merozoite antigens are important components of the protective immune response against malaria. To gain understanding of how responses against Pf develop in these two arms of the humoral immune system, we evaluated MBC and antibody responses against the most abundant merozoite antigen, full-length Pf merozoite surface protein 1 (PfMSP1FL), in individuals from a region in Uganda with high Pf transmission. Our results showed that PfMSP1FL-specific B cells in adults with immunological protection against malaria were predominantly IgG+ classical MBCs, while children with incomplete protection mainly harbored IgM+ PfMSP1FL-specific classical MBCs. In contrast, anti-PfMSP1FL plasma IgM reactivity was minimal in both children and adults. Instead, both groups showed high plasma IgG reactivity against PfMSP1FL, with broadening of the response against non-3D7 strains in adults. The B cell receptors encoded by PfMSP1FL-specific IgG+ MBCs carried high levels of amino acid substitutions and recognized relatively conserved epitopes on the highly variable PfMSP1 protein. Proteomics analysis of PfMSP119-specific IgG in plasma of an adult revealed a limited repertoire of anti-MSP1 antibodies, most of which were IgG1 or IgG3. Similar to B cell receptors of PfMSP1FL-specific MBCs, anti-PfMSP119 IgGs had high levels of amino acid substitutions and their sequences were predominantly found in classical MBCs, not atypical MBCs. Collectively, these results showed evolution of the PfMSP1-specific humoral immune response with cumulative Pf exposure, with a shift from IgM+ to IgG+ B cell memory, diversification of B cells from germline, and stronger recognition of PfMSP1 variants by the plasma IgG repertoire.
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Affiliation(s)
- S. Jake Gonzales
- Department of Microbiology, Immunology and Molecular Genetics, Long School of Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Kathleen N. Clarke
- Department of Microbiology, Immunology and Molecular Genetics, Long School of Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Gayani Batugedara
- Department of Microbiology, Immunology and Molecular Genetics, Long School of Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Rolando Garza
- Department of Microbiology, Immunology and Molecular Genetics, Long School of Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Ashley E. Braddom
- Department of Microbiology, Immunology and Molecular Genetics, Long School of Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Raphael A. Reyes
- Department of Microbiology, Immunology and Molecular Genetics, Long School of Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Isaac Ssewanyana
- Infectious Disease Research Collaboration, Kampala, Uganda
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Kendra C. Garrison
- Department of Chemical Engineering, University of Texas at Austin, Austin, TX, United States
| | - Gregory C. Ippolito
- Department of Molecular Biosciences and Department of Oncology, Dell Medical School, University of Texas at Austin, Austin, TX, United States
| | - Bryan Greenhouse
- Department of Medicine, University of California San Francisco, San Francisco, CA, United States
| | - Sebastiaan Bol
- Department of Microbiology, Immunology and Molecular Genetics, Long School of Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Evelien M. Bunnik
- Department of Microbiology, Immunology and Molecular Genetics, Long School of Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
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22
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Roberts AJ, Ong HB, Clare S, Brandt C, Harcourt K, Franssen SU, Cotton JA, Müller-Sienerth N, Wright GJ. Systematic identification of genes encoding cell surface and secreted proteins that are essential for in vitro growth and infection in Leishmania donovani. PLoS Pathog 2022; 18:e1010364. [PMID: 35202447 PMCID: PMC8903277 DOI: 10.1371/journal.ppat.1010364] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 03/08/2022] [Accepted: 02/11/2022] [Indexed: 11/23/2022] Open
Abstract
Leishmaniasis is an infectious disease caused by protozoan parasites belonging to the genus Leishmania for which there are no approved human vaccines. Infections localise to different tissues in a species-specific manner with the visceral form of the disease caused by Leishmania donovani and L. infantum being the most deadly in humans. Although Leishmania spp. parasites are predominantly intracellular, the visceral disease can be prevented in dogs by vaccinating with a complex mixture of secreted products from cultures of L. infantum promastigotes. With the logic that extracellular parasite proteins make good subunit vaccine candidates because they are directly accessible to vaccine-elicited host antibodies, here we attempt to discover proteins that are essential for in vitro growth and host infection with the goal of identifying subunit vaccine candidates. Using an in silico analysis of the Leishmania donovani genome, we identified 92 genes encoding proteins that are predicted to be secreted or externally anchored to the parasite membrane by a single transmembrane region or a GPI anchor. By selecting a transgenic L. donovani parasite that expresses both luciferase and the Cas9 nuclease, we systematically attempted to target all 92 genes by CRISPR genome editing and identified four that were required for in vitro growth. For fifty-five genes, we infected cohorts of mice with each mutant parasite and by longitudinally quantifying parasitaemia with bioluminescent imaging, showed that nine genes had evidence of an attenuated infection although all ultimately established an infection. Finally, we expressed two genes as full-length soluble recombinant proteins and tested them as subunit vaccine candidates in a murine preclinical infection model. Both proteins elicited significant levels of protection against the uncontrolled development of a splenic infection warranting further investigation as subunit vaccine candidates against this deadly infectious tropical disease. Leishmaniasis is a parasitic infectious disease that is responsible for many tens of thousands of human deaths per year, primarily in impoverished parts of the world. Although there are drugs to treat this parasite infection, resistance is emerging and there are no approved human vaccines. Extracellular parasite proteins can make good vaccine targets because they are directly accessible to host antibodies; however, not all parasite surface proteins can elicit protective immune responses. With the goal of identifying new vaccine targets, we selected over 90 genes that encode parasite cell surface and secreted proteins and used the latest CRISPR gene editing technology to individually target them. Using these mutant parasites, we identified four genes required for parasite growth in the laboratory. We expressed two of the proteins as subunit vaccines and a preclinical infection model was used to determine if they could elicit protective immune responses. We found that two of our candidates were able to confer significant levels of protection in a murine model of visceral leishmaniasis. Our study will contribute to the search for a highly effective vaccine against visceral leishmaniasis to improve the lives of people living in some of the poorest regions on the planet.
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Affiliation(s)
- Adam J. Roberts
- Cell Surface Signalling Laboratory, Wellcome Sanger Institute, Hinxton, Cambridge, United Kingdom
| | - Han B. Ong
- Cell Surface Signalling Laboratory, Wellcome Sanger Institute, Hinxton, Cambridge, United Kingdom
| | - Simon Clare
- Pathogen Support Team, Wellcome Sanger Institute, Hinxton, Cambridge, United Kingdom
| | - Cordelia Brandt
- Pathogen Support Team, Wellcome Sanger Institute, Hinxton, Cambridge, United Kingdom
| | - Katherine Harcourt
- Pathogen Support Team, Wellcome Sanger Institute, Hinxton, Cambridge, United Kingdom
| | - Susanne U. Franssen
- Parasite Genomics, Wellcome Sanger Institute, Hinxton, Cambridge, United Kingdom
| | - James A. Cotton
- Parasite Genomics, Wellcome Sanger Institute, Hinxton, Cambridge, United Kingdom
| | - Nicole Müller-Sienerth
- Cell Surface Signalling Laboratory, Wellcome Sanger Institute, Hinxton, Cambridge, United Kingdom
| | - Gavin J. Wright
- Cell Surface Signalling Laboratory, Wellcome Sanger Institute, Hinxton, Cambridge, United Kingdom
- Department of Biology, Hull York Medical School, York Biomedical Research Institute, University of York, York, United Kingdom
- * E-mail:
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23
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Knudsen AS, Walker MR, Agullet JP, Björnsson KH, Bassi MR, Barfod L. Enhancing neutralization of Plasmodium falciparum using a novel monoclonal antibody against the rhoptry-associated membrane antigen. Sci Rep 2022; 12:3040. [PMID: 35197516 PMCID: PMC8866459 DOI: 10.1038/s41598-022-06921-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 01/31/2022] [Indexed: 11/09/2022] Open
Abstract
The pathogenesis of malaria is associated with blood-stage infection and there is strong evidence that antibodies specific to parasite blood-stage antigens can control parasitemia. This provides a strong rational for applying blood-stage antigen components in a multivalent vaccine, as the induced antibodies in combination can enhance protection. The Plasmodium falciparum rhoptry-associated membrane antigen (PfRAMA) is a promising vaccine target, due to its fundamental role in merozoite invasion and low level of polymorphism. Polyclonal antibodies against PfRAMA are able to inhibit P. falciparum growth and interact synergistically when combined with antibodies against P. falciparum reticulocyte-binding protein 5 (PfRh5) or cysteine-rich protective antigen (PfCyRPA). In this study, we identified a novel PfRAMA-specific mAb with neutralizing activity, which in combination with PfRh5- or PfCyRPA-specific mAbs potentiated the neutralizing effect. By applying phage display technology, we mapped the protective epitope to be in the C-terminal region of PfRAMA. Our results confirmed previous finding of synergy between PfRAMA-, PfRh5- and PfCyRPA-specific antibodies, thereby paving the way of testing these antigens (or fragments of these antigens) in combination to improve the efficacy of blood-stage malaria vaccines. The results emphasize the importance of directing antibody responses towards protective epitopes, as the majority of anti-PfRAMA mAbs were unable to inhibit merozoite invasion of erythrocytes.
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Affiliation(s)
- Anne S Knudsen
- Department of Immunology and Microbiology, Centre for Medical Parasitology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Melanie R Walker
- Department of Immunology and Microbiology, Centre for Medical Parasitology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Judit P Agullet
- Department of Immunology and Microbiology, Centre for Medical Parasitology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Kasper H Björnsson
- Department of Immunology and Microbiology, Centre for Medical Parasitology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Maria R Bassi
- Department of Immunology and Microbiology, Centre for Medical Parasitology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Lea Barfod
- Department of Immunology and Microbiology, Centre for Medical Parasitology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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24
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Addy JW, Bediako Y, Ndungu FM, Valetta JJ, Reid AJ, Mwacharo J, Ngoi JM, Wambua J, Otieno E, Musyoki J, Said K, Berriman M, Marsh K, Bejon P, Recker M, Langhorne J. 10-year longitudinal study of malaria in children: Insights into acquisition and maintenance of naturally acquired immunity. Wellcome Open Res 2022; 6:79. [PMID: 35141425 PMCID: PMC8822141 DOI: 10.12688/wellcomeopenres.16562.3] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/31/2022] [Indexed: 01/26/2023] Open
Abstract
Background: Studies of long-term malaria cohorts have provided essential insights into how Plasmodium falciparum interacts with humans, and influences the development of antimalarial immunity. Immunity to malaria is acquired gradually after multiple infections, some of which present with clinical symptoms. However, there is considerable variation in the number of clinical episodes experienced by children of the same age within the same cohort. Understanding this variation in clinical symptoms and how it relates to the development of naturally acquired immunity is crucial in identifying how and when some children stop experiencing further malaria episodes. Where variability in clinical episodes may result from different rates of acquisition of immunity, or from variable exposure to the parasite. Methods: Using data from a longitudinal cohort of children residing in an area of moderate P. falciparum transmission in Kilifi district, Kenya, we fitted cumulative episode curves as monotonic-increasing splines, to 56 children under surveillance for malaria from the age of 5 to 15. Results: There was large variability in the accumulation of numbers of clinical malaria episodes experienced by the children, despite being of similar age and living in the same general location. One group of children from a particular sub-region of the cohort stopped accumulating clinical malaria episodes earlier than other children in the study. Despite lack of further clinical episodes of malaria, these children had higher asymptomatic parasite densities and higher antibody titres to a panel of P. falciparum blood-stage antigens. Conclusions: This suggests development of clinical immunity rather than lack of exposure to the parasite, and supports the view that this immunity to malaria disease is maintained by a greater exposure to P. falciparum, and thus higher parasite burdens. Our study illustrates the complexity of anti-malaria immunity and underscores the need for analyses which can sufficiently reflect the heterogeneity within endemic populations.
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Affiliation(s)
- John W.G. Addy
- Malaria Immunology Laboratory, Francis Crick Institute, London, UK
| | - Yaw Bediako
- Malaria Immunology Laboratory, Francis Crick Institute, London, UK
- West African Centre for Cell Biology of Infectious Pathogens, University of Ghana, Accra, Ghana
| | | | - John Joseph Valetta
- School of Mathematics and Statistics, University of St Andrews, St Andrews, UK
| | - Adam J. Reid
- Parasite Genomics, Wellcome Sanger Institute, Hixton, UK
| | | | | | - Joshua Wambua
- KEMRI/Wellcome Trust Research Programme, Kilifi, Kenya
| | - Edward Otieno
- KEMRI/Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Khadija Said
- KEMRI/Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Kevin Marsh
- Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
| | - Philip Bejon
- KEMRI/Wellcome Trust Research Programme, Kilifi, Kenya
| | - Mario Recker
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Penryn, UK
| | - Jean Langhorne
- Malaria Immunology Laboratory, Francis Crick Institute, London, UK
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25
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Naung MT, Martin E, Munro J, Mehra S, Guy AJ, Laman M, Harrison GLA, Tavul L, Hetzel M, Kwiatkowski D, Mueller I, Bahlo M, Barry AE. Global diversity and balancing selection of 23 leading Plasmodium falciparum candidate vaccine antigens. PLoS Comput Biol 2022; 18:e1009801. [PMID: 35108259 PMCID: PMC8843232 DOI: 10.1371/journal.pcbi.1009801] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Revised: 02/14/2022] [Accepted: 01/03/2022] [Indexed: 12/30/2022] Open
Abstract
Investigation of the diversity of malaria parasite antigens can help prioritize and validate them as vaccine candidates and identify the most common variants for inclusion in vaccine formulations. Studies of vaccine candidates of the most virulent human malaria parasite, Plasmodium falciparum, have focused on a handful of well-known antigens, while several others have never been studied. Here we examine the global diversity and population structure of leading vaccine candidate antigens of P. falciparum using the MalariaGEN Pf3K (version 5.1) resource, comprising more than 2600 genomes from 15 malaria endemic countries. A stringent variant calling pipeline was used to extract high quality antigen gene 'haplotypes' from the global dataset and a new R-package named VaxPack was used to streamline population genetic analyses. In addition, a newly developed algorithm that enables spatial averaging of selection pressure on 3D protein structures was applied to the dataset. We analysed the genes encoding 23 leading and novel candidate malaria vaccine antigens including csp, trap, eba175, ama1, rh5, and CelTOS. Our analysis shows that current malaria vaccine formulations are based on rare haplotypes and thus may have limited efficacy against natural parasite populations. High levels of diversity with evidence of balancing selection was detected for most of the erythrocytic and pre-erythrocytic antigens. Measures of natural selection were then mapped to 3D protein structures to predict targets of functional antibodies. For some antigens, geographical variation in the intensity and distribution of these signals on the 3D structure suggests adaptation to different human host or mosquito vector populations. This study provides an essential framework for the diversity of P. falciparum antigens to be considered in the design of the next generation of malaria vaccines.
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Affiliation(s)
- Myo T. Naung
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Carlton, Victoria, Australia
- Institute of Mental and Physical Health and Clinical Translation (IMPACT), School of Medicine, Deakin University, Geelong, Victoria, Australia
| | - Elijah Martin
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Life Sciences Discipline, Burnet Institute, Melbourne, Victoria, Australia
| | - Jacob Munro
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
| | - Somya Mehra
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Life Sciences Discipline, Burnet Institute, Melbourne, Victoria, Australia
| | - Andrew J. Guy
- School of Science, RMIT University, Melbourne, Victoria, Australia
| | - Moses Laman
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - G. L. Abby Harrison
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Carlton, Victoria, Australia
| | - Livingstone Tavul
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Manuel Hetzel
- Swiss Tropical Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Dominic Kwiatkowski
- Sanger Institute, Hinxton, United Kingdom
- Big Data Institute, University of Oxford, Oxford, United Kingdom
| | - Ivo Mueller
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Carlton, Victoria, Australia
- Division of Parasites and Insect Vectors, Pasteur Institute, Paris, France
| | - Melanie Bahlo
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Carlton, Victoria, Australia
| | - Alyssa E. Barry
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Carlton, Victoria, Australia
- Institute of Mental and Physical Health and Clinical Translation (IMPACT), School of Medicine, Deakin University, Geelong, Victoria, Australia
- Life Sciences Discipline, Burnet Institute, Melbourne, Victoria, Australia
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26
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O'Flaherty K, Roe M, Fowkes FJ. The role of naturally acquired antimalarial antibodies in subclinical
Plasmodium
spp. infection. J Leukoc Biol 2022; 111:1097-1105. [PMID: 35060185 PMCID: PMC9303632 DOI: 10.1002/jlb.5mr1021-537r] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 12/09/2021] [Indexed: 12/17/2022] Open
Affiliation(s)
- Katherine O'Flaherty
- Disease Elimination Program Burnet Institute for Medical Research and Public Health Melbourne Australia
| | - Merryn Roe
- Disease Elimination Program Burnet Institute for Medical Research and Public Health Melbourne Australia
- School of Public Health and Preventive Medicine Monash University Melbourne Australia
| | - Freya J.I. Fowkes
- Disease Elimination Program Burnet Institute for Medical Research and Public Health Melbourne Australia
- School of Public Health and Preventive Medicine Monash University Melbourne Australia
- Centre for Epidemiology and Biostatistics Melbourne School of Population and Global Health, The University of Melbourne Melbourne Australia
- Department of Infectious Disease Monash University Melbourne Australia
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27
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Irani V, Soliman C, Raftis MA, Guy AJ, Elbourne A, Ramsland PA. Expression of monoclonal antibodies for functional and structural studies. METHODS IN MICROBIOLOGY 2022. [DOI: 10.1016/bs.mim.2022.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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28
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Oyong DA, Loughland JR, Soon MSF, Chan JA, Andrew D, Wines BD, Hogarth PM, Olver SD, Collinge AD, Varelias A, Beeson JG, Kenangalem E, Price RN, Anstey NM, Minigo G, Boyle MJ. Adults with Plasmodium falciparum malaria have higher magnitude and quality of circulating T-follicular helper cells compared to children. EBioMedicine 2022; 75:103784. [PMID: 34968760 PMCID: PMC8718734 DOI: 10.1016/j.ebiom.2021.103784] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Revised: 11/28/2021] [Accepted: 12/11/2021] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Protective malarial antibodies are acquired more rapidly in adults than children, independently of cumulative exposure, however the cellular responses mediating these differences are unknown. CD4 T-follicular helper (Tfh) cells have key roles in inducing antibodies, with Th2-Tfh cell activation associated with antibody development in malaria. Whether Tfh cell activation in malaria is age dependent is unknown and no studies have compared Tfh cell activation in children and adults with malaria. METHODS We undertook a comprehensive study of Tfh cells, along with B cells and antibody induction in children and adults with malaria. Activation and proliferation of circulating Tfh (cTfh) cell subsets was measured ex vivo and parasite-specific Tfh cell frequencies and functions studied with Activation Induced Marker (AIM) assays and intracellular cytokine staining. FINDINGS During acute malaria, the magnitude of cTfh cell activation was higher in adults than in children and occurred across all cTfh cell subsets in adults but was restricted only to the Th1-cTfh subset in children. Further, adults had higher levels of parasite-specific cTfh cells, and cTfh cells which produced more Th2-Tfh associated cytokine IL-4. Consistent with a role of higher Tfh cell activation in rapid immune development in adults, adults had higher activation of B cells during infection and higher induction of antibodies 7 and 28 days after malaria compared to children. INTERPRETATION Our data provide evidence that age impacts Tfh cell activation during malaria, and that these differences may influence antibody induction after treatment. Findings have important implications for vaccine development in children. FUNDING This word was supported by the National Health and Medical Research Council of Australia, Wellcome Trust, Charles Darwin University Menzies School of Health Research, Channel 7 Children's Research Foundation, and National Health Institute.
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Affiliation(s)
- Damian A Oyong
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, Northern Territory, Australia; Charles Darwin University, Darwin, NT, Australia
| | - Jessica R Loughland
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, Northern Territory, Australia; QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - Megan S F Soon
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - Jo-Anne Chan
- Burnet Institute, Melbourne, VIC, Australia; Department of Immunology, Central Clinical School, Monash University, VIC, Australia; Department of Medicine, University of Melbourne, VIC, Australia
| | - Dean Andrew
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - Bruce D Wines
- Burnet Institute, Melbourne, VIC, Australia; Department of Immunology, Central Clinical School, Monash University, VIC, Australia; Department of Clinical Pathology, University of Melbourne, VIC, Australia
| | - P Mark Hogarth
- Burnet Institute, Melbourne, VIC, Australia; Department of Immunology, Central Clinical School, Monash University, VIC, Australia; Department of Clinical Pathology, University of Melbourne, VIC, Australia
| | - Stuart D Olver
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - Alika D Collinge
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - Antiopi Varelias
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia; Faculty of Medicine, The University of Queensland, QLD, Australia
| | - James G Beeson
- Burnet Institute, Melbourne, VIC, Australia; Department of Medicine, University of Melbourne, VIC, Australia; Department of Microbiology, Monash University, VIC, Australia
| | - Enny Kenangalem
- Timika Malaria Research Program, Papuan Health and Community Development Foundation, Timika, Papua, Indonesia; District Health Authority, Timika, Papua, Indonesia
| | - Ric N Price
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, Northern Territory, Australia; Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK; Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Nicholas M Anstey
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, Northern Territory, Australia
| | - Gabriela Minigo
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, Northern Territory, Australia; Charles Darwin University, Darwin, NT, Australia
| | - Michelle J Boyle
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, Northern Territory, Australia; QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia; Burnet Institute, Melbourne, VIC, Australia; Faculty of Medicine, The University of Queensland, QLD, Australia.
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29
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Addy JW, Bediako Y, Ndungu FM, Valetta JJ, Reid AJ, Mwacharo J, Ngoi JM, Wambua J, Otieno E, Musyoki J, Said K, Berriman M, Marsh K, Bejon P, Recker M, Langhorne J. 10-year longitudinal study of malaria in children: Insights into acquisition and maintenance of naturally acquired immunity. Wellcome Open Res 2021; 6:79. [PMID: 35141425 PMCID: PMC8822141 DOI: 10.12688/wellcomeopenres.16562.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/22/2021] [Indexed: 01/26/2023] Open
Abstract
Background: Studies of long-term malaria cohorts have provided essential insights into how Plasmodium falciparum interacts with humans, and influences the development of antimalarial immunity. Immunity to malaria is acquired gradually after multiple infections, some of which present with clinical symptoms. However, there is considerable variation in the number of clinical episodes experienced by children of the same age within the same cohort. Understanding this variation in clinical symptoms and how it relates to the development of naturally acquired immunity is crucial in identifying how and when some children stop experiencing further malaria episodes. Where variability in clinical episodes may result from different rates of acquisition of immunity, or from variable exposure to the parasite. Methods: Using data from a longitudinal cohort of children residing in an area of moderate P. falciparum transmission in Kilifi district, Kenya, we fitted cumulative episode curves as monotonic-increasing splines, to 56 children under surveillance for malaria from the age of 5 to 15. Results: There was large variability in the accumulation of numbers of clinical malaria episodes experienced by the children, despite being of similar age and living in the same general location. One group of children from a particular sub-region of the cohort stopped accumulating clinical malaria episodes earlier than other children in the study. Despite lack of further clinical episodes of malaria, these children had higher asymptomatic parasite densities and higher antibody titres to a panel of P. falciparum blood-stage antigens. Conclusions: This suggests development of clinical immunity rather than lack of exposure to the parasite, and supports the view that this immunity to malaria disease is maintained by a greater exposure to P. falciparum, and thus higher parasite burdens. Our study illustrates the complexity of anti-malaria immunity and underscores the need for analyses which can sufficiently reflect the heterogeneity within endemic populations.
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Affiliation(s)
- John W.G. Addy
- Malaria Immunology Laboratory, Francis Crick Institute, London, UK
| | - Yaw Bediako
- Malaria Immunology Laboratory, Francis Crick Institute, London, UK
- West African Centre for Cell Biology of Infectious Pathogens, University of Ghana, Accra, Ghana
| | | | - John Joseph Valetta
- School of Mathematics and Statistics, University of St Andrews, St Andrews, UK
| | - Adam J. Reid
- Parasite Genomics, Wellcome Sanger Institute, Hixton, UK
| | | | | | - Joshua Wambua
- KEMRI/Wellcome Trust Research Programme, Kilifi, Kenya
| | - Edward Otieno
- KEMRI/Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Khadija Said
- KEMRI/Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Kevin Marsh
- Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
| | - Philip Bejon
- KEMRI/Wellcome Trust Research Programme, Kilifi, Kenya
| | - Mario Recker
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Penryn, UK
| | - Jean Langhorne
- Malaria Immunology Laboratory, Francis Crick Institute, London, UK
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30
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Kurtovic L, Drew DR, Dent AE, Kazura JW, Beeson JG. Antibody Targets and Properties for Complement-Fixation Against the Circumsporozoite Protein in Malaria Immunity. Front Immunol 2021; 12:775659. [PMID: 34925347 PMCID: PMC8671933 DOI: 10.3389/fimmu.2021.775659] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 11/15/2021] [Indexed: 01/02/2023] Open
Abstract
The Plasmodium falciparum circumsporozoite protein (CSP) forms the basis of leading subunit malaria vaccine candidates. However, the mechanisms and specific targets of immunity are poorly defined. Recent findings suggest that antibody-mediated complement-fixation and activation play an important role in immunity. Here, we investigated the regions of CSP targeted by functional complement-fixing antibodies and the antibody properties associated with this activity. We quantified IgG, IgM, and functional complement-fixing antibody responses to different regions of CSP among Kenyan adults naturally exposed to malaria (n=102) and using a series of rabbit vaccination studies. Individuals who acquired functional complement-fixing antibodies had higher IgG, IgM and IgG1 and IgG3 to CSP. Acquired complement-fixing antibodies targeted the N-terminal, central-repeat, and C-terminal regions of CSP, and positive responders had greater antibody breadth compared to those who were negative for complement-fixing antibodies (p<0.05). Using rabbit vaccinations as a model, we confirmed that IgG specific to the central-repeat and non-repeat regions of CSP could effectively fix complement. However, vaccination with near full length CSP in rabbits poorly induced antibodies to the N-terminal region compared to naturally-acquired immunity in humans. Poor induction of N-terminal antibodies was also observed in a vaccination study performed in mice. IgG and IgM to all three regions of CSP play a role in mediating complement-fixation, which has important implications for malaria vaccine development.
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Affiliation(s)
- Liriye Kurtovic
- Life Sciences, Burnet Institute, Melbourne, VIC, Australia
- Department of Immunology and Pathology, Monash University, Melbourne, VIC, Australia
| | - Damien R. Drew
- Life Sciences, Burnet Institute, Melbourne, VIC, Australia
| | - Arlene E. Dent
- Center for Global Health and Diseases, Case Western University, Cleveland, OH, United States
| | - James W. Kazura
- Center for Global Health and Diseases, Case Western University, Cleveland, OH, United States
| | - James G. Beeson
- Life Sciences, Burnet Institute, Melbourne, VIC, Australia
- Department of Immunology and Pathology, Monash University, Melbourne, VIC, Australia
- Department of Microbiology, Monash University, Clayton, VIC, Australia
- Department of Medicine, The University of Melbourne, Parkville, VIC, Australia
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31
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Raballah E, Anyona SB, Cheng Q, Munde EO, Hurwitz IF, Onyango C, Ndege C, Hengartner NW, Pacheco MA, Escalante AA, Lambert CG, Ouma C, Obama HCJT, Scheider KA, Seidenberg PD, McMahon BH, Perkins DJ. Complement component 3 mutations alter the longitudinal risk of pediatric malaria and severe malarial anemia. Exp Biol Med (Maywood) 2021; 247:672-682. [PMID: 34842470 DOI: 10.1177/15353702211056272] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Severe malarial anemia (SMA) is a leading cause of childhood morbidity and mortality in holoendemic Plasmodium falciparum transmission regions. To gain enhanced understanding of predisposing factors for SMA, we explored the relationship between complement component 3 (C3) missense mutations [rs2230199 (2307C>G, Arg>Gly102) and rs11569534 (34420G>A, Gly>Asp1224)], malaria, and SMA in a cohort of children (n = 1617 children) over 36 months of follow-up. Variants were selected based on their ability to impart amino acid substitutions that can alter the structure and function of C3. The 2307C>G mutation results in a basic to a polar residue change (Arg to Gly) at position 102 (β-chain) in the macroglobulin-1 (MG1) domain, while 34420G>A elicits a polar to acidic residue change (Gly to Asp) at position 1224 (α-chain) in the thioester-containing domain. After adjusting for multiple comparisons, longitudinal analyses revealed that inheritance of the homozygous mutant (GG) at 2307 enhanced the risk of SMA (RR = 2.142, 95%CI: 1.229-3.735, P = 0.007). The haplotype containing both wild-type alleles (CG) decreased the incident risk ratio of both malaria (RR = 0.897, 95%CI: 0.828-0.972, P = 0.008) and SMA (RR = 0.617, 95%CI: 0.448-0.848, P = 0.003). Malaria incident risk ratio was also reduced in carriers of the GG (Gly102Gly1224) haplotype (RR = 0.941, 95%CI: 0.888-0.997, P = 0.040). Collectively, inheritance of the missense mutations in MG1 and thioester-containing domain influence the longitudinal risk of malaria and SMA in children exposed to intense Plasmodium falciparum transmission.
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Affiliation(s)
- Evans Raballah
- 1104University of New Mexico-Kenya Global Health Programs, Kisumu and Siaya 40100, Kenya.,Department of Medical Laboratory Sciences, 118970School of Public Health Biomedical Sciences and Technology, Masinde Muliro University of Science and Technology, 50100 Kakamega, Kenya
| | - Samuel B Anyona
- 1104University of New Mexico-Kenya Global Health Programs, Kisumu and Siaya 40100, Kenya.,Department of Medical Biochemistry, 118971School of Medicine, Maseno University, 40105 Maseno, Kenya
| | - Qiuying Cheng
- Center for Global Health, Department of Internal Medicine, 1104University of New Mexico, Albuquerque, 87131 NM, USA
| | - Elly O Munde
- 1104University of New Mexico-Kenya Global Health Programs, Kisumu and Siaya 40100, Kenya.,Department of Clinical Medicine, Kirinyaga University School of Health Sciences, Kerugoya 10300, Kenya
| | - Ivy-Foo Hurwitz
- Center for Global Health, Department of Internal Medicine, 1104University of New Mexico, Albuquerque, 87131 NM, USA
| | - Clinton Onyango
- 1104University of New Mexico-Kenya Global Health Programs, Kisumu and Siaya 40100, Kenya
| | - Caroline Ndege
- 1104University of New Mexico-Kenya Global Health Programs, Kisumu and Siaya 40100, Kenya
| | - Nicolas W Hengartner
- Theoretical Division, Theoretical Biology and Biophysics Group, Los Alamos National Laboratory, Los Alamos, 87544 NM, USA
| | - Maria Andreína Pacheco
- Biology Department/Institute of Genomics and Evolutionary Medicine (iGEM), Temple University, Philadelphia, PA 19122, USA
| | - Ananias A Escalante
- Biology Department/Institute of Genomics and Evolutionary Medicine (iGEM), Temple University, Philadelphia, PA 19122, USA
| | - Christophe G Lambert
- Center for Global Health, Department of Internal Medicine, 1104University of New Mexico, Albuquerque, 87131 NM, USA
| | - Collins Ouma
- 1104University of New Mexico-Kenya Global Health Programs, Kisumu and Siaya 40100, Kenya.,Department of Biomedical Sciences and Technology, 118971School of Public Health and Community Development, Maseno University, 40105 Maseno, Kenya
| | - Henri C Jr T Obama
- Department of Applied Computer and Biosciences, University of Applied Sciences Mittweida, Technikumplatz, Mittweida 09648, Germany
| | - Kristan A Scheider
- Department of Applied Computer and Biosciences, University of Applied Sciences Mittweida, Technikumplatz, Mittweida 09648, Germany
| | - Philip D Seidenberg
- Department of Emergency Medicine, 1104University of New Mexico, Albuquerque, NM 87131, USA
| | - Benjamin H McMahon
- Theoretical Division, Theoretical Biology and Biophysics Group, Los Alamos National Laboratory, Los Alamos, 87544 NM, USA
| | - Douglas J Perkins
- 1104University of New Mexico-Kenya Global Health Programs, Kisumu and Siaya 40100, Kenya.,Center for Global Health, Department of Internal Medicine, 1104University of New Mexico, Albuquerque, 87131 NM, USA
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32
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Doolan DL. Malaria research in Australia: looking through the lens of the past towards the future. Int J Parasitol 2021; 51:1255-1263. [PMID: 34780720 DOI: 10.1016/j.ijpara.2021.11.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/05/2021] [Accepted: 11/05/2021] [Indexed: 10/19/2022]
Abstract
Malaria remains a global health priority, with substantial resources devoted to control and intervention since the causative parasite was first identified in 1880. Major advances have been made in discovery and translational research activities aimed at prevention, treatment and control. Laboratory-based, clinical, and field-based studies have complemented public health approaches. Australian scientists have played important roles, developing and applying innovative approaches, novel research tools and cutting-edge technologies in animal and human models of disease, as well as in disease-endemic settings. This article will provide an insight into 50 years of Australian efforts to discover mechanisms and targets of immunity and pathogenesis; develop new diagnostics, drugs, vaccines, and therapeutics; and assess new public health interventions and control measures in malaria-endemic settings.
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Affiliation(s)
- Denise L Doolan
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health & Medicine, James Cook University, Cairns QLD 4878, Australia.
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33
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Nascimento EJM, Norwood B, Parker A, Braun R, Kpamegan E, Dean HJ. Development and Characterization of a Multiplex Assay to Quantify Complement-Fixing Antibodies against Dengue Virus. Int J Mol Sci 2021; 22:ijms222112004. [PMID: 34769432 PMCID: PMC8584793 DOI: 10.3390/ijms222112004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 10/28/2021] [Accepted: 11/02/2021] [Indexed: 12/30/2022] Open
Abstract
Antibodies capable of activating the complement system (CS) when bound with antigen are referred to as "complement-fixing antibodies" and are involved in protection against Flaviviruses. A complement-fixing antibody test has been used in the past to measure the ability of dengue virus (DENV)-specific serum antibodies to activate the CS. As originally developed, the test is time-consuming, cumbersome, and has limited sensitivity for DENV diagnosis. Here, we developed and characterized a novel multiplex anti-DENV complement-fixing assay based on the Luminex platform to quantitate serum antibodies against all four serotypes (DENV1-4) that activate the CS based on their ability to fix the complement component 1q (C1q). The assay demonstrated good reproducibility and showed equivalent performance to a DENV microneutralization assay that has been used to determine DENV serostatus. In non-human primates, antibodies produced in response to primary DENV1-4 infection induced C1q fixation on homologous and heterologous serotypes. Inter-serotype cross-reactivity was associated with homology of the envelope protein. Interestingly, the antibodies produced following vaccination against Zika virus fixed C1q on DENV. The anti-DENV complement fixing antibody assay represents an alternative approach to determine the quality of functional antibodies produced following DENV natural infection or vaccination and a biomarker for dengue serostatus, while providing insights about immunological cross-reactivity among different Flaviviruses.
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34
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Tayipto Y, Liu Z, Mueller I, Longley RJ. Serology for Plasmodium vivax surveillance: A novel approach to accelerate towards elimination. Parasitol Int 2021; 87:102492. [PMID: 34728377 DOI: 10.1016/j.parint.2021.102492] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 08/30/2021] [Accepted: 10/28/2021] [Indexed: 01/13/2023]
Abstract
Plasmodium vivax is the most widespread causative agent of human malaria in the world. Despite the ongoing implementation of malaria control programs, the rate of case reduction has declined over the last 5 years. Hence, surveillance of malaria transmission should be in place to identify and monitor areas that require intensified malaria control interventions. Serological tools may offer additional insights into transmission intensity over parasite and entomological measures, especially as transmission levels decline. Antibodies can be detected in the host system for months to even years after parasite infections have been cleared from the blood, enabling malaria exposure history to be captured. Because the Plasmodium parasite expresses more than 5000 proteins, it is important to a) understand antibody longevity following infection and b) measure antibodies to more than one antigen in order to accurately inform on the exposure and/or immune status of populations. This review summarises current practices for surveillance of P. vivax malaria, the current state of research into serological exposure markers and their potential role for accelerating malaria elimination, and discusses further studies that need to be undertaken to see such technology implemented in malaria-endemic areas.
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Affiliation(s)
- Yanie Tayipto
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia; Department of Medical Biology, University of Melbourne, Melbourne, Victoria, Australia
| | - Zoe Liu
- The Institute for Mental and Physical Health and Clinical Translation, Barwon Health, Deakin University, Geelong, Victoria, Australia; School of Medicine, Centre for Molecular and Medical Research, Deakin University, Geelong, Australia
| | - Ivo Mueller
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia; Department of Medical Biology, University of Melbourne, Melbourne, Victoria, Australia
| | - Rhea J Longley
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia; Department of Medical Biology, University of Melbourne, Melbourne, Victoria, Australia.
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35
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Influence of Host-Related Factors and Exposure to Mosquito Bites on the Dynamics of Antibody Response to Plasmodium falciparum Antigens. Trop Med Infect Dis 2021; 6:tropicalmed6040185. [PMID: 34698307 PMCID: PMC8544703 DOI: 10.3390/tropicalmed6040185] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 09/30/2021] [Accepted: 10/11/2021] [Indexed: 11/24/2022] Open
Abstract
Humoral immunity to Plasmodium falciparum is acquired after repeated infections, and can lead to clinical protection. This study aimed to evaluate how human-, parasite-, and environment-related determinants can modulate the dynamics of IgG responses to Plasmodium falciparum after an infection. Individuals (n = 68, average age = 8.2 years) with uncomplicated malaria were treated with ACT and followed up for 42 days. IgG responses to P. falciparum merozoite antigens (PfMSP1, PfMSP3, PfAMA1, PfGLURP-R0), to whole schizont extract (PfSchz), and to Anopheles gSG6-P1 and Aedes Nterm–34 kDa salivary peptides were measured. Regression analyses were used to identify factors that influence the dynamics of IgG response to P. falciparum antigen between D0 and D42, including demographic and biological factors and the level of exposure to mosquito bites. The dynamics of IgG response to P. falciparum differed according to the antigen. According to multivariate analysis, IgG responses to PfSchz and to PfGLURP-R0 appear to be affected by exposure to Aedes saliva and are associated with age, parasite density, and anti-Plasmodium pre-existing immune response at study inclusion. The present work shows that human exposure to Aedes saliva may contribute, in addition to other factors, to the regulation of anti-Plasmodium immune responses during a natural infection.
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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: 14] [Impact Index Per Article: 4.7] [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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37
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Kurtovic L, Reiling L, Opi DH, Beeson JG. Recent clinical trials inform the future for malaria vaccines. COMMUNICATIONS MEDICINE 2021; 1:26. [PMID: 35602185 PMCID: PMC9053263 DOI: 10.1038/s43856-021-00030-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 08/10/2021] [Indexed: 01/20/2023] Open
Abstract
Kurtovic et al. highlight some of the recent advances in the development and clinical evaluation of malaria vaccines. The authors outline key vaccine strategies and clinical trials, and discuss priorities for research into the development of an efficacious malaria vaccine.
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38
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Opi DH, Boyle MJ, McLean ARD, Reiling L, Chan JA, Stanisic DI, Ura A, Mueller I, Fowkes FJI, Rogerson SJ, Beeson JG. Reduced risk of placental parasitemia associated with complement fixation on Plasmodium falciparum by antibodies among pregnant women. BMC Med 2021; 19:201. [PMID: 34425801 PMCID: PMC8383393 DOI: 10.1186/s12916-021-02061-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 07/13/2021] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND The pathogenesis of malaria in pregnancy (MiP) involves accumulation of P. falciparum-infected red blood cells (pRBCs) in the placenta, contributing to poor pregnancy outcomes. Parasite accumulation is primarily mediated by P. falciparum erythrocyte membrane protein 1 (PfEMP1). Magnitude of IgG to pRBCs has been associated with reduced risk of MiP in some studies, but associations have been inconsistent. Further, antibody effector mechanisms are poorly understood, and the role of antibody complement interactions is unknown. METHODS Studying a longitudinal cohort of pregnant women (n=302) from a malaria-endemic province in Papua New Guinea (PNG), we measured the ability of antibodies to fix and activate complement using placental binding pRBCs and PfEMP1 recombinant domains. We determined antibody-mediated complement inhibition of pRBC binding to the placental receptor, chondroitin sulfate A (CSA), and associations with protection against placental parasitemia. RESULTS Some women acquired antibodies that effectively promoted complement fixation on placental-binding pRBCs. Complement fixation correlated with IgG1 and IgG3 antibodies, which dominated the response. There was, however, limited evidence for membrane attack complex activity or pRBC lysis or killing. Importantly, a higher magnitude of complement fixing antibodies was prospectively associated with reduced odds of placental infection at delivery. Using genetically modified P. falciparum and recombinant PfEMP1 domains, we found that complement-fixing antibodies primarily targeted a specific variant of PfEMP1 (known as VAR2CSA). Furthermore, complement enhanced the ability of antibodies to inhibit pRBC binding to CSA, which was primarily mediated by complement C1q protein. CONCLUSIONS These findings provide new insights into mechanisms mediating immunity to MiP and reveal potential new strategies for developing malaria vaccines that harness antibody-complement interactions.
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Affiliation(s)
- D Herbert Opi
- Burnet Institute, 85 Commercial Road, Melbourne, Victoria, 3004, Australia. .,Department of Immunology, Monash University, Melbourne, Australia. .,Department of Medicine at the Doherty Institute, University of Melbourne, Melbourne, Australia.
| | - Michelle J Boyle
- Burnet Institute, 85 Commercial Road, Melbourne, Victoria, 3004, Australia.,Human Malaria Immunology Laboratory, QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | | | - Linda Reiling
- Burnet Institute, 85 Commercial Road, Melbourne, Victoria, 3004, Australia
| | - Jo-Anne Chan
- Burnet Institute, 85 Commercial Road, Melbourne, Victoria, 3004, Australia.,Department of Immunology, Monash University, Melbourne, Australia.,Department of Medicine at the Doherty Institute, University of Melbourne, Melbourne, Australia
| | - Danielle I Stanisic
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea.,Institute for Glycomics, Griffith University, Southport, Queensland, Australia
| | - Alice Ura
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Ivo Mueller
- Walter and Eliza Hall Institute of Medical Research, Parkville, Australia.,Department of Medical Biology, University of Melbourne, Melbourne, Australia.,Institute Pasteur, Paris, France
| | - Freya J I Fowkes
- Burnet Institute, 85 Commercial Road, Melbourne, Victoria, 3004, Australia.,Department of Infectious Diseases, Monash University, Melbourne, Australia.,Centre for Epidemiology and Biostatistics, University of Melbourne, Melbourne, Australia.,Department of Epidemiology and Preventative Medicine, Monash University, Melbourne, Australia
| | - Stephen J Rogerson
- Department of Medicine at the Doherty Institute, University of Melbourne, Melbourne, Australia
| | - James G Beeson
- Burnet Institute, 85 Commercial Road, Melbourne, Victoria, 3004, Australia. .,Department of Immunology, Monash University, Melbourne, Australia. .,Department of Medicine at the Doherty Institute, University of Melbourne, Melbourne, Australia. .,Department of Microbiology, Monash University, Clayton, Australia.
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Neutrophils dominate in opsonic phagocytosis of P. falciparum blood-stage merozoites and protect against febrile malaria. Commun Biol 2021; 4:984. [PMID: 34413459 PMCID: PMC8376957 DOI: 10.1038/s42003-021-02511-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 07/27/2021] [Indexed: 12/29/2022] Open
Abstract
Antibody-mediated opsonic phagocytosis (OP) of Plasmodium falciparum blood-stage merozoites has been associated with protection against malaria. However, the precise contribution of different peripheral blood phagocytes in the OP mechanism remains unknown. Here, we developed an in vitro OP assay using peripheral blood leukocytes that allowed us to quantify the contribution of each phagocytic cell type in the OP of merozoites. We found that CD14 + +CD16- monocytes were the dominant phagocytic cells at very low antibody levels and Fc gamma receptor (FcγR) IIA plays a key role. At higher antibody levels however, neutrophils were the main phagocytes in the OP of merozoites with FcγRIIIB acting synergistically with FcγRIIA in the process. We found that OP activity by neutrophils was strongly associated with protection against febrile malaria in longitudinal cohort studies performed in Ghana and India. Our results demonstrate that peripheral blood neutrophils are the main phagocytes of P. falciparum blood-stage merozoites.
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40
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Naturally Acquired Antibodies against Plasmodium falciparum: Friend or Foe? Pathogens 2021; 10:pathogens10070832. [PMID: 34357982 PMCID: PMC8308493 DOI: 10.3390/pathogens10070832] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Revised: 06/28/2021] [Accepted: 06/30/2021] [Indexed: 11/17/2022] Open
Abstract
Antibodies are central to acquired immunity against malaria. Plasmodium falciparum elicits antibody responses against many of its protein components, but there is also formation of antibodies against different parts of the red blood cells, in which the parasites spend most of their time. In the absence of a decisive intervention such as a vaccine, people living in malaria endemic regions largely depend on naturally acquired antibodies for protection. However, these antibodies do not confer sterile immunity and the mechanisms of action are still unclear. Most studies have focused on the inhibitory effect of antibodies, but here, we review both the beneficial as well as the potentially harmful roles of naturally acquired antibodies, as well as autoantibodies formed in malaria. We discuss different studies that have sought to understand acquired antibody responses against P. falciparum antigens, and potential problems when different antibodies are combined, such as in naturally acquired immunity.
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41
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Rathnayake D, Aitken EH, Rogerson SJ. Beyond Binding: The Outcomes of Antibody-Dependent Complement Activation in Human Malaria. Front Immunol 2021; 12:683404. [PMID: 34168652 PMCID: PMC8217965 DOI: 10.3389/fimmu.2021.683404] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2021] [Accepted: 05/24/2021] [Indexed: 11/13/2022] Open
Abstract
Antibody immunity against malaria is effective but non-sterile. In addition to antibody-mediated inhibition, neutralisation or opsonisation of malaria parasites, antibody-mediated complement activation is also important in defense against infection. Antibodies form immune complexes with parasite-derived antigens that can activate the classical complement pathway. The complement system provides efficient surveillance for infection, and its activation leads to parasite lysis or parasite opsonisation for phagocytosis. The induction of complement-fixing antibodies contributes significantly to the development of protective immunity against clinical malaria. These complement-fixing antibodies can form immune complexes that are recognised by complement receptors on innate cells of the immune system. The efficient clearance of immune complexes is accompanied by complement receptor internalisation, abrogating the detrimental consequences of excess complement activation. Here, we review the mechanisms of activation of complement by alternative, classical, and lectin pathways in human malaria at different stages of the Plasmodium life cycle with special emphasis on how complement-fixing antibodies contribute to protective immunity. We briefly touch upon the action of anaphylatoxins, the assembly of membrane attack complex, and the possible reasons underlying the resistance of infected erythrocytes towards antibody-mediated complement lysis, relevant to their prolonged survival in the blood of the human host. We make suggestions for further research on effector functions of antibody-mediated complement activation that would guide future researchers in deploying complement-fixing antibodies in preventive or therapeutic strategies against malaria.
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Affiliation(s)
| | | | - Stephen J. Rogerson
- Department of Infectious Diseases, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia
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Hietanen J, Chim-Ong A, Sattabongkot J, Nguitragool W. Naturally induced humoral response against Plasmodium vivax reticulocyte binding protein 2P1. Malar J 2021; 20:246. [PMID: 34082763 PMCID: PMC8173506 DOI: 10.1186/s12936-021-03784-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 05/25/2021] [Indexed: 11/28/2022] Open
Abstract
Background Plasmodium vivax is the most prevalent malaria parasite in many countries. A better understanding of human immunity to this parasite can provide new insights for vaccine development. Plasmodium vivax Reticulocyte Binding Proteins (RBPs) are key parasite proteins that interact with human proteins during erythrocyte invasion and are targets of the human immune response. The aim of this study is to characterize the human antibody response to RBP2P1, the most recently described member of the RBP family. Methods The levels of total IgG and IgM against RBP2P1 were measured using plasmas from 68 P. vivax malaria patients and 525 villagers in a malarious village of western Thailand. The latter group comprises asymptomatic carriers and healthy uninfected individuals. Subsets of plasma samples were evaluated for anti-RBP2P1 IgG subtypes and complement-fixing activity. Results As age increased, it was found that the level of anti-RBP2P1 IgG increased while the level of IgM decreased. The main anti-RBP2P1 IgG subtypes were IgG1 and IgG3. The IgG3-seropositive rate was higher in asymptomatic carriers than in patients. The higher level of IgG3 was correlated with higher in vitro RBP2P1-mediated complement fixing activity. Conclusions In natural infection, the primary IgG response to RBP2P1 was IgG1 and IgG3. The predominance of these cytophilic subtypes and the elevated level of IgG3 correlating with complement fixing activity, suggest a possible role of anti-RBP2P1 antibodies in immunity against P. vivax.
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Affiliation(s)
- Jenni Hietanen
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, 420/6 Ratchawithi Road, Ratchathewi, 10400, Bangkok, Thailand
| | - Anongruk Chim-Ong
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, 420/6 Ratchawithi Road, Ratchathewi, 10400, Bangkok, Thailand
| | - Jetsumon Sattabongkot
- Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, 420/6 Ratchawithi Road, Ratchathewi, 10400, Bangkok, Thailand
| | - Wang Nguitragool
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, 420/6 Ratchawithi Road, Ratchathewi, 10400, Bangkok, Thailand.
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Soon MSF, Nalubega M, Boyle MJ. T-follicular helper cells in malaria infection and roles in antibody induction. OXFORD OPEN IMMUNOLOGY 2021; 2:iqab008. [PMID: 36845571 PMCID: PMC9914587 DOI: 10.1093/oxfimm/iqab008] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 03/03/2021] [Accepted: 03/08/2021] [Indexed: 01/29/2023] Open
Abstract
Immunity to malaria is mediated by antibodies that block parasite replication to limit parasite burden and prevent disease. Cytophilic antibodies have been consistently shown to be associated with protection, and recent work has improved our understanding of the direct and Fc-mediated mechanisms of protective antibodies. Antibodies also have important roles in vaccine-mediated immunity. Antibody induction is driven by the specialized CD4+ T cells, T-follicular helper (Tfh) cells, which function within the germinal centre to drive B-cell activation and antibody induction. In humans, circulating Tfh cells can be identified in peripheral blood and are differentiated into subsets that appear to have pathogen/vaccination-specific roles in antibody induction. Tfh cell responses are essential for protective immunity from Plasmodium infection in murine models of malaria. Our understanding of the activation of Tfh cells during human malaria infection and the importance of different Tfh cell subsets in antibody development is still emerging. This review will discuss our current knowledge of Tfh cell activation and development in malaria, and the potential avenues and pitfalls of targeting Tfh cells to improve malaria vaccines.
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Affiliation(s)
- Megan S F Soon
- Department of Infectious Diseases, QIMR-Berghofer, 300 Herston Road, Herston, QLD, 4006, Australia
| | - Mayimuna Nalubega
- Infectious Diseases Research Collaboration, Tororo District Hospital, Tororo, Uganda
| | - Michelle J Boyle
- Department of Infectious Diseases, QIMR-Berghofer, 300 Herston Road, Herston, QLD, 4006, Australia,Correspondence address. QIMR Berghofer Medical Research Institute, Brisbane, Australia. E-mail:
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Kurtovic L, Wetzel D, Reiling L, Drew DR, Palmer C, Kouskousis B, Hanssen E, Wines BD, Hogarth PM, Suckow M, Jenzelewski V, Piontek M, Chan JA, Beeson JG. Novel Virus-Like Particle Vaccine Encoding the Circumsporozoite Protein of Plasmodium falciparum Is Immunogenic and Induces Functional Antibody Responses in Mice. Front Immunol 2021; 12:641421. [PMID: 33815393 PMCID: PMC8010251 DOI: 10.3389/fimmu.2021.641421] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 03/01/2021] [Indexed: 01/10/2023] Open
Abstract
RTS,S is the leading malaria vaccine in development, but has demonstrated only moderate protective efficacy in clinical trials. RTS,S is a virus-like particle (VLP) that uses the human hepatitis B virus as scaffold to display the malaria sporozoite antigen, circumsporozoite protein (CSP). Particle formation requires four-fold excess scaffold antigen, and as a result, CSP represents only a small portion of the final vaccine construct. Alternative VLP or nanoparticle platforms that reduce the amount of scaffold antigen and increase the amount of the target CSP antigen present in particles may enhance vaccine immunogenicity and efficacy. Here, we describe the production and characterization of a novel VLP that uses the small surface antigen (dS) of duck hepatitis B virus to display CSP. The CSP-dS fusion protein successfully formed VLPs without the need for excess scaffold antigen, and thus CSP represented a larger portion of the vaccine construct. CSP-dS formed large particles approximately 31-74 nm in size and were confirmed to display CSP on the surface. CSP-dS VLPs were highly immunogenic in mice and induced antibodies to multiple regions of CSP, even when administered at a lower vaccine dosage. Vaccine-induced antibodies demonstrated relevant functional activities, including Fc-dependent interactions with complement and Fcγ-receptors, previously identified as important in malaria immunity. Further, vaccine-induced antibodies had similar properties (epitope-specificity and avidity) to monoclonal antibodies that are protective in mouse models. Our novel platform to produce VLPs without excess scaffold protein has wide implications for the future development of vaccines for malaria and other infectious diseases.
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Affiliation(s)
- Liriye Kurtovic
- Life Sciences, Burnet Institute, Melbourne, VIC, Australia
- Departments of Immunology and Pathology and Infectious Diseases, Central Clinical School, Monash University, Melbourne, VIC, Australia
| | | | - Linda Reiling
- Life Sciences, Burnet Institute, Melbourne, VIC, Australia
| | - Damien R. Drew
- Life Sciences, Burnet Institute, Melbourne, VIC, Australia
| | | | | | - Eric Hanssen
- The Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC, Australia
| | - Bruce D. Wines
- Life Sciences, Burnet Institute, Melbourne, VIC, Australia
- Departments of Immunology and Pathology and Infectious Diseases, Central Clinical School, Monash University, Melbourne, VIC, Australia
- Clinical Pathology, The University of Melbourne, Parkville, VIC, Australia
| | - P. Mark Hogarth
- Life Sciences, Burnet Institute, Melbourne, VIC, Australia
- Departments of Immunology and Pathology and Infectious Diseases, Central Clinical School, Monash University, Melbourne, VIC, Australia
- Clinical Pathology, The University of Melbourne, Parkville, VIC, Australia
| | | | | | | | - Jo-Anne Chan
- Life Sciences, Burnet Institute, Melbourne, VIC, Australia
- Departments of Immunology and Pathology and Infectious Diseases, Central Clinical School, Monash University, Melbourne, VIC, Australia
- Department of Medicine, Royal Melbourne Hospital, The University of Melbourne, Parkville, VIC, Australia
| | - James G. Beeson
- Life Sciences, Burnet Institute, Melbourne, VIC, Australia
- Departments of Immunology and Pathology and Infectious Diseases, Central Clinical School, Monash University, Melbourne, VIC, Australia
- Department of Medicine, Royal Melbourne Hospital, The University of Melbourne, Parkville, VIC, Australia
- Department of Microbiology, Monash University, Clayton, VIC, Australia
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Liposome engraftment and antigen combination potentiate the immune response towards conserved epitopes of the malaria vaccine candidate MSP2. Vaccine 2021; 39:1746-1757. [PMID: 33618946 DOI: 10.1016/j.vaccine.2021.02.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 01/30/2021] [Accepted: 02/06/2021] [Indexed: 11/23/2022]
Abstract
Merozoite surface protein 2 (MSP2) is a highly abundant, GPI-anchored surface antigen on merozoites of the malaria parasite Plasmodium falciparum. It consists of highly conserved N- and C-terminal domains, and a central polymorphic region that allows all MSP2 alleles to be categorized into the 3D7 or FC27 family. Previously it has been shown that epitope accessibility differs between lipid-bound and lipid-free MSP2, suggesting that lipid interactions modulate the conformation and antigenicity in a way that may better mimic native MSP2 on the merozoite surface. Therefore, we have immunised mice with MSP2 engrafted onto liposomes using a C-terminal tether that mimics the native GPI anchor. To improve the immunogenicity of the formulated antigen, liposomes were supplemented with Pathogen Associated Molecular Pattern molecules, specifically agonists of the Toll-like receptor 4 (TLR4) or TLR2. Induced antibodies were directed mostly towards conserved epitopes, predominantly in the conserved C-terminal region of MSP2. We also found that immunisation with a combination of 3D7 and FC27 MSP2 enhanced antibody responses to conserved epitopes, and that the overall responses of mice immunised with MSP2-engrafted liposomes were comparable in magnitude to those of mice immunised with MSP2 formulated in Montanide ISA720. The antibodies elicited in mice by immunising with MSP2-engrafted liposomes recognised the native form of parasite MSP2 on western blots and were found to be cross-reactive with isolated 3D7 and FC27 merozoites when investigated by ELISA. The liposome-tethered MSP2 induced higher titres of complement-fixing antibodies to 3D7 and FC27 MSP2 than did MSP2 formulated in Montanide ISA720. Our results indicate that liposomal formulation represents a viable strategy for eliciting a strong immune response that favours conserved epitopes in MSP2 and thus a strain-transcendent immune response.
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Th2-like T Follicular Helper Cells Promote Functional Antibody Production during Plasmodium falciparum Infection. CELL REPORTS MEDICINE 2020; 1:100157. [PMID: 33377128 PMCID: PMC7762767 DOI: 10.1016/j.xcrm.2020.100157] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 09/08/2020] [Accepted: 11/19/2020] [Indexed: 01/10/2023]
Abstract
CD4+ T follicular helper cells (Tfh) are key drivers of antibody development. During Plasmodium falciparum malaria in children, the activation of Tfh is restricted to the Th1 subset and not associated with antibody levels. To identify Tfh subsets that are associated with antibody development in malaria, we assess Tfh and antibodies longitudinally in human volunteers with experimental P. falciparum infection. Tfh cells activate during infection, with distinct dynamics in different Tfh subsets. Th2-Tfh cells activate early, during peak infection, while Th1-Tfh cells activate 1 week after peak infection and treatment. Th2-Tfh cell activation is associated with the functional breadth and magnitude of parasite antibodies. In contrast, Th1-Tfh activation is not associated with antibody development but instead with plasma cells, which have previously been shown to play a detrimental role in the development of long-lived immunity. Thus, our study identifies the contrasting roles of Th2 and Th1-Tfh cells during experimental P. falciparum malaria.
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Wiebe MC, Yanow SK. Do Antibodies to Malaria Surface Antigens Play a Role in Protecting Mothers From Maternal Anemia? Front Immunol 2020; 11:609957. [PMID: 33391279 PMCID: PMC7775498 DOI: 10.3389/fimmu.2020.609957] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 11/17/2020] [Indexed: 11/13/2022] Open
Abstract
Pregnancy-associated malaria (PAM) caused by Plasmodium falciparum can result in detrimental outcomes for both mother and infant, including low infant birth weight, preterm birth, maternal anemia, spontaneous abortion, and maternal and/or infant mortality. Maternal anemia is a particularly complex outcome, as the body must both maintain erythropoiesis and tolerance of the growing fetus, while directing a Th1 response against the parasite. Underlying the pathogenesis of PAM is the expression of variant surface antigens (VSAPAM) on the surface of infected red blood cells (iRBC) that mediate sequestration of the iRBC in the placenta. Naturally acquired antibodies to VSAPAM can block sequestration and activate opsonic phagocytosis, both associated with improved pregnancy outcomes. In this review, we ask whether VSAPAM antibodies can also protect mothers against malarial anemia. Studies were identified where VSAPAM antibody titres and/or function were associated with higher maternal hemoglobin levels, thus supporting additional protective mechanisms for these antibodies against PAM. Yet these associations were not widely observed, and many studies reported no association between protection from maternal anemia and VSAPAM antibodies. We discuss the epidemiological, biological and technical factors that may explain some of the variability among these studies. We appraise the current evidence of these complex interactions between PAM-specific immunity and maternal anemia, propose potential mechanisms, and discuss knowledge gaps.
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Affiliation(s)
- Madeleine C Wiebe
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada
| | - Stephanie K Yanow
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada.,School of Public Health, University of Alberta, Edmonton, AB, Canada
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Kurtovic L, Beeson JG. Complement Factors in COVID-19 Therapeutics and Vaccines. Trends Immunol 2020; 42:94-103. [PMID: 33402318 PMCID: PMC7733687 DOI: 10.1016/j.it.2020.12.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 11/30/2020] [Accepted: 12/04/2020] [Indexed: 12/18/2022]
Abstract
Complement is integral to a healthy functioning immune system and orchestrates various innate and adaptive responses against viruses and other pathogens. Despite its importance, the potential beneficial role of complement in immunity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been overshadowed by reports of extensive complement activation in severe coronavirus disease 2019 (COVID-19) patients. Here, we hypothesize that complement may also have a protective role and could function to enhance virus neutralization by antibodies, promote virus phagocytosis by immune cells, and lysis of virus. These functions might be exploited in the development of effective therapeutics and vaccines against SARS-CoV-2. Complement has been implicated in playing some role in severe COVID-19 pathogenesis. However, the evidence to support this is largely inferred from case–control studies. The potential protective role of complement has been largely ignored, which might contribute to innate and adaptive immunity against SARS-CoV-2 infection. Immunity to many pathogens relies on complement to enhance antibody-mediated neutralization and mediate phagocytosis and lysis. These mechanisms might also contribute to immunity against SARS-CoV-2 infection, and complement might be potentially exploited in antibody-based therapeutics and vaccines. Careful selection of vaccine adjuvants and epitopes included in vaccine constructs can influence whether vaccine-induced antibodies activate complement. Mutations in monoclonal antibodies can be used to promote hexamer formation between antibodies, which can significantly improve complement binding and activation.
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Affiliation(s)
- Liriye Kurtovic
- Burnet Institute, Melbourne, Australia; Department of Immunology and Pathology, Monash University, Melbourne, Australia
| | - James G Beeson
- Burnet Institute, Melbourne, Australia; Department of Immunology and Pathology, Monash University, Melbourne, Australia; Central Clinical School and Department of Microbiology, Monash University, Melbourne, Australia; Department of Medicine, The University of Melbourne, Parkville, Australia.
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Ashley EA, Yeka A. Seasonal malaria chemoprevention: closing the know-do gap. Lancet 2020; 396:1778-1779. [PMID: 33278921 DOI: 10.1016/s0140-6736(20)32525-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 11/18/2020] [Indexed: 11/30/2022]
Affiliation(s)
- Elizabeth A Ashley
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit, Microbiology Laboratory, Mahosot Hospital, Vientiane 01000, Laos; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
| | - Adoke Yeka
- College of Health Sciences, Makerere University, Kampala, Uganda; Infectious Diseases Research Collaboration, Kampala, Uganda
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Kaslow DC. Malaria vaccine research & innovation: the intersection of IA2030 and zero malaria. NPJ Vaccines 2020; 5:109. [PMID: 33298967 PMCID: PMC7677906 DOI: 10.1038/s41541-020-00259-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Accepted: 10/30/2020] [Indexed: 12/17/2022] Open
Affiliation(s)
- David C Kaslow
- PATH, 2201 Westlake Avenue, Suite 200, Seattle, WA, 98121, USA.
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