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Miura K, Deng B, Varadharajan Suresh R, Gebremicale YT, Zhou L, Pham TP, Roche K, Diouf A, Lovell JF, Julien JP, Long CA. A human-serum-free medium can induce more infectious P. falciparum gametocytes than a conventional human-serum-containing medium. Sci Rep 2024; 14:22052. [PMID: 39333737 PMCID: PMC11436888 DOI: 10.1038/s41598-024-73843-5] [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: 06/14/2024] [Accepted: 09/20/2024] [Indexed: 09/30/2024] Open
Abstract
Malaria remains a global health problem, and the standard membrane feeding assay (SMFA) is a key functional assay for development of new interventions to stop malaria transmission from human to mosquito. For SMFA, media with ~ 10% of human serum has been used for infectious gametocyte cultures, however, there are multiple challenges to obtain a suitable human serum. Here we show a human-serum-free culture medium (HSF), which was a mixture of two stem cell culture media and AlbuMAX, supported infectious gametocyte growth. Moreover, the HSF-induced gametocytes elicited significantly higher numbers of oocysts compared to gametocytes cultured with conventional human serum medium (Conv). While some caution is required when comparing percent transmission reducing activity data generated from HSF-SMFA and Conv-SMFA, the HSF method can facilitate the establishment of gametocyte cultures or SMFA by bypassing the need for human serum. Thus, this study will support future development of P. falciparum transmission-blocking interventions.
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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.
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 12735 Twinbrook Parkway, Rockville, MD, 20852, USA.
| | - Bingbing Deng
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, 20852, USA
| | - Ragavan Varadharajan Suresh
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, 20852, USA
- Academic Programs, the Foundation for Advanced Education in the Sciences, Bethesda, MD, 20892, USA
| | - Yonas T Gebremicale
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, 20852, USA
| | - Luwen Zhou
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, 20852, USA
| | - Thao P Pham
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, 20852, USA
| | - Kyle Roche
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, 20852, USA
| | - Ababacar Diouf
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, 20852, USA
| | - Jonathan F Lovell
- Department of Biomedical Engineering, University at Buffalo, State University of New York, Buffalo, NY, 14260, USA
| | - Jean-Philippe Julien
- Program in Molecular Medicine, The Hospital for Sick Children Research Institute, Toronto, ON, M5G 0A4, Canada
- Departments of Biochemistry and Immunology, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Carole A Long
- 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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2
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Tang WK, Salinas ND, Kolli SK, Xu S, Urusova DV, Kumar H, Jimah JR, Subramani PA, Ogbondah MM, Barnes SJ, Adams JH, Tolia NH. Multistage protective anti-CelTOS monoclonal antibodies with cross-species sterile protection against malaria. Nat Commun 2024; 15:7487. [PMID: 39209843 PMCID: PMC11362571 DOI: 10.1038/s41467-024-51701-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Accepted: 08/15/2024] [Indexed: 09/04/2024] Open
Abstract
CelTOS is a malaria vaccine antigen that is conserved in Plasmodium and other apicomplexan parasites and plays a role in cell-traversal. The structural basis and mechanisms of CelTOS-induced protective immunity to parasites are unknown. Here, CelTOS-specific monoclonal antibodies (mAbs) 7g7 and 4h12 demonstrated multistage activity, protecting against liver infection and preventing parasite transmission to mosquitoes. Both mAbs demonstrated cross-species activity with sterile protection against in vivo challenge with transgenic parasites containing either P. falciparum or P. vivax CelTOS, and with transmission reducing activity against P. falciparum. The mAbs prevented CelTOS-mediated pore formation providing insight into the protective mechanisms. X-ray crystallography and mutant-library epitope mapping revealed two distinct broadly conserved neutralizing epitopes. 7g7 bound to a parallel dimer of CelTOS, while 4h12 bound to a novel antiparallel dimer architecture. These findings inform the design of antibody therapies and vaccines and raise the prospect of a single intervention to simultaneously combat P. falciparum and P. vivax malaria.
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MESH Headings
- Antibodies, Monoclonal/immunology
- Animals
- Plasmodium falciparum/immunology
- Plasmodium vivax/immunology
- Malaria Vaccines/immunology
- Antibodies, Protozoan/immunology
- Mice
- Malaria, Falciparum/immunology
- Malaria, Falciparum/prevention & control
- Malaria, Falciparum/parasitology
- Crystallography, X-Ray
- Epitopes/immunology
- Malaria, Vivax/prevention & control
- Malaria, Vivax/immunology
- Malaria, Vivax/parasitology
- Antigens, Protozoan/immunology
- Humans
- Female
- Epitope Mapping
- Malaria/immunology
- Malaria/prevention & control
- Malaria/parasitology
- Mice, Inbred BALB C
- Protozoan Proteins/immunology
- Protozoan Proteins/chemistry
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Affiliation(s)
- Wai Kwan Tang
- Host‒Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Nichole D Salinas
- Host‒Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Surendra Kumar Kolli
- Center of Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, Tampa, FL, USA
| | - Shulin Xu
- Center of Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, Tampa, FL, USA
| | - Darya V Urusova
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Hirdesh Kumar
- Host‒Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - John R Jimah
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO, USA
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| | - Pradeep Annamalai Subramani
- Center of Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, Tampa, FL, USA
| | - Madison M Ogbondah
- Center of Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, Tampa, FL, USA
| | - Samantha J Barnes
- Center of Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, Tampa, FL, USA
| | - John H Adams
- Center of Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, Tampa, FL, USA
| | - Niraj H Tolia
- Host‒Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA.
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3
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Appetecchia F, Fabbrizi E, Fiorentino F, Consalvi S, Biava M, Poce G, Rotili D. Transmission-Blocking Strategies for Malaria Eradication: Recent Advances in Small-Molecule Drug Development. Pharmaceuticals (Basel) 2024; 17:962. [PMID: 39065810 PMCID: PMC11279868 DOI: 10.3390/ph17070962] [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: 06/11/2024] [Revised: 07/11/2024] [Accepted: 07/17/2024] [Indexed: 07/28/2024] Open
Abstract
Malaria drug research and development efforts have resurged in the last decade following the decelerating rate of mortality and malaria cases in endemic regions. The inefficiency of malaria interventions is largely driven by the spreading resistance of the Plasmodium falciparum parasite to current drug regimens and that of the malaria vector, the Anopheles mosquito, to insecticides. In response to the new eradication agenda, drugs that act by breaking the malaria transmission cycle (transmission-blocking drugs), which has been recognized as an important and additional target for intervention, are being developed. These drugs take advantage of the susceptibility of Plasmodium during population bottlenecks before transmission (gametocytes) and in the mosquito vector (gametes, zygotes, ookinetes, oocysts, sporozoites). To date, compounds targeting stage V gametocytes predominate in the chemical library of transmission-blocking drugs, and some of them have entered clinical trials. The targeting of Plasmodium mosquito stages has recently renewed interest in the development of innovative malaria control tools, which hold promise for the application of compounds effective at these stages. In this review, we highlight the major achievements and provide an update on the research of transmission-blocking drugs, with a particular focus on their chemical scaffolds, antiplasmodial activity, and transmission-blocking potential.
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Affiliation(s)
| | | | | | | | | | - Giovanna Poce
- Department of Drug Chemistry and Technologies, Sapienza University of Rome, P.le A. Moro 5, 00185 Rome, Italy; (F.A.); (E.F.); (F.F.); (S.C.); (M.B.)
| | - Dante Rotili
- Department of Drug Chemistry and Technologies, Sapienza University of Rome, P.le A. Moro 5, 00185 Rome, Italy; (F.A.); (E.F.); (F.F.); (S.C.); (M.B.)
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4
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Duffy PE, Gorres JP, Healy SA, Fried M. Malaria vaccines: a new era of prevention and control. Nat Rev Microbiol 2024:10.1038/s41579-024-01065-7. [PMID: 39025972 DOI: 10.1038/s41579-024-01065-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/30/2024] [Indexed: 07/20/2024]
Abstract
Malaria killed over 600,000 people in 2022, a death toll that has not improved since 2015. Additionally, parasites and mosquitoes resistant to existing interventions are spreading across Africa and other regions. Vaccines offer hope to reduce the mortality burden: the first licensed malaria vaccines, RTS,S and R21, will be widely deployed in 2024 and should substantially reduce childhood deaths. In this Review, we provide an overview of the malaria problem and the Plasmodium parasite, then describe the RTS,S and R21 vaccines (the first vaccines for any human parasitic disease), summarizing their benefits and limitations. We explore next-generation vaccines designed using new knowledge of malaria pathogenesis and protective immunity, which incorporate antigens and platforms to elicit effective immune responses against different parasite stages in human or mosquito hosts. We describe a decision-making process that prioritizes malaria vaccine candidates for development in a resource-constrained environment. Future vaccines might improve upon the protective efficacy of RTS,S or R21 for children, or address the wider malaria scourge by preventing pregnancy malaria, reducing the burden of Plasmodium vivax or accelerating malaria elimination.
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Affiliation(s)
- Patrick E Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA.
| | - J Patrick Gorres
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Sara A Healy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Michal Fried
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
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Salinas ND, Ma R, McAleese H, Ouahes T, Long CA, Miura K, Lambert LE, Tolia NH. A Self-Assembling Pfs230D1-Ferritin Nanoparticle Vaccine Has Potent and Durable Malaria Transmission-Reducing Activity. Vaccines (Basel) 2024; 12:546. [PMID: 38793797 PMCID: PMC11125772 DOI: 10.3390/vaccines12050546] [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: 04/12/2024] [Revised: 05/10/2024] [Accepted: 05/14/2024] [Indexed: 05/26/2024] Open
Abstract
Malaria is caused by eukaryotic protozoan parasites of the genus Plasmodium. There are 249 million new cases and 608,000 deaths annually, and new interventions are desperately needed. Malaria vaccines can be divided into three categories: liver stage, blood stage, or transmission-blocking vaccines. Transmission-blocking vaccines prevent the transmission of disease by the mosquito vector from one human to another. Pfs230 is one of the leading transmission-blocking vaccine antigens for malaria. Here, we describe the development of a 24-copy self-assembling nanoparticle vaccine comprising domain 1 of Pfs230 genetically fused to H. pylori ferritin. The single-component Pfs230D1-ferritin construct forms a stable and homogenous 24-copy nanoparticle with good production yields. The nanoparticle is highly immunogenic, as two low-dose vaccinations of New Zealand White rabbits elicited a potent and durable antibody response with high transmission-reducing activity when formulated in two distinct adjuvants suitable for translation to human use. This single-component 24-copy Pfs230D1-ferritin nanoparticle vaccine has the potential to improve production pipelines and the cost of manufacturing a potent and durable transmission-blocking vaccine for malaria control.
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Affiliation(s)
- Nichole D. Salinas
- Host-Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA; (N.D.S.)
| | - Rui Ma
- Host-Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA; (N.D.S.)
| | - Holly McAleese
- Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Tarik Ouahes
- Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Carole A. Long
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Kazutoyo Miura
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Lynn E. Lambert
- Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Niraj H. Tolia
- Host-Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA; (N.D.S.)
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Yamamoto Y, Fabbri C, Okuhara D, Takagi R, Kawabata Y, Katayama T, Iyori M, Hasyim AA, Sakamoto A, Mizukami H, Shida H, Lopes S, Yoshida S. A two-dose viral-vectored Plasmodium vivax multistage vaccine confers durable protection and transmission-blockade in a pre-clinical study. Front Immunol 2024; 15:1372584. [PMID: 38745665 PMCID: PMC11091281 DOI: 10.3389/fimmu.2024.1372584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Accepted: 04/12/2024] [Indexed: 05/16/2024] Open
Abstract
Among Plasmodium spp. responsible for human malaria, Plasmodium vivax ranks as the second most prevalent and has the widest geographical range; however, vaccine development has lagged behind that of Plasmodium falciparum, the deadliest Plasmodium species. Recently, we developed a multistage vaccine for P. falciparum based on a heterologous prime-boost immunization regimen utilizing the attenuated vaccinia virus strain LC16m8Δ (m8Δ)-prime and adeno-associated virus type 1 (AAV1)-boost, and demonstrated 100% protection and more than 95% transmission-blocking (TB) activity in the mouse model. In this study, we report the feasibility and versatility of this vaccine platform as a P. vivax multistage vaccine, which can provide 100% sterile protection against sporozoite challenge and >95% TB efficacy in the mouse model. Our vaccine comprises m8Δ and AAV1 viral vectors, both harboring the gene encoding two P. vivax circumsporozoite (PvCSP) protein alleles (VK210; PvCSP-Sal and VK247; -PNG) and P25 (Pvs25) expressed as a Pvs25-PvCSP fusion protein. For protective efficacy, the heterologous m8Δ-prime/AAV1-boost immunization regimen showed 100% (short-term; Day 28) and 60% (long-term; Day 242) protection against PvCSP VK210 transgenic Plasmodium berghei sporozoites. For TB efficacy, mouse sera immunized with the vaccine formulation showed >75% TB activity and >95% transmission reduction activity by a direct membrane feeding assay using P. vivax isolates in blood from an infected patient from the Brazilian Amazon region. These findings provide proof-of-concept that the m8Δ/AAV1 vaccine platform is sufficiently versatile for P. vivax vaccine development. Future studies are needed to evaluate the safety, immunogenicity, vaccine efficacy, and synergistic effects on protection and transmission blockade in a non-human primate model for Phase I trials.
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Affiliation(s)
- Yutaro Yamamoto
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa University, Kanazawa, Ishikawa, Japan
| | - Camila Fabbri
- Instituto Leônidas & Maria Deane/Fiocruz Amazônia, Laboratório de Diagnóstico e Controle e Doenças Infecciosas da Amazônia, Manaus, Amazonas, Brazil
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Unidade de Pesquisa Clínica Carlos Borborema - UPCCB, Manaus, Amazonas, Brazil
| | - Daiki Okuhara
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa University, Kanazawa, Ishikawa, Japan
| | - Rina Takagi
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa University, Kanazawa, Ishikawa, Japan
| | - Yuna Kawabata
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa University, Kanazawa, Ishikawa, Japan
| | - Takuto Katayama
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa University, Kanazawa, Ishikawa, Japan
| | - Mitsuhiro Iyori
- Department of Pharmaceutical Sciences, Musashino University, Tokyo, Japan
| | - Ammar A. Hasyim
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa University, Kanazawa, Ishikawa, Japan
| | - Akihiko Sakamoto
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa University, Kanazawa, Ishikawa, Japan
| | - Hiroaki Mizukami
- Division of Genetic Therapeutics, Jichi Medical University, Shimono, Tochigi, Japan
| | - Hisatoshi Shida
- Laboratory of Primate Model, Research Center for Infectious Diseases, Institute for Frontier Life and Medical Science, Kyoto University, Kyoto, Japan
| | - Stefanie Lopes
- Instituto Leônidas & Maria Deane/Fiocruz Amazônia, Laboratório de Diagnóstico e Controle e Doenças Infecciosas da Amazônia, Manaus, Amazonas, Brazil
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Unidade de Pesquisa Clínica Carlos Borborema - UPCCB, Manaus, Amazonas, Brazil
| | - Shigeto Yoshida
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa University, Kanazawa, Ishikawa, Japan
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Balam S, Miura K, Ayadi I, Konaté D, Incandela NC, Agnolon V, Guindo MA, Diakité SA, Olugbile S, Nebie I, Herrera SM, Long C, Kajava AV, Diakité M, Corradin G, Herrera S, Herrera MA. Cross-reactivity of r Pvs48/45, a recombinant Plasmodium vivax protein, with sera from Plasmodium falciparum endemic areas of Africa. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.10.588966. [PMID: 38659832 PMCID: PMC11042229 DOI: 10.1101/2024.04.10.588966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Background Ps48/45, a Plasmodium gametocyte surface protein, is a promising candidate for malaria transmission-blocking (TB) vaccine. Due to its relevance for a multispecies vaccine, we explored the cross-reactivity and TB activity of a recombinant P. vivax Ps48/45 protein (rPvs48/45) with sera from P. falciparum-exposed African donors. Methods rPvs48/45 was produced in Chinese hamster ovary cell lines and tested by ELISA for its cross-reactivity with sera from Burkina Faso, Tanzania, Mali, and Nigeria - In addition, BALB/c mice were immunized with the rPvs48/45 protein formulated in Montanide ISA-51 and inoculated with a crude extract of P. falciparum NF-54 gametocytes to evaluate the parasite-boosting effect on rPvs48/45 antibody titers. Specific anti-rPvs48/45 IgG purified from African sera was used to evaluate the ex vivo TB activity on P. falciparum, using standard mosquito membrane feeding assays (SMFA). Results rPvs48/45 protein showed cross-reactivity with sera of individuals from all four African countries, in proportions ranging from 94% (Tanzania) to 40% (Nigeria). Also, the level of cross-reactive antibodies varied significantly between countries (p<0.0001), with a higher antibody level in Mali and the lowest in Nigeria. In addition, antibody levels were higher in adults (≥ 17 years) than young children (≤ 5 years) in both Mali and Tanzania, with a higher proportion of responders in adults (90%) than in children (61%) (p<0.0001) in Mali, where male (75%) and female (80%) displayed similar antibody responses. Furthermore, immunization of mice with P. falciparum gametocytes boosted anti-Pvs48/45 antibody responses, recognizing P. falciparum gametocytes in indirect immunofluorescence antibody test. Notably, rPvs48/45 affinity-purified African IgG exhibited a TB activity of 61% against P. falciparum in SMFA. Conclusion African sera (exposed only to P. falciparum) cross-recognized the rPvs48/45 protein. This, together with the functional activity of IgG, warrants further studies for the potential development of a P. vivax and P. falciparum cross-protective TB vaccine.
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Affiliation(s)
- Saidou Balam
- International Center for Excellence in Research (ICER-Mali), University of Sciences, Techniques and Technologies of Bamako (USTTB), Bamako, Mali
| | - Kazutoyo Miura
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Imen Ayadi
- Immunobiology Department, University of Lausanne, Lausanne, Switzerland
| | - Drissa Konaté
- International Center for Excellence in Research (ICER-Mali), University of Sciences, Techniques and Technologies of Bamako (USTTB), Bamako, Mali
| | | | - Valentina Agnolon
- Division of Immunology and Allergy, Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne, Switzerland aaaa
| | - Merepen A Guindo
- International Center for Excellence in Research (ICER-Mali), University of Sciences, Techniques and Technologies of Bamako (USTTB), Bamako, Mali
| | - Seidina A.S. Diakité
- International Center for Excellence in Research (ICER-Mali), University of Sciences, Techniques and Technologies of Bamako (USTTB), Bamako, Mali
| | - Sope Olugbile
- Immunobiology Department, University of Lausanne, Lausanne, Switzerland
| | - Issa Nebie
- Groupe de Recherche Action Santé (GRAS), Burkina Faso, West Africa
| | | | - Carole Long
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Andrey V. Kajava
- Montpellier Cell Biology Research Center (CRBM), University of Montpellier, CNRS, France
| | - Mahamadou Diakité
- International Center for Excellence in Research (ICER-Mali), University of Sciences, Techniques and Technologies of Bamako (USTTB), Bamako, Mali
| | | | - Socrates Herrera
- Caucaseco Scientific Research Center, Cali, Colombia
- Malaria Vaccine and Drug Development Center, Cali, Colombia
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8
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Yao G, Min H, Yu X, Liu F, Cui L, Cao Y. A nanoparticle vaccine displaying the ookinete PSOP25 antigen elicits transmission-blocking antibody response against Plasmodium berghei. Parasit Vectors 2023; 16:403. [PMID: 37932796 PMCID: PMC10626823 DOI: 10.1186/s13071-023-06020-8] [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: 07/25/2023] [Accepted: 10/18/2023] [Indexed: 11/08/2023] Open
Abstract
BACKGROUND Safe and effective vaccines are crucial for the control and eventual elimination of malaria. Novel approaches to optimize and improve vaccine efficacy are urgently required. Nanoparticle-based delivery platforms are considered potent and powerful tools for vaccine development. METHODS In this study, we developed a transmission-blocking vaccine against malaria by conjugating the ookinete surface antigen PSOP25 to the Acinetobacter phage coat protein AP205, forming virus-like particles (VLPs) using the SpyTag/SpyCatcher adaptor system. The combination of AP205-2*SpyTag with PSOP25-SpyCatcher resulted in the formation of AP205-PSOP25 complexes (VLP-PSOP25). The antibody titers and avidity of serum from each immunization group were assessed by ELISA. Western blot and IFA were performed to confirm the specific reactivity of the elicit antisera to the native PSOP25 in Plasmodium berghei ookinetes. Both in vitro and in vivo assays were conducted to evaluate the transmission-blocking activity of VLP-PSOP25 vaccine. RESULTS Immunization of mice with VLP-PSOP25 could induced higher levels of high-affinity antibodies than the recombinant PSOP25 (rPSOP25) alone or mixtures of untagged AP205 and rPSOP25 but was comparable to rPSOP25 formulated with alum. Additionally, the VLP-PSOP25 vaccine enhanced Th1-type immune response with remarkably increased levels of IgG2a subclass. The antiserum generated by VLP-PSOP25 specifically recognizes the native PSOP25 antigen in P. berghei ookinetes. Importantly, antisera generated by inoculation with the VLP-PSOP25 could inhibit ookinete development in vitro and reduce the prevalence of infected mosquitoes or oocyst intensity in direct mosquito feeding assays. CONCLUSIONS Antisera elicited by immunization with the VLP-PSOP25 vaccine confer moderate transmission-reducing activity and transmission-blocking activity. Our results support the utilization of the AP205-SpyTag/SpyCatcher platform for next-generation TBVs development.
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Affiliation(s)
- Guixiang Yao
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang, Liaoning, China
| | - Hui Min
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang, Liaoning, China
| | - Xinxin Yu
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang, Liaoning, China
| | - Fei Liu
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang, Liaoning, China
| | - Liwang Cui
- Department of Internal Medicine, Morsani College of Medicine, University of South Florida, 3720 Spectrum Boulevard, Tampa, FL, USA.
| | - Yaming Cao
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang, Liaoning, China.
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9
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Shukla N, Tang WK, Coelho CH, Long CA, Healy SA, Sagara I, Miura K, Duffy PE, Tolia NH. A human antibody epitope map of the malaria vaccine antigen Pfs25. NPJ Vaccines 2023; 8:108. [PMID: 37542029 PMCID: PMC10403551 DOI: 10.1038/s41541-023-00712-z] [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: 03/11/2023] [Accepted: 07/12/2023] [Indexed: 08/06/2023] Open
Abstract
Pfs25 is a leading antigen for a malaria transmission-blocking vaccine and shows moderate transmission-blocking activity and induction of rapidly decreasing antibody titers in clinical trials. A comprehensive definition of all transmission-reducing epitopes of Pfs25 will inform structure-guided design to enhance Pfs25-based vaccines, leading to potent transmission-blocking activity. Here, we compiled a detailed human antibody epitope map comprising epitope binning data and structures of multiple human monoclonal antibodies, including three new crystal structures of Pfs25 in complex with transmission-reducing antibodies from Malian volunteers immunized with Pfs25 conjugated to EPA and adjuvanted with AS01. These structures revealed additional epitopes in Pfs25 capable of reducing transmission and expanded this characterization to malaria-exposed humans. This work informs immunogen design to focus the antibody response to transmission-reducing epitopes of Pfs25, enabling development of more potent transmission-blocking vaccines for malaria.
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Affiliation(s)
- Niharika Shukla
- Host-Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, USA
| | - Wai Kwan Tang
- Host-Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, USA
| | - Camila H Coelho
- Pathogenesis and Immunity Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, USA
- Center for Vaccine Research and Pandemic Preparedness (C-VARPP), Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Carole A Long
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Sara A Healy
- Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, USA
| | - Issaka Sagara
- Malaria Research and Training Center, University of Sciences, Techniques, and Technology, Bamako, Mali
| | - Kazutoyo Miura
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Patrick E Duffy
- Pathogenesis and Immunity Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, USA
| | - Niraj H Tolia
- Host-Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, USA.
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10
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Guissou E, Da DF, Hien DFDS, Yameogo KB, Yerbanga SR, Ouédraogo GA, Dabiré KR, Lefèvre T, Cohuet A. Intervention reducing malaria parasite load in vector mosquitoes: No impact on Plasmodium falciparum extrinsic incubation period and the survival of Anopheles gambiae. PLoS Pathog 2023; 19:e1011084. [PMID: 37195964 PMCID: PMC10191285 DOI: 10.1371/journal.ppat.1011084] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2022] [Accepted: 04/18/2023] [Indexed: 05/19/2023] Open
Abstract
In the fight against malaria, transmission blocking interventions (TBIs) such as transmission blocking vaccines or drugs, are promising approaches to complement conventional tools. They aim to prevent the infection of vectors and thereby reduce the subsequent exposure of a human population to infectious mosquitoes. The effectiveness of these approaches has been shown to depend on the initial intensity of infection in mosquitoes, often measured as the mean number of oocysts resulting from an infectious blood meal in absence of intervention. In mosquitoes exposed to a high intensity of infection, current TBI candidates are expected to be ineffective at completely blocking infection but will decrease parasite load and therefore, potentially also affect key parameters of vector transmission. The present study investigated the consequences of changes in oocyst intensity on subsequent parasite development and mosquito survival. To address this, we experimentally produced different intensities of infection for Anopheles gambiae females from Burkina Faso by diluting gametocytes from three natural Plasmodium falciparum local isolates and used a newly developed non-destructive method based on the exploitation of mosquito sugar feeding to track parasite and mosquito life history traits throughout sporogonic development. Our results indicate the extrinsic incubation period (EIP) of P. falciparum and mosquito survival did not vary with parasite density but differed significantly between parasite isolates with estimated EIP50 of 16 (95% CI: 15-18), 14 (95% CI: 12-16) and 12 (95% CI: 12-13) days and median longevity of 25 (95% CI: 22-29), 15 (95% CI: 13-15) and 18 (95% CI: 17-19) days for the three isolates respectively. Our results here do not identify unintended consequences of the decrease of parasite loads in mosquitoes on the parasite incubation period or on mosquito survival, two key parameters of vectorial capacity, and hence support the use of transmission blocking strategies to control malaria.
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Affiliation(s)
- Edwige Guissou
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
- MIVEGEC, Montpellier University, IRD, CNRS, Montpellier, France
- Université Nazi Boni, Bobo-Dioulasso, Burkina Faso
- Ecole Normale Supérieure, Koudougou, Burkina Faso
| | - Dari Frédéric Da
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | | | | | | | | | | | - Thierry Lefèvre
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
- MIVEGEC, Montpellier University, IRD, CNRS, Montpellier, France
| | - Anna Cohuet
- MIVEGEC, Montpellier University, IRD, CNRS, Montpellier, France
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11
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Tang WK, Coelho CH, Miura K, Nguemwo Tentokam BC, Salinas ND, Narum DL, Healy SA, Sagara I, Long CA, Duffy PE, Tolia NH. A human antibody epitope map of Pfs230D1 derived from analysis of individuals vaccinated with a malaria transmission-blocking vaccine. Immunity 2023; 56:433-443.e5. [PMID: 36792576 PMCID: PMC9989938 DOI: 10.1016/j.immuni.2023.01.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 12/07/2022] [Accepted: 01/13/2023] [Indexed: 02/16/2023]
Abstract
Pfs230 domain 1 (Pfs230D1) is an advanced malaria transmission-blocking vaccine antigen demonstrating high functional activity in clinical trials. However, the structural and functional correlates of transmission-blocking activity are not defined. Here, we characterized a panel of human monoclonal antibodies (hmAbs) elicited in vaccinees immunized with Pfs230D1. These hmAbs exhibited diverse transmission-reducing activity, yet all bound to Pfs230D1 with nanomolar affinity. We compiled epitope-binning data for seventeen hmAbs and structures of nine hmAbs complexes to construct a high-resolution epitope map and revealed that potent transmission-reducing hmAbs bound to one face of Pfs230D1, while non-potent hmAbs bound to the opposing side. The structure of Pfs230D1D2 revealed that non-potent transmission-reducing epitopes were occluded by the second domain. The hmAb epitope map delineated binary hmAb combinations that synergized for extremely high-potency, transmission-reducing activity. This work provides a high-resolution guide for structure-based design of enhanced immunogens and informs diagnostics that measure the transmission-reducing response.
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Affiliation(s)
- Wai Kwan Tang
- Host-Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Camila H Coelho
- Pathogenesis and Immunity Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Kazutoyo Miura
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Bergeline C Nguemwo Tentokam
- Pathogenesis and Immunity Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Nichole D Salinas
- Host-Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - David L Narum
- Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Sara A Healy
- Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Issaka Sagara
- Malaria Research and Training Center, University of Sciences, Techniques, and Technology, Bamako, Mali
| | - Carole A Long
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Patrick E Duffy
- Pathogenesis and Immunity Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA; Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA.
| | - Niraj H Tolia
- Host-Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA.
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12
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A Novel Ex Vivo Drug Assay for Assessing the Transmission-Blocking Activity of Compounds on Field-Isolated Plasmodium falciparum Gametocytes. Antimicrob Agents Chemother 2022; 66:e0100122. [PMID: 36321830 PMCID: PMC9764978 DOI: 10.1128/aac.01001-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The discovery and development of transmission-blocking therapies challenge malaria elimination and necessitate standard and reproducible bioassays to measure the blocking properties of antimalarial drugs and candidate compounds. Most of the current bioassays evaluating the transmission-blocking activity of compounds rely on laboratory-adapted Plasmodium strains. Transmission-blocking data from clinical gametocyte isolates could help select novel transmission-blocking candidates for further development. Using freshly collected Plasmodium falciparum gametocytes from asymptomatic individuals, we first optimized ex vivo culture conditions to improve gametocyte viability and infectiousness by testing several culture parameters. We next pre-exposed ex vivo field-isolated gametocytes to chloroquine, dihydroartemisinin, primaquine, KDU691, GNF179, and oryzalin for 48 h prior to direct membrane feeding. We measured the activity of the drug on the ability of gametocytes to resume the sexual life cycle in Anopheles after drug exposure. Using 57 blood samples collected from Malian volunteers aged 6 to 15 years, we demonstrate that the infectivity of freshly collected field gametocytes can be preserved and improved ex vivo in a culture medium supplemented with 10% horse serum at 4% hematocrit for 48 h. Moreover, our optimized drug assay displays the weak transmission-blocking activity of chloroquine and dihydroartemisinin, while primaquine and oryzalin exhibited a transmission-blocking activity of ~50% at 1 μM. KDU691 and GNF179 both interrupted Plasmodium transmission at 1 μM and 5 nM, respectively. This new approach, if implemented, has the potential to accelerate the screening of compounds with transmission-blocking activity.
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13
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Ko KT, Lennartz F, Mekhaiel D, Guloglu B, Marini A, Deuker DJ, Long CA, Jore MM, Miura K, Biswas S, Higgins MK. Structure of the malaria vaccine candidate Pfs48/45 and its recognition by transmission blocking antibodies. Nat Commun 2022; 13:5603. [PMID: 36153317 PMCID: PMC9509318 DOI: 10.1038/s41467-022-33379-6] [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: 05/24/2022] [Accepted: 09/14/2022] [Indexed: 12/05/2022] Open
Abstract
An effective malaria vaccine remains a global health priority and vaccine immunogens which prevent transmission of the parasite will have important roles in multi-component vaccines. One of the most promising candidates for inclusion in a transmission-blocking malaria vaccine is the gamete surface protein Pfs48/45, which is essential for development of the parasite in the mosquito midgut. Indeed, antibodies which bind Pfs48/45 can prevent transmission if ingested with the parasite as part of the mosquito bloodmeal. Here we present the structure of full-length Pfs48/45, showing its three domains to form a dynamic, planar, triangular arrangement. We reveal where transmission-blocking and non-blocking antibodies bind on Pfs48/45. Finally, we demonstrate that antibodies which bind across this molecule can be transmission-blocking. These studies will guide the development of future Pfs48/45-based vaccine immunogens.
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Affiliation(s)
- Kuang-Ting Ko
- Department of Biochemistry, South Parks Road, University of Oxford, Oxford, OX1 3QU, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, South Parks Rd, Oxford, OX1 3QU, UK
| | - Frank Lennartz
- Department of Biochemistry, South Parks Road, University of Oxford, Oxford, OX1 3QU, UK
| | - David Mekhaiel
- Jenner Institute, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford, OX3 7DQ, UK
| | - Bora Guloglu
- Department of Biochemistry, South Parks Road, University of Oxford, Oxford, OX1 3QU, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, South Parks Rd, Oxford, OX1 3QU, UK
| | - Arianna Marini
- Jenner Institute, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford, OX3 7DQ, UK
| | - Danielle J Deuker
- Jenner Institute, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford, OX3 7DQ, UK
| | - Carole A Long
- Malaria Immunology Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, NIH, Rockville, MD, USA
| | - Matthijs M Jore
- Department of Medical Microbiology, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Kazutoyo Miura
- Malaria Immunology Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, NIH, Rockville, MD, USA
| | - Sumi Biswas
- Jenner Institute, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford, OX3 7DQ, UK.
| | - Matthew K Higgins
- Department of Biochemistry, South Parks Road, University of Oxford, Oxford, OX1 3QU, UK.
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, South Parks Rd, Oxford, OX1 3QU, UK.
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14
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McLeod B, Mabrouk MT, Miura K, Ravichandran R, Kephart S, Hailemariam S, Pham TP, Semesi A, Kucharska I, Kundu P, Huang WC, Johnson M, Blackstone A, Pettie D, Murphy M, Kraft JC, Leaf EM, Jiao Y, van de Vegte-Bolmer M, van Gemert GJ, Ramjith J, King CR, MacGill RS, Wu Y, Lee KK, Jore MM, King NP, Lovell JF, Julien JP. Vaccination with a structure-based stabilized version of malarial antigen Pfs48/45 elicits ultra-potent transmission-blocking antibody responses. Immunity 2022; 55:1680-1692.e8. [PMID: 35977542 PMCID: PMC9487866 DOI: 10.1016/j.immuni.2022.07.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 07/07/2022] [Accepted: 07/18/2022] [Indexed: 02/08/2023]
Abstract
Malaria transmission-blocking vaccines (TBVs) aim to elicit human antibodies that inhibit sporogonic development of Plasmodium falciparum in mosquitoes, thereby preventing onward transmission. Pfs48/45 is a leading clinical TBV candidate antigen and is recognized by the most potent transmission-blocking monoclonal antibody (mAb) yet described; still, clinical development of Pfs48/45 antigens has been hindered, largely by its poor biochemical characteristics. Here, we used structure-based computational approaches to design Pfs48/45 antigens stabilized in the conformation recognized by the most potently inhibitory mAb, achieving >25°C higher thermostability compared with the wild-type protein. Antibodies elicited in mice immunized with these engineered antigens displayed on liposome-based or protein nanoparticle-based vaccine platforms exhibited 1-2 orders of magnitude superior transmission-reducing activity, compared with immunogens bearing the wild-type antigen, driven by improved antibody quality. Our data provide the founding principles for using molecular stabilization solely from antibody structure-function information to drive improved immune responses against a parasitic vaccine target.
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Affiliation(s)
- Brandon McLeod
- Program in Molecular Medicine, The Hospital for Sick Children Research Institute, 686 Bay Street, Toronto, ON M5G 0A4, Canada; Department of Biochemistry, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada
| | - Moustafa T Mabrouk
- Department of Biomedical Engineering, University at Buffalo, State University of New York, Buffalo, NY 14260, USA
| | - Kazutoyo Miura
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 12735 Twinbrook Parkway, Rockville, MD 20852, USA
| | - Rashmi Ravichandran
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA; Institute for Protein Design, University of Washington, Seattle, WA 98195, USA
| | - Sally Kephart
- Department of Medicinal Chemistry, University of Washington, Seattle, WA 98195, USA
| | - Sophia Hailemariam
- Program in Molecular Medicine, The Hospital for Sick Children Research Institute, 686 Bay Street, Toronto, ON M5G 0A4, Canada; Department of Biochemistry, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada
| | - Thao P Pham
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 12735 Twinbrook Parkway, Rockville, MD 20852, USA
| | - Anthony Semesi
- Program in Molecular Medicine, The Hospital for Sick Children Research Institute, 686 Bay Street, Toronto, ON M5G 0A4, Canada
| | - Iga Kucharska
- Program in Molecular Medicine, The Hospital for Sick Children Research Institute, 686 Bay Street, Toronto, ON M5G 0A4, Canada
| | - Prasun Kundu
- Program in Molecular Medicine, The Hospital for Sick Children Research Institute, 686 Bay Street, Toronto, ON M5G 0A4, Canada
| | - Wei-Chiao Huang
- Department of Biomedical Engineering, University at Buffalo, State University of New York, Buffalo, NY 14260, USA
| | - Max Johnson
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA; Institute for Protein Design, University of Washington, Seattle, WA 98195, USA
| | - Alyssa Blackstone
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA; Institute for Protein Design, University of Washington, Seattle, WA 98195, USA
| | - Deleah Pettie
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA; Institute for Protein Design, University of Washington, Seattle, WA 98195, USA
| | - Michael Murphy
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA; Institute for Protein Design, University of Washington, Seattle, WA 98195, USA
| | - John C Kraft
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA; Institute for Protein Design, University of Washington, Seattle, WA 98195, USA
| | - Elizabeth M Leaf
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA; Institute for Protein Design, University of Washington, Seattle, WA 98195, USA
| | - Yang Jiao
- Department of Biomedical Engineering, University at Buffalo, State University of New York, Buffalo, NY 14260, USA
| | | | - Geert-Jan van Gemert
- Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Jordache Ramjith
- Radboud Institute for Health Sciences, Department for Health Evidence, Biostatistics Section, Radboud University Medical Center, Nijmegen, the Netherlands
| | - C Richter King
- PATH's Malaria Vaccine Initiative, 455 Massachusetts Avenue NW Suite 1000, Washington, DC 20001, USA
| | - Randall S MacGill
- PATH's Malaria Vaccine Initiative, 455 Massachusetts Avenue NW Suite 1000, Washington, DC 20001, USA
| | - Yimin Wu
- PATH's Malaria Vaccine Initiative, 455 Massachusetts Avenue NW Suite 1000, Washington, DC 20001, USA
| | - Kelly K Lee
- Department of Medicinal Chemistry, University of Washington, Seattle, WA 98195, USA
| | - Matthijs M Jore
- Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Neil P King
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA; Institute for Protein Design, University of Washington, Seattle, WA 98195, USA
| | - Jonathan F Lovell
- Department of Biomedical Engineering, University at Buffalo, State University of New York, Buffalo, NY 14260, USA
| | - Jean-Philippe Julien
- Program in Molecular Medicine, The Hospital for Sick Children Research Institute, 686 Bay Street, Toronto, ON M5G 0A4, Canada; Department of Biochemistry, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada; Department of Immunology, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada.
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15
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Hasyim AA, Iyori M, Mizuno T, Abe YI, Yamagoshi I, Yusuf Y, Syafira I, Sakamoto A, Yamamoto Y, Mizukami H, Shida H, Yoshida S. Adeno-associated virus-based malaria booster vaccine following attenuated replication-competent vaccinia virus LC16m8Δ priming. Parasitol Int 2022; 92:102652. [PMID: 36007703 DOI: 10.1016/j.parint.2022.102652] [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: 07/28/2022] [Revised: 08/16/2022] [Accepted: 08/18/2022] [Indexed: 11/16/2022]
Abstract
We previously demonstrated that boosting with adeno-associated virus (AAV) type 1 (AAV1) can induce highly effective and long-lasting protective immune responses against malaria parasites when combined with replication-deficient adenovirus priming in a rodent model. In the present study, we compared the efficacy of two different AAV serotypes, AAV1 and AAV5, as malaria booster vaccines following priming with the attenuated replication-competent vaccinia virus strain LC16m8Δ (m8Δ), which harbors the fusion gene encoding both the pre-erythrocytic stage protein, Plasmodium falciparum circumsporozoite (PfCSP) and the sexual stage protein (Pfs25) in a two-dose heterologous prime-boost immunization regimen. Both regimens, m8Δ/AAV1 and m8Δ/AAV5, induced robust anti-PfCSP and anti-Pfs25 antibodies. To evaluate the protective efficacy, the mice were challenged with sporozoites twice after immunization. At the first sporozoite challenge, m8Δ/AAV5 achieved 100% sterile protection whereas m8Δ/AAV1 achieved 70% protection. However, at the second challenge, 100% of the surviving mice from the first challenge were protected in the m8Δ/AAV1 group whereas only 55.6% of those in the m8Δ/AAV5 group were protected. Regarding the transmission-blocking efficacy, we found that both immunization regimens induced high levels of transmission-reducing activity (>99%) and transmission-blocking activity (>95%). Our data indicate that the AAV5-based multistage malaria vaccine is as effective as the AAV1-based vaccine when administered following an m8Δ-based vaccine. These results suggest that AAV5 could be a viable alternate vaccine vector as a malaria booster vaccine.
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Affiliation(s)
- Ammar A Hasyim
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa, Ishikawa 920-1192, Japan
| | - Mitsuhiro Iyori
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa, Ishikawa 920-1192, Japan
| | - Tetsushi Mizuno
- Department of Global Infectious Diseases, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Ishikawa 920-0934, Japan
| | - Yu-Ichi Abe
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa, Ishikawa 920-1192, Japan
| | - Iroha Yamagoshi
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa, Ishikawa 920-1192, Japan
| | - Yenni Yusuf
- Department of Parasitology, Faculty of Medicine, Hasanuddin University, Makassar, Sulawesi Selatan 90245, Indonesia
| | - Intan Syafira
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa, Ishikawa 920-1192, Japan
| | - Akihiko Sakamoto
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa, Ishikawa 920-1192, Japan
| | - Yutaro Yamamoto
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa, Ishikawa 920-1192, Japan
| | - Hiroaki Mizukami
- Division of Gene Therapy, Jichi Medical University, Shimotsuke, Tochigi 329-0498, Japan
| | - Hisatoshi Shida
- Institute for Genetic Medicine, Hokkaido University, Sapporo, Hokkaido 060-0815, Japan
| | - Shigeto Yoshida
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa, Ishikawa 920-1192, Japan.
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16
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Mulamba C, Williams C, Kreppel K, Ouedraogo JB, Olotu AI. Evaluation of the Pfs25-IMX313/Matrix-M malaria transmission-blocking candidate vaccine in endemic settings. Malar J 2022; 21:159. [PMID: 35655174 PMCID: PMC9161629 DOI: 10.1186/s12936-022-04173-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 05/02/2022] [Indexed: 11/10/2022] Open
Abstract
Malaria control relies heavily on the use of anti-malarial drugs and insecticides against malaria parasites and mosquito vectors. Drug and insecticide resistance threatens the effectiveness of conventional malarial interventions; alternative control approaches are, therefore, needed. The development of malaria transmission-blocking vaccines that target the sexual stages in humans or mosquito vectors is among new approaches being pursued. Here, the immunological mechanisms underlying malaria transmission blocking, status of Pfs25-based vaccines are viewed, as well as approaches and capacity for first in-human evaluation of a transmission-blocking candidate vaccine Pfs25-IMX313/Matrix-M administered to semi-immune healthy individuals in endemic settings. It is concluded that institutions in low and middle income settings should be supported to conduct first-in human vaccine trials in order to stimulate innovative research and reduce the overdependence on developed countries for research and local interventions against many diseases of public health importance.
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Affiliation(s)
- Charles Mulamba
- Interventions & Clinical Trials Department, Ifakara Health Institute, P.O. Box 74, Bagamoyo, Tanzania.,Nelson Mandela African Institution of Science and Technology, Tengeru, P. O. Box 447, Arusha, Tanzania
| | - Chris Williams
- The Jenner Institute, University of Oxford, Roosevelt Drive, Headington, Oxford, OX3 7DQ, UK
| | - Katharina Kreppel
- Nelson Mandela African Institution of Science and Technology, Tengeru, P. O. Box 447, Arusha, Tanzania
| | | | - Ally I Olotu
- Interventions & Clinical Trials Department, Ifakara Health Institute, P.O. Box 74, Bagamoyo, Tanzania.
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17
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Elucidating functional epitopes within the N-terminal region of malaria transmission blocking vaccine antigen Pfs230. NPJ Vaccines 2022; 7:4. [PMID: 35027567 PMCID: PMC8758780 DOI: 10.1038/s41541-021-00423-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 11/30/2021] [Indexed: 11/24/2022] Open
Abstract
Pfs230 is a leading malaria transmission blocking vaccine (TBV) candidate. Comprising 3135 amino acids (aa), the large size of Pfs230 necessitates the use of sub-fragments as vaccine immunogens. Therefore, determination of which regions induce functional antibody responses is essential. We previously reported that of 27 sub-fragments spanning the entire molecule, only five induced functional antibodies. A “functional” antibody is defined herein as one that inhibits Plasmodium falciparum parasite development in mosquitoes in a standard membrane-feeding assay (SMFA). These five sub-fragments were found within the aa 443–1274 range, and all contained aa 543–730. Here, we further pinpoint the location of epitopes within Pfs230 that are recognized by functional antibodies using antibody depletion and enrichment techniques. Functional epitopes were not found within the aa 918–1274 region. Within aa 443–917, further analysis showed the existence of functional epitopes not only within the aa 543–730 region but also outside of it. Affinity-purified antibodies using a synthetic peptide matching aa 543–588 showed activity in the SMFA. Immunization with a synthetic peptide comprising this segment, formulated either as a carrier-protein conjugate vaccine or with a liposomal vaccine adjuvant system, induced antibodies in mice that were functional in the SMFA. These findings provide key insights for Pfs230-based vaccine design and establish the feasibility for the use of synthetic peptide antigens for a malaria TBV.
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18
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Arévalo-Herrera M, Miura K, Solano E, Ramírez JS, Long CA, Corradin G, Herrera S. Immunogenicity of full-length P. vivax rPvs48/45 protein formulations in BALB/c mice. Vaccine 2022; 40:133-140. [PMID: 34802791 PMCID: PMC9109962 DOI: 10.1016/j.vaccine.2021.11.036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 10/12/2021] [Accepted: 11/11/2021] [Indexed: 01/05/2023]
Abstract
BACKGROUND Pvs48/45 is a Plasmodium vivax gametocyte surface protein involved in the parasite fertilization process. Previous studies showed that Pvs48/45 proteins expressed in Escherichia coli (E. coli) and Chinese hamster ovary (CHO) cells were highly immunoreactive with sera from malaria-endemic areas and highly immunogenic in animal models. Here the immunogenicity in mice of three different vaccine formulations was compared. METHODS Recombinant (r) Pvs48/45 proteins were expressed in E. coli and CHO, purified, formulated in Alhydrogel, GLA-SE and Montanide ISA-51 adjuvants and used to immunize BALB/c mice. Animals were immunized on days 0, 20 and 40, and serum samples were collected for serological analyses of specific antibody responses using ELISA and immunofluorescence (IFAT). Additionally, ex-vivo transmission-reducing activity (TRA) of sera on P. vivax gametocyte-infected human blood fed to Anopheles albimanus in direct membrane feeding assays (DMFA) was evaluated. RESULTS Most immunized animals seroconverted after the first immunization, and some developed antibody peaks of 106 with all adjuvants. However, the three adjuvant formulations induced different antibody responses and TRA efficacy. While GLA-SE formulations of both proteins induced similar antibody profiles, Montanide ISA-51 formulations resulted in higher and longer-lasting antibody titers with CHO-rPvs48/45 than with the E. coli formulation. Although the CHO protein formulated in Alhydrogel generated a high initial antibody peak, antibody responses to both proteins rapidly waned. Likewise, anti-Pvs48/45 antibodies displayed differential recognition of the parasite proteins in IFAT and ex vivo blockade of parasite transmission to mosquitoes. The CHO-rPvs48/45 formulated in Montanide ISA-51 induced the most effective ex vivo parasite blockage. CONCLUSIONS Three out of six vaccine formulations elicited antibodies with ex vivo TRA. The CHO-rPvs48/45 Montanide ISA-51 formulation induced the most stable antibody response, recognizing the native protein and the most robust ex vivo TRA. These results encourage further testing of the vaccine potential of this protein.
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Affiliation(s)
- Myriam Arévalo-Herrera
- Malaria Vaccine and Drug Development Center, Cali, Colombia.,Caucaseco Scientific Research Center, Cali, Colombia.,Corresponding author: Myriam Arevalo-Herrera, PhD, , Phone: (+57 2) 521 6232, Fax: (+57 2) 521 6228, Malaria Vaccine and Drug Development Center, Carrera 37 2 Bis # 5E-08. Cali, Colombia
| | - Kazutoyo Miura
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | | | | | - Carole A. Long
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | | | - Sócrates Herrera
- Malaria Vaccine and Drug Development Center, Cali, Colombia.,Caucaseco Scientific Research Center, Cali, Colombia
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19
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Zaric M, Marini A, Nielsen CM, Gupta G, Mekhaiel D, Pham TP, Elias SC, Taylor IJ, de Graaf H, Payne RO, Li Y, Silk SE, Williams C, Hill AVS, Long CA, Miura K, Biswas S. Poor CD4 + T Cell Immunogenicity Limits Humoral Immunity to P. falciparum Transmission-Blocking Candidate Pfs25 in Humans. Front Immunol 2021; 12:732667. [PMID: 34659219 PMCID: PMC8515144 DOI: 10.3389/fimmu.2021.732667] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 09/07/2021] [Indexed: 11/13/2022] Open
Abstract
Plasmodium falciparum transmission-blocking vaccines (TBVs) targeting the Pfs25 antigen have shown promise in mice but the same efficacy has never been achieved in humans. We have previously published pre-clinical data related to a TBV candidate Pfs25-IMX313 encoded in viral vectors which was very promising and hence progressed to human clinical trials. The results from the clinical trial of this vaccine were very modest. Here we unravel why, contrary to mice, this vaccine has failed to induce robust antibody (Ab) titres in humans to elicit transmission-blocking activity. We examined Pfs25-specific B cell and T follicular helper (Tfh) cell responses in mice and humans after vaccination with Pfs25-IMX313 encoded by replication-deficient chimpanzee adenovirus serotype 63 (ChAd63) and the attenuated orthopoxvirus modified vaccinia virus Ankara (MVA) delivered in the heterologous prime-boost regimen via intramuscular route. We found that after vaccination, the Pfs25-IMX313 was immunologically suboptimal in humans compared to mice in terms of serum Ab production and antigen-specific B, CD4+ and Tfh cell responses. We identified that the key determinant for the poor anti-Pfs25 Ab formation in humans was the lack of CD4+ T cell recognition of Pfs25-IMX313 derived peptide epitopes. This is supported by correlations established between the ratio of proliferated antigen-specific CD4+/Tfh-like T cells, CXCL13 sera levels, and the corresponding numbers of circulating Pfs25-specific memory B cells, that consequently reflected on antigen-specific IgG sera levels. These correlations can inform the design of next-generation Pfs25-based vaccines for robust and durable blocking of malaria transmission.
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Affiliation(s)
- Marija Zaric
- Nuffield Department of Medicine, The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Arianna Marini
- Nuffield Department of Medicine, The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Carolyn M Nielsen
- Nuffield Department of Medicine, The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Gaurav Gupta
- Nuffield Department of Medicine, The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - David Mekhaiel
- Nuffield Department of Medicine, The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Thao P Pham
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Disease, National Institutes of Health, Rockville, MD, United States
| | - Sean C Elias
- Nuffield Department of Medicine, The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Iona J Taylor
- Nuffield Department of Medicine, The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Hans de Graaf
- NIHR Clinical Research Facility, University Hospital Southampton NHS Foundation Trust and Faculty of Medicine, University of Southampton, Southampton, United Kingdom
| | - Ruth O Payne
- Nuffield Department of Medicine, The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Yuanyuan Li
- Nuffield Department of Medicine, The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Sarah E Silk
- Nuffield Department of Medicine, The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Chris Williams
- Nuffield Department of Medicine, The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Adrian V S Hill
- Nuffield Department of Medicine, The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Carole A Long
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Disease, National Institutes of Health, Rockville, MD, United States
| | - Kazutoyo Miura
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Disease, National Institutes of Health, Rockville, MD, United States
| | - Sumi Biswas
- Nuffield Department of Medicine, The Jenner Institute, University of Oxford, Oxford, United Kingdom
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20
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Arévalo-Herrera M, Miura K, Cespedes N, Echeverry C, Solano E, Castellanos A, Ramirez JS, Miranda A, Kajava AV, Long C, Corradin G, Herrera S. Immunoreactivity of Sera From Low to Moderate Malaria-Endemic Areas Against Plasmodium vivax r Pvs48/45 Proteins Produced in Escherichia coli and Chinese Hamster Ovary Systems. Front Immunol 2021; 12:634738. [PMID: 34248932 PMCID: PMC8264144 DOI: 10.3389/fimmu.2021.634738] [Citation(s) in RCA: 6] [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: 11/28/2020] [Accepted: 05/25/2021] [Indexed: 11/13/2022] Open
Abstract
P48/45 is a conserved gametocyte antigen involved in Plasmodium parasite fertilization. A recombinant Plasmodium vivax P48/45 (Pvs48/45) protein expressed in Escherichia coli (E. coli) was highly antigenic and immunogenic in experimental animals and elicited specific transmission-blocking (TB) antibodies in a previous pilot study. Here, a similar Pvs48/45 gene was expressed in Chinese Hamster Ovary (CHO) cells and we compared its immunoreactivity with the E. coli product. Specific antibody titers were determined using plasma from Colombian individuals (n=227) living in endemic areas where both P. vivax and P. falciparum are prevalent and from Guatemala (n=54) where P. vivax is highly prevalent. In Colombia, plasma seroprevalence to CHO-rPvs48/45 protein was 46.3%, while for E. coli-rPvs48/45 protein was 36.1% (p<0.001). In Guatemala, the sero prevalence was 24.1% and 14.8% (p<0.001), respectively. Reactivity index (RI) against both proteins showed an age-dependent increase. IgG2 was the predominant subclass and the antibody avidity index evaluated by ELISA ranged between 4-6 mol/L. Ex vivo P. vivax mosquito direct membrane feeding assays (DMFA) performed in presence of study plasmas, displayed significant parasite transmission-blocking (TB), however, there was no direct correlation between antibody titers and oocysts transmission reduction activity (%TRA). Nevertheless, DMFA with CHO rPvs48/45 affinity purified IgG showed a dose response; 90.2% TRA at 100 μg/mL and 71.8% inhibition at 10 μg/mL. In conclusion, the CHO-rPvs48/45 protein was more immunoreactive in most of the malaria endemic places studied, and CHO-rPvs48/45 specific IgG showed functional activity, supporting further testing of the protein vaccine potential.
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Affiliation(s)
- Myriam Arévalo-Herrera
- Immunology Department, Malaria Vaccine and Drug Development Center, Cali, Colombia
- Immunology Department, Caucaseco Scientific Research Center, Cali, Colombia
| | - Kazutoyo Miura
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, United States
| | - Nora Cespedes
- Immunology Department, Malaria Vaccine and Drug Development Center, Cali, Colombia
| | - Carlos Echeverry
- Immunology Department, Malaria Vaccine and Drug Development Center, Cali, Colombia
| | - Eduardo Solano
- Immunology Department, Caucaseco Scientific Research Center, Cali, Colombia
| | - Angélica Castellanos
- Immunology Department, Malaria Vaccine and Drug Development Center, Cali, Colombia
| | | | - Adolfo Miranda
- Parasitology Department, Centro Nacional de Epidemiología (CNE), Guatemala City, Guatemala
| | - Andrey V. Kajava
- Centre de Recherche en Biologie Cellulaire de Montpellier, Université Montpellier, Montpellier, France
| | - Carole Long
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, United States
| | | | - Sócrates Herrera
- Immunology Department, Malaria Vaccine and Drug Development Center, Cali, Colombia
- Immunology Department, Caucaseco Scientific Research Center, Cali, Colombia
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21
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Tripathi AK, Oakley MS, Verma N, Mlambo G, Zheng H, Meredith SM, Essuman E, Puri A, Skelton RA, Takeda K, Majam V, Quakyi IA, Locke E, Morin M, Miura K, Long CA, Kumar S. Plasmodium falciparum Pf77 and male development gene 1 as vaccine antigens that induce potent transmission-reducing antibodies. Sci Transl Med 2021; 13:eabg2112. [PMID: 34108248 PMCID: PMC11018285 DOI: 10.1126/scitranslmed.abg2112] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 04/22/2021] [Indexed: 12/14/2022]
Abstract
Malaria vaccines that disrupt the Plasmodium life cycle in mosquitoes and reduce parasite transmission in endemic areas are termed transmission-blocking vaccines (TBVs). Despite decades of research, there are only a few Plasmodium falciparum antigens that indisputably and reproducibly demonstrate transmission-blocking immunity. So far, only two TBV candidates have advanced to phase 1/2 clinical testing with limited success. By applying an unbiased transcriptomics-based approach, we have identified Pf77 and male development gene 1 (PfMDV-1) as two P. falciparum TBV antigens that, upon immunization, induced antibodies that caused reductions in oocyst counts in Anopheles mosquito midguts in a standard membrane feeding assay. In-depth studies were performed to characterize the genetic diversity of, stage-specific expression by, and natural immunity to these two molecules to evaluate their suitability as TBV candidates. Pf77 and PfMDV-1 display limited antigenic polymorphism, are pan-developmentally expressed within the parasite, and induce naturally occurring antibodies in Ghanaian adults, which raises the prospect of natural boosting of vaccine-induced immune response in endemic regions. Together, these biological properties suggest that Pf77 and PfMDV-1 may warrant further investigation as TBV candidates.
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Affiliation(s)
- Abhai K Tripathi
- Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Miranda S Oakley
- Laboratory of Emerging Pathogens, Division of Emerging and Transfusion Transmitted Diseases, Office of Blood Research and Review, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20993, USA
| | - Nitin Verma
- Laboratory of Emerging Pathogens, Division of Emerging and Transfusion Transmitted Diseases, Office of Blood Research and Review, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20993, USA
| | - Godfree Mlambo
- Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Hong Zheng
- Laboratory of Emerging Pathogens, Division of Emerging and Transfusion Transmitted Diseases, Office of Blood Research and Review, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20993, USA
| | - Scott M Meredith
- Laboratory of Emerging Pathogens, Division of Emerging and Transfusion Transmitted Diseases, Office of Blood Research and Review, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20993, USA
| | - Edward Essuman
- Laboratory of Emerging Pathogens, Division of Emerging and Transfusion Transmitted Diseases, Office of Blood Research and Review, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20993, USA
| | - Ankit Puri
- Laboratory of Emerging Pathogens, Division of Emerging and Transfusion Transmitted Diseases, Office of Blood Research and Review, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20993, USA
| | - Richard A Skelton
- Laboratory of Emerging Pathogens, Division of Emerging and Transfusion Transmitted Diseases, Office of Blood Research and Review, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20993, USA
| | - Kazuyo Takeda
- Division of Bacterial, Parasitic, and Allergenic Products, Office of Vaccines Research and Review, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20993, USA
| | - Victoria Majam
- Laboratory of Emerging Pathogens, Division of Emerging and Transfusion Transmitted Diseases, Office of Blood Research and Review, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20993, USA
| | | | - Emily Locke
- PATH-Malaria Vaccine Initiative, Washington, DC 20001, USA
| | | | - Kazutoyo Miura
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Carole A Long
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Sanjai Kumar
- Laboratory of Emerging Pathogens, Division of Emerging and Transfusion Transmitted Diseases, Office of Blood Research and Review, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20993, USA.
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22
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Yang F, Liu F, Yu X, Zheng W, Wu Y, Qiu Y, Jin Y, Cui L, Cao Y. Evaluation of two sexual-stage antigens as bivalent transmission-blocking vaccines in rodent malaria. Parasit Vectors 2021; 14:241. [PMID: 33962671 PMCID: PMC8103607 DOI: 10.1186/s13071-021-04743-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 04/23/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Transmission-blocking vaccine (TBV) is a promising strategy for malaria elimination. It is hypothesized that mixing or fusing two antigens targeting different stages of sexual development may provide higher transmission-blocking activity than these antigens used individually. METHODS A chimeric protein composed of fragments of Pbg37 and PSOP25 was designed and expressed the recombinant protein in Escherichia coli Rosetta-gami B (DE3). After immunizing mice with individual recombinant proteins Pbg37 and PSOP25, mixed proteins (Pbg37+PSOP25), or the fusion protein (Pbg37-PSOP25), the antibody titers of individual sera were analyzed by ELISA. IFA and Western blot were performed to test the reactivity of the antisera with the native proteins in the parasite. The transmission-blocking activity of the different immunization schemes was assessed using in vitro and in vivo assays. RESULTS When Pbg37 and PSOP25 were co-administered in a mixture or as a fusion protein, they elicited similar antibody responses in mice as single antigens without causing immunological interference with each other. Antibodies against the mixed or fused antigens recognized the target proteins in the gametocyte, gamete, zygote, and ookinete stages. The mixed proteins or the fusion protein induced antibodies with significantly stronger transmission-reducing activities in vitro and in vivo than individual antigens. CONCLUSIONS There was no immunological interference between Pbg37 and PSOP25. The bivalent vaccines, which expand the portion of the sexual development during which the transmission-blocking antibodies act, produced significantly stronger transmission-reducing activities than single antigens. Altogether, these data provide the theoretical basis for the development of combination TBVs targeting different sexual stages.
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Affiliation(s)
- Fan Yang
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang, 110122, Liaoning, China
| | - Fei Liu
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang, 110122, Liaoning, China
| | - Xinxin Yu
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang, 110122, Liaoning, China
| | - Wenqi Zheng
- Department of Laboratory Medicine, The Affiliated Hospital of Inner Mongolia Medical University, Hohhot, China
| | - Yudi Wu
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang, 110122, Liaoning, China
| | - Yue Qiu
- The First Affiliated Hospital of China Medical University, 155 Nanjing North Street, Heping District, Shenyang, 110001, Liaoning, China
| | - Ying Jin
- Liaoning Research Institute of Family Planning, Shenyang, 110031, China
| | - Liwang Cui
- Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL, 33612, USA
| | - Yaming Cao
- Department of Immunology, College of Basic Medical Sciences, China Medical University, Shenyang, 110122, Liaoning, China.
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23
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Healy SA, Anderson C, Swihart BJ, Mwakingwe A, Gabriel EE, Decederfelt H, Hobbs CV, Rausch KM, Zhu D, Muratova O, Herrera R, Scaria PV, MacDonald NJ, Lambert LE, Zaidi I, Coelho CH, Renn JP, Wu Y, Narum DL, Duffy PE. Pfs230 yields higher malaria transmission-blocking vaccine activity than Pfs25 in humans but not mice. J Clin Invest 2021; 131:146221. [PMID: 33561016 PMCID: PMC8011888 DOI: 10.1172/jci146221] [Citation(s) in RCA: 56] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 02/03/2021] [Indexed: 12/19/2022] Open
Abstract
BACKGROUNDVaccines that block human-to-mosquito Plasmodium transmission are needed for malaria eradication, and clinical trials have targeted zygote antigen Pfs25 for decades. We reported that a Pfs25 protein-protein conjugate vaccine formulated in alum adjuvant induced serum functional activity in both US and Malian adults. However, antibody levels declined rapidly, and transmission-reducing activity required 4 vaccine doses. Functional immunogenicity and durability must be improved before advancing transmission-blocking vaccines further in clinical development. We hypothesized that the prefertilization protein Pfs230 alone or in combination with Pfs25 would improve functional activity.METHODSTransmission-blocking vaccine candidates based on gamete antigen Pfs230 or Pfs25 were conjugated with Exoprotein A, formulated in Alhydrogel, and administered to mice, rhesus macaques, and humans. Antibody levels were measured by ELISA and transmission-reducing activity was assessed by the standard membrane feeding assay.RESULTSPfs25-EPA/Alhydrogel and Pfs230D1-EPA/Alhydrogel induced similar serum functional activity in mice, but Pfs230D1-EPA induced significantly greater activity in rhesus monkeys that was enhanced by complement. In US adults, 2 vaccine doses induced complement-dependent activity in 4 of 5 Pfs230D1-EPA/Alhydrogel recipients but no significant activity in 5 Pfs25-EPA recipients, and combination with Pfs25-EPA did not increase activity over Pfs230D1-EPA alone.CONCLUSIONThe complement-dependent functional immunogenicity of Pfs230D1-EPA represents a significant improvement over Pfs25-EPA in this comparative study. The rhesus model is more predictive of the functional human immune response to Pfs230D1 than is the mouse model.TRIAL REGISTRATIONClinicalTrials.gov NCT02334462.FUNDINGIntramural Research Program of the National Institute of Allergy and Infectious Diseases, National Institutes of Health.
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Affiliation(s)
- Sara A Healy
- Laboratory of Malaria Immunology and Vaccinology, and
| | | | - Bruce J Swihart
- Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | | | - Erin E Gabriel
- Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA.,Department of Medical Epidemiology and Biostatistics, Karolinska Institute, Stockholm, Sweden
| | - Hope Decederfelt
- Pharmacy Department, Clinical Center, National Institutes of Health, Bethesda, Maryland, USA
| | | | | | - Daming Zhu
- Laboratory of Malaria Immunology and Vaccinology, and
| | - Olga Muratova
- Laboratory of Malaria Immunology and Vaccinology, and
| | - Raul Herrera
- Laboratory of Malaria Immunology and Vaccinology, and
| | | | | | | | - Irfan Zaidi
- Laboratory of Malaria Immunology and Vaccinology, and
| | | | | | - Yimin Wu
- Laboratory of Malaria Immunology and Vaccinology, and
| | - David L Narum
- Laboratory of Malaria Immunology and Vaccinology, and
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24
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Coelho CH, Tang WK, Burkhardt M, Galson JD, Muratova O, Salinas ND, Alves e Silva TL, Reiter K, MacDonald NJ, Nguyen V, Herrera R, Shimp R, Narum DL, Byrne-Steele M, Pan W, Hou X, Brown B, Eisenhower M, Han J, Jenkins BJ, Doritchamou JYA, Smelkinson MG, Vega-Rodríguez J, Trück J, Taylor JJ, Sagara I, Healy SA, Renn JP, Tolia NH, Duffy PE. A human monoclonal antibody blocks malaria transmission and defines a highly conserved neutralizing epitope on gametes. Nat Commun 2021; 12:1750. [PMID: 33741942 PMCID: PMC7979743 DOI: 10.1038/s41467-021-21955-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 02/17/2021] [Indexed: 01/31/2023] Open
Abstract
Malaria elimination requires tools that interrupt parasite transmission. Here, we characterize B cell receptor responses among Malian adults vaccinated against the first domain of the cysteine-rich 230 kDa gamete surface protein Pfs230, a key protein in sexual stage development of P. falciparum parasites. Among nine Pfs230 human monoclonal antibodies (mAbs) that we generated, one potently blocks transmission to mosquitoes in a complement-dependent manner and reacts to the gamete surface; the other eight show only low or no blocking activity. The structure of the transmission-blocking mAb in complex with vaccine antigen reveals a large discontinuous conformational epitope, specific to domain 1 of Pfs230 and comprising six structural elements in the protein. The epitope is conserved, suggesting the transmission-blocking mAb is broadly functional. This study provides a rational basis to improve malaria vaccines and develop therapeutic antibodies for malaria elimination.
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Affiliation(s)
- Camila H. Coelho
- grid.94365.3d0000 0001 2297 5165Pathogenesis and Immunity Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Wai Kwan Tang
- grid.94365.3d0000 0001 2297 5165Host-Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Martin Burkhardt
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Jacob D. Galson
- grid.7400.30000 0004 1937 0650Division of Immunology and Children’s Research Center, University Children’s Hospital Zurich, University of Zurich (UZH), Zurich, Switzerland ,Alchemab Therapeutics Ltd, 55-56 Russell Square, London, UK
| | - Olga Muratova
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Nichole D. Salinas
- grid.94365.3d0000 0001 2297 5165Host-Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Thiago Luiz Alves e Silva
- grid.94365.3d0000 0001 2297 5165Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD USA
| | - Karine Reiter
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Nicholas J. MacDonald
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Vu Nguyen
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Raul Herrera
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Richard Shimp
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - David L. Narum
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | | | - Wenjing Pan
- grid.429220.fiRepertoire Inc., Huntsville, AL USA
| | - Xiaohong Hou
- grid.429220.fiRepertoire Inc., Huntsville, AL USA
| | | | | | - Jian Han
- grid.429220.fiRepertoire Inc., Huntsville, AL USA
| | - Bethany J. Jenkins
- grid.94365.3d0000 0001 2297 5165Pathogenesis and Immunity Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Justin Y. A. Doritchamou
- grid.94365.3d0000 0001 2297 5165Pathogenesis and Immunity Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Margery G. Smelkinson
- grid.94365.3d0000 0001 2297 5165Biological Imaging Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Joel Vega-Rodríguez
- grid.94365.3d0000 0001 2297 5165Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD USA
| | - Johannes Trück
- grid.7400.30000 0004 1937 0650Division of Immunology and Children’s Research Center, University Children’s Hospital Zurich, University of Zurich (UZH), Zurich, Switzerland
| | - Justin J. Taylor
- grid.270240.30000 0001 2180 1622Fred Hutchinson Cancer Research Center, Seattle, WA USA
| | - Issaka Sagara
- Malaria Research and Training Center, University of Sciences, Techniques, and Technology, Bamako, Mali
| | - Sara A. Healy
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Jonathan P. Renn
- grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Niraj H. Tolia
- grid.94365.3d0000 0001 2297 5165Host-Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
| | - Patrick E. Duffy
- grid.94365.3d0000 0001 2297 5165Pathogenesis and Immunity Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA ,grid.94365.3d0000 0001 2297 5165Vaccine Development Unit, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD USA
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25
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Challenger JD, Olivera Mesa D, Da DF, Yerbanga RS, Lefèvre T, Cohuet A, Churcher TS. Predicting the public health impact of a malaria transmission-blocking vaccine. Nat Commun 2021; 12:1494. [PMID: 33686061 PMCID: PMC7940395 DOI: 10.1038/s41467-021-21775-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 02/11/2021] [Indexed: 11/24/2022] Open
Abstract
Transmission-blocking vaccines that interrupt malaria transmission from humans to mosquitoes are being tested in early clinical trials. The activity of such a vaccine is commonly evaluated using membrane-feeding assays. Understanding the field efficacy of such a vaccine requires knowledge of how heavily infected wild, naturally blood-fed mosquitoes are, as this indicates how difficult it will be to block transmission. Here we use data on naturally infected mosquitoes collected in Burkina Faso to translate the laboratory-estimated activity into an estimated activity in the field. A transmission dynamics model is then utilised to predict a transmission-blocking vaccine's public health impact alongside existing interventions. The model suggests that school-aged children are an attractive population to target for vaccination. Benefits of vaccination are distributed across the population, averting the greatest number of cases in younger children. Utilising a transmission-blocking vaccine alongside existing interventions could have a substantial impact against malaria.
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Affiliation(s)
- Joseph D Challenger
- Medical Research Council Centre for Global Infections Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom.
| | - Daniela Olivera Mesa
- Medical Research Council Centre for Global Infections Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Dari F Da
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - R Serge Yerbanga
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
- Institut des Sciences et Techniques, Bobo-Dioulasso, Burkina Faso
| | - Thierry Lefèvre
- MIVEGEC, University of Montpellier, CNRS, IRD, Montpellier, France
- Centre de Recherche en Écologie et Évolution de la Santé (CREES), Montpellier, France
| | - Anna Cohuet
- MIVEGEC, University of Montpellier, CNRS, IRD, Montpellier, France
| | - Thomas S Churcher
- Medical Research Council Centre for Global Infections Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
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26
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Le Manach C, Dam J, Woodland JG, Kaur G, Khonde LP, Brunschwig C, Njoroge M, Wicht KJ, Horatscheck A, Paquet T, Boyle GA, Gibhard L, Taylor D, Lawrence N, Yeo T, Mok S, Eastman RT, Dorjsuren D, Talley DC, Guo H, Simeonov A, Reader J, van der Watt M, Erlank E, Venter N, Zawada JW, Aswat A, Nardini L, Coetzer TL, Lauterbach SB, Bezuidenhout BC, Theron A, Mancama D, Koekemoer LL, Birkholtz LM, Wittlin S, Delves M, Ottilie S, Winzeler EA, von Geldern TW, Smith D, Fidock DA, Street LJ, Basarab GS, Duffy J, Chibale K. Identification and Profiling of a Novel Diazaspiro[3.4]octane Chemical Series Active against Multiple Stages of the Human Malaria Parasite Plasmodium falciparum and Optimization Efforts. J Med Chem 2021; 64:2291-2309. [PMID: 33573376 DOI: 10.1021/acs.jmedchem.1c00034] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A novel diazaspiro[3.4]octane series was identified from a Plasmodium falciparum whole-cell high-throughput screening campaign. Hits displayed activity against multiple stages of the parasite lifecycle, which together with a novel sp3-rich scaffold provided an attractive starting point for a hit-to-lead medicinal chemistry optimization and biological profiling program. Structure-activity-relationship studies led to the identification of compounds that showed low nanomolar asexual blood-stage activity (<50 nM) together with strong gametocyte sterilizing properties that translated to transmission-blocking activity in the standard membrane feeding assay. Mechanistic studies through resistance selection with one of the analogues followed by whole-genome sequencing implicated the P. falciparum cyclic amine resistance locus in the mode of resistance.
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Affiliation(s)
- Claire Le Manach
- Drug Discovery and Development Center (H3D), University of Cape Town, Rondebosch 7701, South Africa
| | - Jean Dam
- Drug Discovery and Development Center (H3D), University of Cape Town, Rondebosch 7701, South Africa
| | - John G Woodland
- Drug Discovery and Development Center (H3D), University of Cape Town, Rondebosch 7701, South Africa
| | - Gurminder Kaur
- Drug Discovery and Development Center (H3D), University of Cape Town, Rondebosch 7701, South Africa
| | - Lutete P Khonde
- Drug Discovery and Development Center (H3D), University of Cape Town, Rondebosch 7701, South Africa
| | - Christel Brunschwig
- Drug Discovery and Development Center (H3D), Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory 7925, South Africa
| | - Mathew Njoroge
- Drug Discovery and Development Center (H3D), Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory 7925, South Africa
| | - Kathryn J Wicht
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, New York 10032, United States
| | - André Horatscheck
- Drug Discovery and Development Center (H3D), University of Cape Town, Rondebosch 7701, South Africa
| | - Tanya Paquet
- Drug Discovery and Development Center (H3D), University of Cape Town, Rondebosch 7701, South Africa
| | - Grant A Boyle
- Drug Discovery and Development Center (H3D), University of Cape Town, Rondebosch 7701, South Africa
| | - Liezl Gibhard
- Drug Discovery and Development Center (H3D), Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory 7925, South Africa
| | - Dale Taylor
- Drug Discovery and Development Center (H3D), Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory 7925, South Africa
| | - Nina Lawrence
- Drug Discovery and Development Center (H3D), Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory 7925, South Africa
| | - Tomas Yeo
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, New York 10032, United States
| | - Sachel Mok
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, New York 10032, United States
| | - Richard T Eastman
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Dorjbal Dorjsuren
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Daniel C Talley
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Hui Guo
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Anton Simeonov
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Janette Reader
- Department of Biochemistry, Genetics and Microbiology, Institute for Sustainable Malaria Control, University of Pretoria, Hatfield, Pretoria 0028, South Africa
| | - Mariëtte van der Watt
- Department of Biochemistry, Genetics and Microbiology, Institute for Sustainable Malaria Control, University of Pretoria, Hatfield, Pretoria 0028, South Africa
| | - Erica Erlank
- Wits Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2193, South Africa.,Centre for Emerging Zoonotic and Parasitic Diseases, National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg 2192, South Africa
| | - Nelius Venter
- Wits Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2193, South Africa.,Centre for Emerging Zoonotic and Parasitic Diseases, National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg 2192, South Africa
| | - Jacek W Zawada
- Wits Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2193, South Africa.,Centre for Emerging Zoonotic and Parasitic Diseases, National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg 2192, South Africa
| | - Ayesha Aswat
- Wits Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2193, South Africa.,Centre for Emerging Zoonotic and Parasitic Diseases, National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg 2192, South Africa
| | - Luisa Nardini
- Wits Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2193, South Africa.,Centre for Emerging Zoonotic and Parasitic Diseases, National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg 2192, South Africa
| | - Theresa L Coetzer
- Wits Research Institute for Malaria, School of Pathology, Department of Molecular Medicine and Haematology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2193, South Africa
| | - Sonja B Lauterbach
- Wits Research Institute for Malaria, School of Pathology, Department of Molecular Medicine and Haematology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2193, South Africa
| | - Belinda C Bezuidenhout
- Wits Research Institute for Malaria, School of Pathology, Department of Molecular Medicine and Haematology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2193, South Africa
| | - Anjo Theron
- Biosciences, Council for Scientific and Industrial Research, P.O. Box 395, Pretoria 0001, South Africa
| | - Dalu Mancama
- Biosciences, Council for Scientific and Industrial Research, P.O. Box 395, Pretoria 0001, South Africa
| | - Lizette L Koekemoer
- Wits Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2193, South Africa.,Centre for Emerging Zoonotic and Parasitic Diseases, National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg 2192, South Africa
| | - Lyn-Marie Birkholtz
- Department of Biochemistry, Genetics and Microbiology, Institute for Sustainable Malaria Control, University of Pretoria, Hatfield, Pretoria 0028, South Africa
| | - Sergio Wittlin
- Swiss Tropical and Public Health Institute, Socinstrasse 57, 4002 Basel, Switzerland.,University of Basel, 4003 Basel, Switzerland
| | - Michael Delves
- Imperial College London, South Kensington, London SW7 2AZ, U.K.,London School of Hygiene and Tropical Medicine, London WC1E 7HT, U.K
| | - Sabine Ottilie
- Division of Host-Microbe Systems & Therapeutics, Department of Pediatrics, University of California San Diego, La Jolla, California 92093-076, United States
| | - Elizabeth A Winzeler
- Division of Host-Microbe Systems & Therapeutics, Department of Pediatrics, University of California San Diego, La Jolla, California 92093-076, United States
| | | | | | - David A Fidock
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, New York 10032, United States.,Division of Infectious Diseases, Department of Medicine, Columbia University Irving Medical Center, New York, New York 10032, United States
| | - Leslie J Street
- Drug Discovery and Development Center (H3D), University of Cape Town, Rondebosch 7701, South Africa
| | - Gregory S Basarab
- Drug Discovery and Development Center (H3D), University of Cape Town, Rondebosch 7701, South Africa
| | - James Duffy
- Medicines for Malaria Venture, ICC, Route de Pré-Bois 20, P.O. Box 1826, 1215 Geneva, Switzerland
| | - Kelly Chibale
- Drug Discovery and Development Center (H3D), University of Cape Town, Rondebosch 7701, South Africa.,South African Medical Research Council, Drug Discovery and Development Research Unit, Department of Chemistry and Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Rondebosch 7701, South Africa
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27
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Stopard IJ, Churcher TS, Lambert B. Estimating the extrinsic incubation period of malaria using a mechanistic model of sporogony. PLoS Comput Biol 2021; 17:e1008658. [PMID: 33591963 PMCID: PMC7909686 DOI: 10.1371/journal.pcbi.1008658] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 02/26/2021] [Accepted: 12/28/2020] [Indexed: 11/18/2022] Open
Abstract
During sporogony, malaria-causing parasites infect a mosquito, reproduce and migrate to the mosquito salivary glands where they can be transmitted the next time blood feeding occurs. The time required for sporogony, known as the extrinsic incubation period (EIP), is an important determinant of malaria transmission intensity. The EIP is typically estimated as the time for a given percentile, x, of infected mosquitoes to develop salivary gland sporozoites (the infectious parasite life stage), which is denoted by EIPx. Many mechanisms, however, affect the observed sporozoite prevalence including the human-to-mosquito transmission probability and possibly differences in mosquito mortality according to infection status. To account for these various mechanisms, we present a mechanistic mathematical model, which explicitly models key processes at the parasite, mosquito and observational scales. Fitting this model to experimental data, we find greater variation in the EIP than previously thought: we estimated the range between EIP10 and EIP90 (at 27°C) as 4.5 days compared to 0.9 days using existing statistical methods. This pattern holds over the range of study temperatures included in the dataset. Increasing temperature from 21°C to 34°C decreased the EIP50 from 16.1 to 8.8 days. Our work highlights the importance of mechanistic modelling of sporogony to (1) improve estimates of malaria transmission under different environmental conditions or disease control programs and (2) evaluate novel interventions that target the mosquito life stages of the parasite.
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Affiliation(s)
- Isaac J. Stopard
- MRC Centre for Global Infectious Disease Analysis, School of Public Health, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Thomas S. Churcher
- MRC Centre for Global Infectious Disease Analysis, School of Public Health, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Ben Lambert
- MRC Centre for Global Infectious Disease Analysis, School of Public Health, Faculty of Medicine, Imperial College London, London, United Kingdom
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28
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Patel PN, Tolia N. Structural vaccinology of malaria transmission-blocking vaccines. Expert Rev Vaccines 2021; 20:199-214. [PMID: 33430656 PMCID: PMC11077433 DOI: 10.1080/14760584.2021.1873135] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 12/16/2020] [Indexed: 02/06/2023]
Abstract
Introduction: The development of effective vaccines remains a major health priority to combat the global burden of malaria, a life-threatening disease caused by Plasmodium parasites. Transmission-blocking vaccines (TBVs) elicit antibodies that neutralize the sexual stages of the parasite in blood meals ingested by the Anopheles mosquito, interrupting parasite development in the vector host and preventing disease spread to other individuals.Areas covered: The P. falciparum gametocyte surface antigens Pfs230, Pfs48/45, and Pfs47, the parasite ookinete surface protein Pfs25, and the male gametocyte specific protein PfHAP2 are leading TBV candidates, some of which are in clinical development. The recent expansion of methodology to study monoclonal antibodies isolated directly from humans and animal models, coupled with effective measures for parasite neutralization, has provided unprecedented insight into TBV efficacy and development.Expert opinion: Available structural and functional data on antigen-monoclonal antibody (Ag-mAb) complexes, as well as epitope classification studies, have identified neutralizing epitopes that may aid vaccine development and improve protection. Here, we review the clinical prospects of TBV candidates, progress in the development of novel vaccine strategies for TBVs, and the impact of structural vaccinology in TBV design.
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Affiliation(s)
- Palak N Patel
- Host-Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Niraj Tolia
- Host-Pathogen Interactions and Structural Vaccinology Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
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29
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Ekoka E, Maharaj S, Nardini L, Dahan-Moss Y, Koekemoer LL. 20-Hydroxyecdysone (20E) signaling as a promising target for the chemical control of malaria vectors. Parasit Vectors 2021; 14:86. [PMID: 33514413 PMCID: PMC7844807 DOI: 10.1186/s13071-020-04558-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 12/19/2020] [Indexed: 01/07/2023] Open
Abstract
With the rapid development and spread of resistance to insecticides among anopheline malaria vectors, the efficacy of current World Health Organization (WHO)-approved insecticides targeting these vectors is under threat. This has led to the development of novel interventions, including improved and enhanced insecticide formulations with new targets or synergists or with added sterilants and/or antimalarials, among others. To date, several studies in mosquitoes have revealed that the 20-hydroxyecdysone (20E) signaling pathway regulates both vector abundance and competence, two parameters that influence malaria transmission. Therefore, insecticides which target 20E signaling (e.g. methoxyfenozide and halofenozide) may be an asset for malaria vector control. While such insecticides are already commercially available for lepidopteran and coleopteran pests, they still need to be approved by the WHO for malaria vector control programs. Until recently, chemicals targeting 20E signaling were considered to be insect growth regulators, and their effect was mostly studied against immature mosquito stages. However, in the last few years, promising results have been obtained by applying methoxyfenozide or halofenozide (two compounds that boost 20E signaling) to Anopheles populations at different phases of their life-cycle. In addition, preliminary studies suggest that methoxyfenozide resistance is unstable, causing the insects substantial fitness costs, thereby potentially circumventing one of the biggest challenges faced by current vector control efforts. In this review, we first describe the 20E signaling pathway in mosquitoes and then summarize the mechanisms whereby 20E signaling regulates the physiological processes associated with vector competence and vector abundance. Finally, we discuss the potential of using chemicals targeting 20E signaling to control malaria vectors.![]()
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Affiliation(s)
- Elodie Ekoka
- WITS Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa. .,Centre for Emerging, Zoonotic & Parasitic Diseases, National Institute for Communicable Diseases, Johannesburg, South Africa.
| | - Surina Maharaj
- WITS Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.,Centre for Emerging, Zoonotic & Parasitic Diseases, National Institute for Communicable Diseases, Johannesburg, South Africa
| | - Luisa Nardini
- WITS Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.,Centre for Emerging, Zoonotic & Parasitic Diseases, National Institute for Communicable Diseases, Johannesburg, South Africa
| | - Yael Dahan-Moss
- WITS Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.,Centre for Emerging, Zoonotic & Parasitic Diseases, National Institute for Communicable Diseases, Johannesburg, South Africa
| | - Lizette L Koekemoer
- WITS Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.,Centre for Emerging, Zoonotic & Parasitic Diseases, National Institute for Communicable Diseases, Johannesburg, South Africa
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30
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Multistage and transmission-blocking targeted antimalarials discovered from the open-source MMV Pandemic Response Box. Nat Commun 2021; 12:269. [PMID: 33431834 PMCID: PMC7801607 DOI: 10.1038/s41467-020-20629-8] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 12/10/2020] [Indexed: 12/30/2022] Open
Abstract
Chemical matter is needed to target the divergent biology associated with the different life cycle stages of Plasmodium. Here, we report the parallel de novo screening of the Medicines for Malaria Venture (MMV) Pandemic Response Box against Plasmodium asexual and liver stage parasites, stage IV/V gametocytes, gametes, oocysts and as endectocides. Unique chemotypes were identified with both multistage activity or stage-specific activity, including structurally diverse gametocyte-targeted compounds with potent transmission-blocking activity, such as the JmjC inhibitor ML324 and the antitubercular clinical candidate SQ109. Mechanistic investigations prove that ML324 prevents histone demethylation, resulting in aberrant gene expression and death in gametocytes. Moreover, the selection of parasites resistant to SQ109 implicates the druggable V-type H+-ATPase for the reduced sensitivity. Our data therefore provides an expansive dataset of compounds that could be redirected for antimalarial development and also point towards proteins that can be targeted in multiple parasite life cycle stages. Here, Reader et al. screen the Medicines for Malaria Venture Pandemic Response Box in parallel against Plasmodiumasexual and liver stage parasites, stage IV/V gametocytes, gametes, oocysts and as endectocides. They identify two potent transmission-blocking drugs: a histone demethylase inhibitor ML324 and the antitubercular SQ109.
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31
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Huang WC, Deng B, Mabrouk MT, Seffouh A, Ortega J, Long C, Miura K, Wu Y, Lovell JF. Particle-based, Pfs230 and Pfs25 immunization is effective, but not improved by duplexing at fixed total antigen dose. Malar J 2020; 19:309. [PMID: 32859199 PMCID: PMC7453371 DOI: 10.1186/s12936-020-03368-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 08/10/2020] [Indexed: 12/17/2022] Open
Abstract
Background The Plasmodium falciparum sexual-stage surface proteins Pfs25 and Pfs230 are antigen candidates for a malaria transmission-blocking vaccine (TBV), and have been widely investigated as such. It is not clear whether simultaneously presenting these two antigens in a particulate vaccine would enhance the transmission reducing activity (TRA) of induced antibodies. To assess this, immunization was carried out with liposomes containing synthetic lipid adjuvant monophosphoryl lipid A (MPLA), and cobalt-porphyrin-phospholipid (CoPoP), which rapidly converts recombinant, his-tagged antigens into particles. Methods His-tagged, recombinant Pfs25 and Pfs230C1 were mixed with CoPoP liposomes to form a bivalent vaccine. Antigens were fluorescently labelled to infer duplex particleization serum-stability and binding kinetics using fluorescence resonance energy transfer. Mice and rabbits were immunized with individual or duplexed particleized Pfs25 and Pfs230C1, at fixed total antigen doses. The resulting antibody responses were assessed for magnitude and TRA. Results Pfs230C1 and Pfs25 rapidly bound CoPoP liposomes to form a serum-stable, bivalent particle vaccine. In mice, immunization with 5 ng of total antigen (individual antigen or duplexed) elicited functional antibodies against Pfs25 and Pfs230. Compared to immunization with the individual antigen, Pfs25 antibody production was moderately lower for the bivalent CoPoP vaccine, whereas Pfs230C1 antibody production was not impacted. All antibodies demonstrated at least 92% inhibition in oocyst density at 750 μg/mL purified mouse IgG in the standard membrane feeding assay (SMFA). At lower IgG concentrations, the bivalent vaccine did not improve TRA; antibodies induced by particleized Pfs25 alone showed stronger function in these conditions. In rabbits, immunization with a 20 µg total antigen dose with the duplexed antigens yielded similar antibody production against Pfs25 and Pfs230 compared to immunization with a 20 µg dose of individual antigens. However, no enhanced TRA was observed with duplexing. Conclusions Pfs25, Pfs230 or the duplexed combination can readily be prepared as particulate vaccines by mixing CoPoP liposomes with soluble, recombinant antigens. This approach induces potent transmission-reducing antibodies following immunization in mice and rabbits. Immunization with bivalent, particleized, Pfs230 and Pfs25 did not yield antibodies with superior TRA compared to immunization with particleized Pfs25 as a single antigen. Altogether, duplexing antigens is straightforward and effective using CoPoP liposomes, but is likely to be more useful for targeting distinct parasite life stages.
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Affiliation(s)
- Wei-Chiao Huang
- Department of Biomedical Engineering, University at Buffalo, State University of New York, Buffalo, NY, 14260, USA
| | - Bingbing Deng
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, 20852, USA
| | - Moustafa T Mabrouk
- Department of Biomedical Engineering, University at Buffalo, State University of New York, Buffalo, NY, 14260, USA
| | - Amal Seffouh
- Department of Anatomy and Cell Biology, McGill University Montreal, Quebec, H3A 0C7, Canada
| | - Joaquin Ortega
- Department of Anatomy and Cell Biology, McGill University Montreal, Quebec, H3A 0C7, Canada
| | - Carole Long
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, 20852, USA
| | - Kazutoyo Miura
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, 20852, USA
| | - Yimin Wu
- PATH's Malaria Vaccine Initiative (MVI), Washington, DC, 20001, USA
| | - Jonathan F Lovell
- Department of Biomedical Engineering, University at Buffalo, State University of New York, Buffalo, NY, 14260, USA.
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Evaluation and modeling of direct membrane-feeding assay with Plasmodium vivax to support development of transmission blocking vaccines. Sci Rep 2020; 10:12569. [PMID: 32724063 PMCID: PMC7387523 DOI: 10.1038/s41598-020-69513-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 07/09/2020] [Indexed: 02/06/2023] Open
Abstract
Standard and direct membrane-feeding assays (SMFA and DMFA) are fundamental assays to evaluate efficacy of transmission-blocking intervention (TBI) candidates against Plasmodium falciparum and vivax. To compare different candidates precisely, it is crucial to understand the error range of measured activity, usually expressed as percent inhibition in either oocyst intensity (% transmission reducing activity, %TRA), or in prevalence of infected mosquitoes (% transmission blocking activity, %TBA). To this end, mathematical models have been proposed for P. falciparum SMFA (PfSMFA), but such study for DMFA is limited. In this study, we analyzed P. vivax DMFA (PvDMFA) data from 22,236 mosquitoes tested from 96 independent assays. While the two assays are quite different, a zero-inflated negative binomial (ZINB) model could reasonably explain the PvDMFA results, as it has for PfSMFA. Our simulation studies based on the ZINB model revealed it is better to report %TRA values with a proper error range, rather than observed %TBA both in SMFA and DMFA. Furthermore, the simulations help in designing a better assay and aid in estimating an error range of a %TRA value when the uncertainty is not reported. This study strongly supports future TBI development by providing a rational method to compare different candidates.
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Singh K, Burkhardt M, Nakuchima S, Herrera R, Muratova O, Gittis AG, Kelnhofer E, Reiter K, Smelkinson M, Veltri D, Swihart BJ, Shimp R, Nguyen V, Zhang B, MacDonald NJ, Duffy PE, Garboczi DN, Narum DL. Structure and function of a malaria transmission blocking vaccine targeting Pfs230 and Pfs230-Pfs48/45 proteins. Commun Biol 2020; 3:395. [PMID: 32709983 PMCID: PMC7381611 DOI: 10.1038/s42003-020-01123-9] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 07/03/2020] [Indexed: 12/21/2022] Open
Abstract
Proteins Pfs230 and Pfs48/45 are Plasmodium falciparum transmission-blocking (TB) vaccine candidates that form a membrane-bound protein complex on gametes. The biological role of Pfs230 or the Pfs230-Pfs48/45 complex remains poorly understood. Here, we present the crystal structure of recombinant Pfs230 domain 1 (Pfs230D1M), a 6-cysteine domain, in complex with the Fab fragment of a TB monoclonal antibody (mAb) 4F12. We observed the arrangement of Pfs230 on the surface of macrogametes differed from that on microgametes, and that Pfs230, with no known membrane anchor, may exist on the membrane surface in the absence of Pfs48/45. 4F12 appears to sterically interfere with Pfs230 function. Combining mAbs against different epitopes of Pfs230D1 or of Pfs230D1 and Pfs48/45, significantly increased TB activity. These studies elucidate a mechanism of action of the Pfs230D1 vaccine, model the functional activity induced by a polyclonal antibody response and support the development of TB vaccines targeting Pfs230D1 and Pfs230D1-Pfs48/45. With the aim to advance the development of a P. falciparum transmission blocking vaccine, Singh et al. determine the crystal structure of Pfs230D1 in complex with the Fab fragment of TB mAb 4F12. They further study the cellular localization of Pfs230 on the surface of sexual stages of parasites and the effect of combining TB mAbs against Pfs230 and Pfs48/45.
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Affiliation(s)
- Kavita Singh
- Structural Biology Section, Research Technologies Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Martin Burkhardt
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Sofia Nakuchima
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Raul Herrera
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Olga Muratova
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Apostolos G Gittis
- Structural Biology Section, Research Technologies Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Emily Kelnhofer
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Karine Reiter
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Margery Smelkinson
- Biological Imaging Section, Research Technologies Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 4 Memorial Drive, Bethesda, MD, 20814, USA
| | - Daniel Veltri
- Bioinformatics and Computational Biosciences Branch, Office of Cyber Infrastructure and Computational Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 5601 Fishers Lane, Rockville, MD, 20852, USA
| | - Bruce J Swihart
- Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 5601 Fishers Lane, Rockville, MD, 20852, USA
| | - Richard Shimp
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Vu Nguyen
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Baoshan Zhang
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20814, USA
| | - Nicholas J MacDonald
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - Patrick E Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - David N Garboczi
- Structural Biology Section, Research Technologies Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA
| | - David L Narum
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 29 Lincoln Drive, Bethesda, MD, 20892, USA.
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High Plasmodium infection intensity in naturally infected malaria vectors in Africa. Int J Parasitol 2020; 50:985-996. [PMID: 32681932 DOI: 10.1016/j.ijpara.2020.05.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 05/14/2020] [Accepted: 05/17/2020] [Indexed: 01/18/2023]
Abstract
The population dynamics of human to mosquito malaria transmission in the field has important implications for the genetics, epidemiology and control of malaria. The number of oocysts in oocyst-positive mosquitoes developing from a single, naturally acquired infectious blood meal (herein referred to as a single-feed infection load) greatly influences the efficacy of transmission blocking interventions but still remains poorly documented. During a year-long analysis of malaria parasite transmission in Burkina Faso we caught and dissected wild malaria vectors to assess Plasmodium oocyst prevalence and load (the number of oocysts counted in mosquitoes with detectable oocysts) and the prevalence of salivary gland sporozoites. This was compared with malaria endemicity in the human population, assessed in cross-sectional surveys. Data were analysed using a novel transmission mathematical model to estimate the per bite transmission probability and the average single-feed infection load for each location. The observed oocyst load and the estimated single-feed infection load in naturally infected mosquitoes were substantially higher than previous estimates (means ranging from 3.2 to 24.5 according to seasons and locations) and indicate a strong positive association between the single-feed infection load and parasite prevalence in humans. This work suggests that highly infected mosquitoes are not rare in the field and might have a greater influence on the epidemiology and genetics of the parasite, and on the efficacy of novel transmission blocking interventions.
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Parzych EM, Miura K, Long CA, Burns JM. Maintaining immunogenicity of blood stage and sexual stage subunit malaria vaccines when formulated in combination. PLoS One 2020; 15:e0232355. [PMID: 32348377 PMCID: PMC7190115 DOI: 10.1371/journal.pone.0232355] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 04/13/2020] [Indexed: 11/18/2022] Open
Abstract
Background Eradication of Plasmodium falciparum malaria will likely require a multivalent vaccine, but the development of a highly efficacious subunit-based formulation has been challenging. We previously showed that production and immunogenicity of two leading vaccine targets, PfMSP119 (blood-stage) and Pfs25 (sexual stage), could be enhanced upon genetic fusion to merozoite surface protein 8 (PfMSP8). Here, we sought to optimize a Pfs25-based formulation for use in combination with rPfMSP1/8 with the goal of maintaining the immunogenicity of each subunit. Methods Comparative mouse studies were conducted to assess the effects of adjuvant selection (Alhydrogel vs. glucopyranosyl lipid adjuvant-stable emulsion (GLA-SE)) and antigen dose (2.5 vs. 0.5 μg) on the induction of anti-Pfs25 immune responses. The antibody response (magnitude, IgG subclass profile, and transmission-reducing activity (TRA)) and cellular responses (proliferation, cytokine production) generated in response to each formulation were assessed. Similarly, immunogenicity of a bivalent vaccine containing rPfMSP1/8 and rPfs25/8 was evaluated. Results Alum-based formulations elicited strong and comparable humoral and cellular responses regardless of antigen form (unfused rPfs25 or chimeric rPfs25/8) or dose. In contrast, GLA-SE based formulations elicited differential responses as a function of both parameters, with 2.5 μg of rPfs25/8 inducing the highest titers of functional anti-Pfs25 antibodies. Based on these data, chimeric rPfs25/8 was selected and tested in a bivalent formulation with rPfMSP1/8. Strong antibody titers against Pfs25 and PfMSP119 domains were induced with GLA-SE based formulations, with no indication of antigenic competition. Conclusions We were able to generate an immunogenic bivalent vaccine designed to target multiple parasite stages that could reduce both clinical disease and parasite transmission. The use of the same PfMSP8 carrier for two different vaccine components was effective in this bivalent formulation. As such, the incorporation of additional protective targets fused to the PfMSP8 carrier into the formulation should be feasible, further broadening the protective response.
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Affiliation(s)
- Elizabeth M. Parzych
- Department of Microbiology and Immunology, Center for Molecular Parasitology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Kazutoyo Miura
- Malaria Immunology Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - Carole A. Long
- Department of Microbiology and Immunology, Center for Molecular Parasitology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
- Malaria Immunology Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, United States of America
| | - James M. Burns
- Department of Microbiology and Immunology, Center for Molecular Parasitology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
- * E-mail:
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Antibody response of a particle-inducing, liposome vaccine adjuvant admixed with a Pfs230 fragment. NPJ Vaccines 2020; 5:23. [PMID: 32218995 PMCID: PMC7080793 DOI: 10.1038/s41541-020-0173-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 02/24/2020] [Indexed: 02/07/2023] Open
Abstract
Pfs230 is a malaria transmission-blocking antigen candidate, expressed on the surface of Plasmodium falciparum gametocytes. A recombinant, his-tagged Pfs230 fragment (Pfs230C1; amino acids 443–731) formed serum-stable particles upon incubation with liposomes containing cobalt-porphyrin-phospholipid (CoPoP). In mice, immunization with Pfs230C1, admixed with the adjuvants Alum, Montanide ISA720 or CoPoP liposomes (also containing synthetic monophosphoryl lipid A; PHAD), resulted in elicitation of IgG antibodies, but only those induced with CoPoP/PHAD or ISA720 strongly reduced parasite transmission. Immunization with micrograms of Pfs230C1 adjuvanted with identical liposomes lacking cobalt (that did not induce particle formation) or Alum was less effective than immunization with nanograms of Pfs230C1 with CoPoP/PHAD. CoPoP/PHAD and ISA720 adjuvants induced antibodies with similar Pfs230C1 avidity but higher IgG2-to-IgG1 ratios than Alum, which likely contributed to enhanced functional activity. Unlike prior work with another transmission-blocking antigen (Pfs25), Pfs230C1 was found to be effectively taken up by antigen-presenting cells without particle formation. The anti-Pfs230C1 IgG response was durable in mice for 250 days following immunization with CoPoP/PHAD, as were antibody avidity and elevated IgG2-to-IgG1 ratios. Immunization of rabbits with 20 µg Pfs230C1 admixed with CoPoP/PHAD elicited antibodies that inhibited parasite transmission. Taken together, these results show that liposomes containing CoPoP and PHAD are an effective vaccine adjuvant platform for recombinant malaria transmission blocking antigens.
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Lee SM, Hickey JM, Miura K, Joshi SB, Volkin DB, King CR, Plieskatt JL. A C-terminal Pfs48/45 malaria transmission-blocking vaccine candidate produced in the baculovirus expression system. Sci Rep 2020; 10:395. [PMID: 31942034 PMCID: PMC6962329 DOI: 10.1038/s41598-019-57384-w] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Accepted: 12/30/2019] [Indexed: 11/09/2022] Open
Abstract
The Plasmodium falciparum gametocyte surface protein, Pfs48/45, is a potential target for malaria transmission-blocking vaccines. However, due to its size and complexity, expression of the full-length protein has been difficult, leading to focus on the C-terminal six cysteine domain (6C) with the use of fusion proteins to facilitate expression and folding. In this study, we utilized the baculovirus system to evaluate the expression of three Pfs48/45 proteins including the full-length protein, the 6C domain fragment and the 6C domain mutant to prevent glycosylation. Expression of the recombinant Pfs48/45 proteins was conducted in super Sf9 cells combined with the use of tunicamycin to prevent N-glycosylation. The proteins were then evaluated as immunogens in mice to demonstrate the induction of functionally active polyclonal antibody responses as measured in the standard membrane feeding assay (SMFA). Only the 6C protein was found to exhibit significant transmission-reducing activity. Further characterization of the biologically active 6C protein demonstrated it was homogeneous in terms of size, charge, conformation, absence of glycosylation, and containing proper disulfide bond pairings. This study presents an alternative expression system, without the need of a fusion protein partner, for the Pfs48/45 6C protein fragment including further evaluation as a potential transmission-blocking vaccine candidate.
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Affiliation(s)
- Shwu-Maan Lee
- PATH's Malaria Vaccine Initiative (MVI), 455 Massachusetts Avenue NW, Suite 1000, Washington, DC, 20001-2621, USA.
| | - John M Hickey
- Department of Pharmaceutical Chemistry, Vaccine Analytics and Formulation Center, University of Kansas, Lawrence, KS, 66047, USA
| | - Kazutoyo Miura
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, 20852, USA
| | - Sangeeta B Joshi
- Department of Pharmaceutical Chemistry, Vaccine Analytics and Formulation Center, University of Kansas, Lawrence, KS, 66047, USA
| | - David B Volkin
- Department of Pharmaceutical Chemistry, Vaccine Analytics and Formulation Center, University of Kansas, Lawrence, KS, 66047, USA
| | - C Richter King
- PATH's Malaria Vaccine Initiative (MVI), 455 Massachusetts Avenue NW, Suite 1000, Washington, DC, 20001-2621, USA
| | - Jordan L Plieskatt
- PATH's Malaria Vaccine Initiative (MVI), 455 Massachusetts Avenue NW, Suite 1000, Washington, DC, 20001-2621, USA
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Marini A, Zhou Y, Li Y, Taylor IJ, Leneghan DB, Jin J, Zaric M, Mekhaiel D, Long CA, Miura K, Biswas S. A Universal Plug-and-Display Vaccine Carrier Based on HBsAg VLP to Maximize Effective Antibody Response. Front Immunol 2019; 10:2931. [PMID: 31921185 PMCID: PMC6921968 DOI: 10.3389/fimmu.2019.02931] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 11/28/2019] [Indexed: 01/26/2023] Open
Abstract
Development of effective malaria vaccines requires delivery platforms to enhance the immunogenicity and efficacy of the target antigens. This is particularly challenging for transmission-blocking malaria vaccines (TBVs), and specifically for those based on the Pfs25 antigen, that need to elicit very high antibody titers to stop the parasite development in the mosquito host and its transmission. Presenting antigens to the immune system on virus-like particles (VLPs) is an efficient way to improve the quantity and quality of the immune response generated. Here we introduce for the first time a new VLP vaccine platform, based on the well-established hepatitis B surface antigen (HBsAg) fused to the SpyCatcher protein, so that the antigen of interest, linked to the SpyTag peptide, can be easily displayed on it (Plug-and-Display technology). As little as 10% of the SpyCatcher::HBsAg VLPs decorated with Pfs25::SpyTag (molar ratio) induces a higher antibody response and transmission-reducing activity in mice compared to the soluble protein, with 50 and 90% of the VLP coupled to the antigen further enhancing the response. Importantly, using this carrier that is a vaccine antigen itself could be beneficial, as we show that anti-HBsAg IgG antibodies are induced without interfering with the Pfs25-specific immune response generated. Furthermore, pre-existing anti-HBsAg immunity does not affect the antigen-specific response to Pfs25::SpyTag-SpyCatcher::HBsAg, suggesting that these VLPs can have a broad use as a vaccine platform.
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Affiliation(s)
- Arianna Marini
- Nuffield Department of Medicine, The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Yu Zhou
- Nuffield Department of Medicine, The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Yuanyuan Li
- Nuffield Department of Medicine, The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Iona J. Taylor
- Nuffield Department of Medicine, The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Darren B. Leneghan
- Nuffield Department of Medicine, The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Jing Jin
- Nuffield Department of Medicine, The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Marija Zaric
- Nuffield Department of Medicine, The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - David Mekhaiel
- Nuffield Department of Medicine, The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Carole A. Long
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Disease, National Institutes of Health, Rockville, MD, United States
| | - Kazutoyo Miura
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Disease, National Institutes of Health, Rockville, MD, United States
| | - Sumi Biswas
- Nuffield Department of Medicine, The Jenner Institute, University of Oxford, Oxford, United Kingdom
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The Pfs230 N-terminal fragment, Pfs230D1+: expression and characterization of a potential malaria transmission-blocking vaccine candidate. Malar J 2019; 18:356. [PMID: 31703583 PMCID: PMC6839146 DOI: 10.1186/s12936-019-2989-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 10/24/2019] [Indexed: 12/31/2022] Open
Abstract
Background Control and elimination of malaria can be accelerated by transmission-blocking interventions such as vaccines. A surface antigen of Plasmodium falciparum gametocytes, Pfs230, is a leading vaccine target antigen, and has recently progressed to experimental clinical trials. To support vaccine product development, an N-terminal Pfs230 antigen was designed to increase yield, as well as to improve antigen quality, integrity, and homogeneity. Methods A scalable baculovirus expression system was used to express the Pfs230D1+ construct (aa 552–731), which was subsequently purified and analysed. Pfs230D1+ was designed to avoid glycosylation and protease digestion, thereby potentially increasing homogeneity and stability. The resulting Pfs230D1+ protein was compared to a previous iteration of the Pfs230 N-terminal domain, Pfs230C1 (aa 443–731), through physiochemical characterization and in vivo analysis. The induction of functional antibody responses was confirmed via the standard membrane feeding assay (SMFA). Results Pfs230D1+ was produced and purified to an overall yield of 23 mg/L culture supernatant, a twofold yield increase over Pfs230C1. The Pfs230D1+ protein migrated as a single band via SDS-PAGE and was detected by anti-Pfs230C1 monoclonal antibodies. Evaluation by SDS-PAGE, chromatography (size-exclusion and reversed phase) and capillary isoelectric focusing demonstrated the molecule had improved homogeneity in terms of size, conformation, and charge. Intact mass spectrometry confirmed its molecular weight and that it was free of glycosylation, a key difference to the prior Pfs230C1 protein. The correct formation of the two intramolecular disulfide bonds was initially inferred by binding of a conformation specific monoclonal antibody and directly confirmed by LC/MS and peptide mapping. When injected into mice the Pfs230D1+ protein elicited antibodies that demonstrated transmission-reducing activity, via SMFA, comparable to Pfs230C1. Conclusion By elimination of an O-glycosylation site, a potential N-glycosylation site, and two proteolytic cleavage sites, an improved N-terminal Pfs230 fragment was produced, termed D1+, which is non-glycosylated, homogeneous, and biologically active. An intact protein at higher yield than that previously observed for the Pfs230C1 fragment was achieved. The results indicate that Pfs230D1+ protein produced in the baculovirus expression system is an attractive antigen for transmission-blocking vaccine development.
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Yusuf Y, Yoshii T, Iyori M, Mizukami H, Fukumoto S, Yamamoto DS, Emran TB, Amelia F, Islam A, Syafira I, Yoshida S. A Viral-Vectored Multi-Stage Malaria Vaccine Regimen With Protective and Transmission-Blocking Efficacies. Front Immunol 2019; 10:2412. [PMID: 31681301 PMCID: PMC6803381 DOI: 10.3389/fimmu.2019.02412] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 09/26/2019] [Indexed: 12/20/2022] Open
Abstract
Malaria parasites undergo several stages in their complex lifecycle. To achieve reductions in both the individual disease burden and malaria transmission within communities, a multi-stage malaria vaccine with high effectiveness and durability is a more efficacious strategy compared with a single-stage vaccine. Here, we generated viral-vectored vaccines based on human adenovirus type 5 (AdHu5) and adeno-associated virus serotype 1 (AAV1) expressing a fusion protein of the pre-erythrocytic stage Plasmodium falciparum circumsporozoite protein (PfCSP) and the transmission-blocking sexual stage P25 protein (Pfs25). A two-dose heterologous AdHu5-prime/AAV1-boost immunization regimen proved to be highly effective for both full protection and transmission-blocking activity against transgenic P. berghei parasites expressing the corresponding P. falciparum antigens in mice. Remarkably, the immunization regimen induced antibody responses to both PfCSP and Pfs25 for over 9 months after the boosting and also maintained high levels of transmission-reducing activity (TRA: >99%) during that period, as evaluated by a direct feeding assay. If similar efficacies on P. falciparum can be shown following vaccination of humans, we propose that this multi-stage malaria vaccine regimen will be a powerful tool for malaria control, providing greater overall protection and cost-effectiveness than single-stage vaccines.
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Affiliation(s)
- Yenni Yusuf
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa University, Kanazawa, Japan
- Department of Parasitology, Faculty of Medicine, University of Hasanuddin, Makassar, Indonesia
| | - Tatsuya Yoshii
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa University, Kanazawa, Japan
| | - Mitsuhiro Iyori
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa University, Kanazawa, Japan
| | - Hiroaki Mizukami
- Division of Genetics Therapeutics, Centre for Molecular Medicine, Jichi Medical University, Shimotsuke, Japan
| | - Shinya Fukumoto
- National Research Centre for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Japan
| | - Daisuke S. Yamamoto
- Division of Medical Zoology, Department of Infection and Immunity, Jichi Medical University, Shimotsuke, Japan
| | - Talha Bin Emran
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa University, Kanazawa, Japan
| | - Fitri Amelia
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa University, Kanazawa, Japan
| | - Ashekul Islam
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa University, Kanazawa, Japan
| | - Intan Syafira
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa University, Kanazawa, Japan
| | - Shigeto Yoshida
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa University, Kanazawa, Japan
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McLeod B, Miura K, Scally SW, Bosch A, Nguyen N, Shin H, Kim D, Volkmuth W, Rämisch S, Chichester JA, Streatfield S, Woods C, Schief WR, Emerling D, King CR, Julien JP. Potent antibody lineage against malaria transmission elicited by human vaccination with Pfs25. Nat Commun 2019; 10:4328. [PMID: 31551421 PMCID: PMC6760140 DOI: 10.1038/s41467-019-11980-6] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 08/14/2019] [Indexed: 01/13/2023] Open
Abstract
Transmission-blocking vaccines have the potential to be key contributors to malaria elimination. Such vaccines elicit antibodies that inhibit parasites during their development in Anopheles mosquitoes, thus breaking the cycle of transmission. To date, characterization of humoral responses to Plasmodium falciparum transmission-blocking vaccine candidate Pfs25 has largely been conducted in pre-clinical models. Here, we present molecular analyses of human antibody responses generated in a clinical trial evaluating Pfs25 vaccination. From a collection of monoclonal antibodies with transmission-blocking activity, we identify the most potent transmission-blocking antibody yet described against Pfs25; 2544. The interactions of 2544 and three other antibodies with Pfs25 are analyzed by crystallography to understand structural requirements for elicitation of human transmission-blocking responses. Our analyses provide insights into Pfs25 immunogenicity and epitope potency, and detail an affinity maturation pathway for a potent transmission-blocking antibody in humans. Our findings can be employed to guide the design of improved malaria transmission-blocking vaccines. Pfs25 is a transmission-blocking vaccine candidate for Plasmodium. Here, McLeod et al. analyze the antibody response to Pfs25 in sera from a clinical trial evaluating a Pfs25 vaccine candidate, identify a potent transmission-blocking antibody and determine recognized epitopes on Pfs25.
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Affiliation(s)
- Brandon McLeod
- Program in Molecular Medicine, The Hospital for Sick Children Research Institute, 686 Bay Street, Toronto, ON, M5G 0A4, Canada.,Department of Biochemistry, University of Toronto, 1 King's College Circle, Toronto, ON, M5S 1A8, Canada
| | - Kazutoyo Miura
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 12735 Twinbrook Parkway, Rockville, MD, 20852, USA
| | - Stephen W Scally
- Program in Molecular Medicine, The Hospital for Sick Children Research Institute, 686 Bay Street, Toronto, ON, M5G 0A4, Canada
| | - Alexandre Bosch
- Program in Molecular Medicine, The Hospital for Sick Children Research Institute, 686 Bay Street, Toronto, ON, M5G 0A4, Canada
| | - Ngan Nguyen
- Atreca, 500 Saginaw Drive, Redwood City, CA, 94063-4750, USA
| | - Hanjun Shin
- Atreca, 500 Saginaw Drive, Redwood City, CA, 94063-4750, USA
| | - Dongkyoon Kim
- Atreca, 500 Saginaw Drive, Redwood City, CA, 94063-4750, USA
| | - Wayne Volkmuth
- Atreca, 500 Saginaw Drive, Redwood City, CA, 94063-4750, USA
| | - Sebastian Rämisch
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Jessica A Chichester
- Gene Therapy Program & Orphan Disease Center, Perelman School of Medicine, The University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Stephen Streatfield
- Fraunhofer USA Center for Molecular Biotechnology CMB, 9 Innovation Way, Newark, DE, 19711, USA
| | - Colleen Woods
- PATH's Malaria Vaccine Initiative, 455 Massachusetts Avenue NW Suite 1000, Washington, DC, 20001, USA
| | - William R Schief
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Daniel Emerling
- Atreca, 500 Saginaw Drive, Redwood City, CA, 94063-4750, USA
| | - C Richter King
- PATH's Malaria Vaccine Initiative, 455 Massachusetts Avenue NW Suite 1000, Washington, DC, 20001, USA
| | - Jean-Philippe Julien
- Program in Molecular Medicine, The Hospital for Sick Children Research Institute, 686 Bay Street, Toronto, ON, M5G 0A4, Canada. .,Department of Biochemistry, University of Toronto, 1 King's College Circle, Toronto, ON, M5S 1A8, Canada. .,Department of Immunology, University of Toronto, 1 King's College Circle, Toronto, ON, M5S 1A8, Canada.
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Chan JA, Wetzel D, Reiling L, Miura K, Drew DR, Gilson PR, Anderson DA, Richards JS, Long CA, Suckow M, Jenzelewski V, Tsuboi T, Boyle MJ, Piontek M, Beeson JG. Malaria vaccine candidates displayed on novel virus-like particles are immunogenic and induce transmission-blocking activity. PLoS One 2019; 14:e0221733. [PMID: 31504038 PMCID: PMC6736250 DOI: 10.1371/journal.pone.0221733] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Accepted: 08/13/2019] [Indexed: 01/23/2023] Open
Abstract
The development of effective malaria vaccines remains a global health priority. Currently, the most advanced vaccine, known as RTS,S, has only shown modest efficacy in clinical trials. Thus, the development of more efficacious vaccines by improving the formulation of RTS,S for increased efficacy or to interrupt malaria transmission are urgently needed. The RTS,S vaccine is based on the presentation of a fragment of the sporozoite antigen on the surface of virus-like particles (VLPs) based on human hepatitis B virus (HBV). In this study, we have developed and evaluated a novel VLP platform based on duck HBV (known as Metavax) for malaria vaccine development. This platform can incorporate large and complex proteins into VLPs and is produced in a Hansenula cell line compatible with cGMP vaccine production. Here, we have established the expression of leading P. falciparum malaria vaccine candidates as VLPs. This includes Pfs230 and Pfs25, which are candidate transmission-blocking vaccine antigens. We demonstrated that the VLPs effectively induce antibodies to malaria vaccine candidates with minimal induction of antibodies to the duck-HBV scaffold antigen. Antibodies to Pfs230 also recognised native protein on the surface of gametocytes, and antibodies to both Pfs230 and Pfs25 demonstrated transmission-reducing activity in standard membrane feeding assays. These results establish the potential utility of this VLP platform for malaria vaccines, which may be suitable for the development of multi-component vaccines that achieve high vaccine efficacy and transmission-blocking immunity.
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Affiliation(s)
- Jo-Anne Chan
- Burnet Institute, Life Sciences, Melbourne, VIC, Australia
- Department of Immunology, Central Clinical School, Monash University, VIC, Australia
| | - David Wetzel
- ARTES Biotechnology GmbH, Langenfeld, Germany
- Technical University of Dortmund, Laboratory of Plant and Process Design, Dortmund, Germany
| | - Linda Reiling
- Burnet Institute, Life Sciences, Melbourne, VIC, Australia
| | - Kazutoyo Miura
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Disease, National Institutes of Health, Rockville, Maryland, United States of America
| | - Damien R. Drew
- Burnet Institute, Life Sciences, Melbourne, VIC, Australia
| | - Paul R. Gilson
- Burnet Institute, Life Sciences, Melbourne, VIC, Australia
| | | | - Jack S. Richards
- Burnet Institute, Life Sciences, Melbourne, VIC, Australia
- Department of Medicine, University of Melbourne, VIC, Australia
| | - Carole A. Long
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Disease, National Institutes of Health, Rockville, Maryland, United States of America
| | | | | | - Takafumi Tsuboi
- Proteo-Science Centre, Ehime University, Matsuyama, Ehime, Japan
| | - Michelle J. Boyle
- Immunology Department, QIMR-Berghofer Medical Research Institute, Herston, QLD, Australia
| | | | - James G. Beeson
- Burnet Institute, Life Sciences, Melbourne, VIC, Australia
- Department of Immunology, Central Clinical School, Monash University, VIC, Australia
- Department of Medicine, University of Melbourne, VIC, Australia
- * E-mail:
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43
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Abstract
Malaria vaccine development has rapidly advanced in the past decade. The very first phase 3 clinical trial of the RTS,S vaccine was completed with over 15,000 African infants and children, and pilot implementation studies are underway. Next-generation candidate vaccines using novel antigens, platforms, or approaches targeting different and/or multiple stages of the Plasmodium life cycle are being tested. Many candidates, in various stages of development, promise enhanced efficacy of long duration and broad protection against genetically diverse malaria strains, with a few studies under way in target populations in endemic areas. Malaria vaccines together with other interventions promise interruption and eventual elimination of malaria in endemic areas.
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Affiliation(s)
- Matthew B Laurens
- Department of Pediatrics, University of Maryland School of Medicine, Baltimore 21201, Maryland, USA; .,Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland 21201, USA.,Malaria Research Program, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore 21201, Maryland, USA
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44
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Mamedov T, Cicek K, Miura K, Gulec B, Akinci E, Mammadova G, Hasanova G. A Plant-Produced in vivo deglycosylated full-length Pfs48/45 as a Transmission-Blocking Vaccine Candidate against malaria. Sci Rep 2019; 9:9868. [PMID: 31285498 PMCID: PMC6614448 DOI: 10.1038/s41598-019-46375-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Accepted: 06/27/2019] [Indexed: 12/25/2022] Open
Abstract
Pfs48/45 is a leading antigen candidate for a transmission blocking (TB) vaccine. However, efforts to produce affordable, safe and correctly folded full-length Pfs48/45 using different protein expression systems have not produced an antigen with satisfactory TB activity. Pfs48/45 has 16 cysteines involved in disulfide bond formation, and the correct formation is critical for proper folding and induction of TB antibodies. Moreover, Pfs48⁄45 is not a glycoprotein in the native hosts, but contains potential glycosylation sites, which are aberrantly glycosylated during expression in eukaryotic systems. Here, we demonstrate for the first time that full length, Endo H in vivo enzymatic deglycosylated Pfs48/45 antigen is produced at a high level in plants and is structurally stable at elevated temperatures. Sera from mice immunized with this antigen showed strong inhibition in SMFA. Thus, Endo H in vivo enzymatic deglycosylated Pfs48/45 is a promising candidate for the development of an affordable TB vaccine, which may have the potential to save millions.
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Affiliation(s)
- Tarlan Mamedov
- Akdeniz University, Department of Agricultural Biotechnology, Dumlupınar Boulevard 07058 Campus, Antalya, Turkey.
- Azerbaijan National Academy of Science, Department of Biology and Medical Science, 24 Istiglaliyyat Street, Baku, Azerbaijan.
| | - Kader Cicek
- Akdeniz University, Department of Agricultural Biotechnology, Dumlupınar Boulevard 07058 Campus, Antalya, Turkey
| | - Kazutoyo Miura
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 12735 Twinbrook Parkway, Rockville, MD, USA
| | - Burcu Gulec
- Akdeniz University, Department of Agricultural Biotechnology, Dumlupınar Boulevard 07058 Campus, Antalya, Turkey
| | - Ersin Akinci
- Akdeniz University, Department of Agricultural Biotechnology, Dumlupınar Boulevard 07058 Campus, Antalya, Turkey
| | - Gunay Mammadova
- Akdeniz University, Department of Agricultural Biotechnology, Dumlupınar Boulevard 07058 Campus, Antalya, Turkey
| | - Gulnara Hasanova
- Akdeniz University, Department of Agricultural Biotechnology, Dumlupınar Boulevard 07058 Campus, Antalya, Turkey
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45
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Abstract
In the progression of the life cycle of Plasmodium falciparum, a small proportion of asexual parasites differentiate into male or female sexual forms called gametocytes. Just like their asexual counterparts, gametocytes are contained within the infected host's erythrocytes (RBCs). However, unlike their asexual partners, they do not exit the RBC until they are taken up in a blood meal by a mosquito. In the mosquito midgut, they are stimulated to emerge from the RBC, undergo fertilization, and ultimately produce tens of thousands of sporozoites that are infectious to humans. This transmission cycle can be blocked by antibodies targeting proteins exposed on the parasite surface in the mosquito midgut, a process that has led to the development of candidate transmission-blocking vaccines (TBV), including some that are in clinical trials. Here we review the leading TBV antigens and highlight the ongoing search for additional gametocyte/gamete surface antigens, as well as antigens on the surfaces of gametocyte-infected erythrocytes, which can potentially become a new group of TBV candidates.
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46
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Miura K, Swihart BJ, Deng B, Zhou L, Pham TP, Diouf A, Fay MP, Long CA. Strong concordance between percent inhibition in oocyst and sporozoite intensities in a Plasmodium falciparum standard membrane-feeding assay. Parasit Vectors 2019; 12:206. [PMID: 31060594 PMCID: PMC6501457 DOI: 10.1186/s13071-019-3470-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Accepted: 04/29/2019] [Indexed: 11/22/2022] Open
Abstract
Background Effective malaria transmission-blocking vaccines (TBVs) can support malaria eradication programmes, and the standard membrane-feeding assay (SMFA) has been used as a “gold standard” assay for TBV development. However, in SMFA, the inhibitory activity is commonly measured at oocyst stage of parasites, while it is the sporozoites which transmit malaria from a mosquito to a human. A handful of studies have shown that there is a positive correlation between oocyst and sporozoite intensities. However, no study has been completed to compare inhibition levels in oocyst and sporozoite intensities in the presence of transmission-blocking (TB) antibodies. Results Plasmodium falciparum NF54 gametocytes were fed to Anopheles stephensi mosquitoes with or without anti-Pfs25 or anti-Pfs48/45 TB antibodies in 15 independent assays. For each group, a portion of the mosquitoes was dissected for oocyst counts (day 8 after feed), and a portion of the remaining mosquitoes was dissected for sporozoite counts (day 16). This study covered a large range of oocyst and sporozoite intensities: 0.2 to 80.5 on average for oocysts, and 141 to 77,417 for sporozoites. The sporozoite data were well explained by a zero-inflated negative binomial model, regardless of the presence or absence of TB antibodies. Inhibition levels in both oocyst and sporozoite intensities were determined within the same groups in 9 independent assays. When the level of inhibition in sporozoite number (expressed as Log Mean Ratio, LMR; average number in a control group was divided by the one in a test group, then took a log of the ratio) was plotted against LMR in oocyst number, the best-fit slope of a linear regression was not different from 1 (the best estimate, 1.08; 95% confidence interval, 0.87 to 1.29). Furthermore, a Bland–Altman analysis showed a strong agreement between inhibitions in oocysts and in sporozoites. Conclusions The results indicate that percent inhibition in oocyst intensity of a test sample can be directly converted to % inhibition in sporozoite intensity in P. falciparum SMFA. Therefore, if sporozoite intensity determines transmission rate from mosquitoes to humans, the percent inhibition in oocyst intensity measured by SMFA can be used to estimate the TBV efficacy. Electronic supplementary material The online version of this article (10.1186/s13071-019-3470-3) contains supplementary material, which is available to authorized users.
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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, 12735 Twinbrook Parkway, Rockville, MD, 20852, USA.
| | - Bruce J Swihart
- Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 5601 Fishers Lane, Rockville, MD, 20852, USA
| | - Bingbing Deng
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 12735 Twinbrook Parkway, Rockville, MD, 20852, USA
| | - Luwen Zhou
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 12735 Twinbrook Parkway, Rockville, MD, 20852, USA
| | - Thao P Pham
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 12735 Twinbrook Parkway, Rockville, MD, 20852, USA
| | - Ababacar Diouf
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 12735 Twinbrook Parkway, Rockville, MD, 20852, USA
| | - Michael P Fay
- Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 5601 Fishers Lane, Rockville, MD, 20852, USA
| | - Carole A Long
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 12735 Twinbrook Parkway, Rockville, MD, 20852, USA
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47
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Yusuf Y, Yoshii T, Iyori M, Yoshida K, Mizukami H, Fukumoto S, Yamamoto DS, Alam A, Emran TB, Amelia F, Islam A, Otsuka H, Takashima E, Tsuboi T, Yoshida S. Adeno-Associated Virus as an Effective Malaria Booster Vaccine Following Adenovirus Priming. Front Immunol 2019; 10:730. [PMID: 31024558 PMCID: PMC6460511 DOI: 10.3389/fimmu.2019.00730] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 03/19/2019] [Indexed: 12/12/2022] Open
Abstract
An ideal malaria vaccine platform should potently induce protective immune responses and block parasite transmission from mosquito to human, and it should maintain these effects for an extended period. Here, we have focused on vaccine development based on adeno-associated virus serotype 1 (AAV1), a viral vector widely studied in the field of clinical gene therapy that is able to induce long-term transgene expression without causing toxicity in vivo. Our results show the potential utility of AAV1 vectors as an extremely potent booster vaccine to induce durable immunity when combined with an adenovirus-priming vaccine in a rodent malaria model. We generated a series of recombinant AAV1s and human adenovirus type 5 (AdHu5) expressing either Plasmodium falciparum circumsporozoite protein (PfCSP) or P25 (Pfs25) protein. Heterologous two-dose immunization with an AdHu5-prime and AAV1-boost (AdHu5-AAV1) elicited robust and durable PfCSP- or Pfs25-specific functional antibodies over 280 days. Regarding protective efficacy, AdHu5-AAV1 PfCSP achieved high sterile protection (up to 80% protection rate) against challenge with transgenic Plasmodium berghei sporozoites expressing PfCSP. When examining transmission-blocking (TB) efficacy, we found that immunization with AdHu5-AAV1 Pfs25 maintained TB activity in vivo against transgenic P. berghei expressing Pfs25 for 287 days (99% reduction in oocyst intensity, 85% reduction in oocyst prevalence). Our data indicate that AAV1-based malaria vaccines can confer potent and durable protection as well as TB efficacy when administered following an AdHu5 priming vaccine, supporting the further evaluation of this regimen in clinical trials as a next-generation malaria vaccine platform.
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Affiliation(s)
- Yenni Yusuf
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa University, Kanazawa, Japan
- Department of Parasitology, Faculty of Medicine, University of Hasanuddin, Makassar, Indonesia
| | - Tatsuya Yoshii
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa University, Kanazawa, Japan
| | - Mitsuhiro Iyori
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa University, Kanazawa, Japan
| | - Kunitaka Yoshida
- Kanazawa University Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Japan
| | - Hiroaki Mizukami
- Division of Gene therapy, Jichi Medical University, Shimotsuke, Japan
| | - Shinya Fukumoto
- National Research Centre for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Japan
| | - Daisuke S. Yamamoto
- Division of Medical Zoology, Department of Infection and Immunity, Jichi Medical University, Shimotsuke, Japan
| | - Asrar Alam
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa University, Kanazawa, Japan
| | - Talha Bin Emran
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa University, Kanazawa, Japan
| | - Fitri Amelia
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa University, Kanazawa, Japan
| | - Ashekul Islam
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa University, Kanazawa, Japan
| | - Hiromu Otsuka
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa University, Kanazawa, Japan
| | - Eizo Takashima
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Japan
| | - Takafumi Tsuboi
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Japan
| | - Shigeto Yoshida
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kanazawa University, Kanazawa, Japan
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48
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Identification of domains within Pfs230 that elicit transmission blocking antibody responses. Vaccine 2019; 37:1799-1806. [PMID: 30824357 PMCID: PMC6708081 DOI: 10.1016/j.vaccine.2019.02.021] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 01/23/2019] [Accepted: 02/05/2019] [Indexed: 11/23/2022]
Abstract
A transmission-blocking vaccine (TBV) against Plasmodium falciparum is likely to be a valuable tool in a malaria eradication program. Pfs230 is one of the major TBV candidates, and multiple Pfs230-based vaccines induced antibodies, which prevented oocyst formation in mosquitoes as determined by a standard membrane-feeding assay (SMFA). Pfs230 is a >300 kDa protein consisting of 14 cysteine motif (CM) domains, and the size and cysteine-rich nature of the molecule have hampered its production as an intact protein. Except for one early study with maltose-binding protein fusion Pfs230 constructs expressed in Esherichia coli, all other studies have focused on only the first four CM domains in the Pfs230 molecule. To identify all possible TBV candidate domains, we systematically produced either single-CM-domain (a total of 14), 2-CM-domain (7), or 4-CM-domain (6) recombinant protein fragments using a eukaryotic wheat germ cell-free expression system (WGCFS). In addition, two more constructs which covered previously published regions, and an N-terminal prodomain construct spanning the natural cleavage site of Pfs230 were produced. Antisera against each fragment were generated in mice and we evaluated the reactivity to native Pfs230 protein by Western blots and immunofluorescence assay (IFA), and functionality by SMFA. All 30 WGCFS-produced Pfs230 constructs were immunogenic in mice. Approximately half of the mouse antibodies specifically recognized native Pfs230 by Western blots with variable band intensities. Among them, seven antibodies showed higher reactivities against native Pfs230 determined by IFA. Interestingly, antibodies against all protein fragments containing CM domain 1 displayed strong inhibitions in SMFA, while antibodies generated using constructs without CM domain 1 showed no inhibition. The results strongly support the concept that future Pfs230-based vaccine development should focus on the Pfs230 CM domain 1.
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49
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Abstract
The development of highly effective and durable vaccines against the human malaria parasites Plasmodium falciparum and P. vivax remains a key priority. Decades of endeavor have taught that achieving this goal will be challenging; however, recent innovation in malaria vaccine research and a diverse pipeline of novel vaccine candidates for clinical assessment provides optimism. With first-generation pre-erythrocytic vaccines aiming for licensure in the coming years, it is important to reflect on how next-generation approaches can improve on their success. Here we review the latest vaccine approaches that seek to prevent malaria infection, disease, and transmission and highlight some of the major underlying immunological and molecular mechanisms of protection. The synthesis of rational antigen selection, immunogen design, and immunization strategies to induce quantitatively and qualitatively improved immune effector mechanisms offers promise for achieving sustained high-level protection.
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50
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Stone W, Bousema T, Sauerwein R, Drakeley C. Two-Faced Immunity? The Evidence for Antibody Enhancement of Malaria Transmission. Trends Parasitol 2018; 35:140-153. [PMID: 30573175 DOI: 10.1016/j.pt.2018.11.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 11/15/2018] [Accepted: 11/15/2018] [Indexed: 10/27/2022]
Abstract
Plasmodium gametocytes can induce an immune response in humans that interferes with the development of sexual-stage parasites in the mosquito gut. Many early studies of the sexual-stage immune response noted that mosquito infection could be enhanced as well as reduced by immune sera. For Plasmodium falciparum, these reports are scarce, and the phenomenon is generally regarded as a methodological artefact. Plasmodium transmission enhancement (TE) remains contentious, but the clinical development of transmission-blocking vaccines based on sexual-stage antigens requires that it is further studied. In this essay, we review the early literature on the sexual-stage immune response and transmission-modulating immunity. We discuss hypotheses for the mechanism of TE, suggest experiments to prove or disprove its existence, and discuss its possible implications.
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Affiliation(s)
- Will Stone
- Department of Immunology and Infection, London School of Hygiene and Tropical Medicine, Keppel Street, London, UK.
| | - Teun Bousema
- Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Robert Sauerwein
- Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Chris Drakeley
- Department of Immunology and Infection, London School of Hygiene and Tropical Medicine, Keppel Street, London, UK
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