1
|
Thai E, Murugan R, Binter Š, Burn Aschner C, Prieto K, Kassardjian A, Obraztsova AS, Kang RW, Flores-Garcia Y, Mathis-Torres S, Li K, Horn GQ, Huntwork RHC, Bolscher JM, de Bruijni MHC, Sauerwein R, Dennison SM, Tomaras GD, Zavala F, Kellam P, Wardemann H, Julien JP. Molecular determinants of cross-reactivity and potency by VH3-33 antibodies against the Plasmodium falciparum circumsporozoite protein. Cell Rep 2023; 42:113330. [PMID: 38007690 PMCID: PMC10720262 DOI: 10.1016/j.celrep.2023.113330] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Revised: 09/29/2023] [Accepted: 10/06/2023] [Indexed: 11/27/2023] Open
Abstract
IGHV3-33-encoded antibodies are prevalent in the human humoral response against the Plasmodium falciparum circumsporozoite protein (PfCSP). Among VH3-33 antibodies, cross-reactivity between PfCSP major repeat (NANP), minor (NVDP), and junctional (NPDP) motifs is associated with high affinity and potent parasite inhibition. However, the molecular basis of antibody cross-reactivity and the relationship with efficacy remain unresolved. Here, we perform an extensive structure-function characterization of 12 VH3-33 anti-PfCSP monoclonal antibodies (mAbs) with varying degrees of cross-reactivity induced by immunization of mice expressing a human immunoglobulin gene repertoire. We identify residues in the antibody paratope that mediate cross-reactive binding and delineate four distinct epitope conformations induced by antibody binding, with one consistently associated with high protective efficacy and another that confers comparably potent inhibition of parasite liver invasion. Our data show a link between molecular features of cross-reactive VH3-33 mAb binding to PfCSP and mAb potency, relevant for the development of antibody-based interventions against malaria.
Collapse
Affiliation(s)
- Elaine Thai
- Program in Molecular Medicine, The Hospital for Sick Children Research Institute, Toronto, ON M5G 0A4, Canada; Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Rajagopal Murugan
- B Cell Immunology, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Špela Binter
- Kymab Ltd./Sanofi, The Bennet Building (B930), Babraham Research Campus, Cambridge CB22 3AT, UK; RQ Biotechnology Limited, 7th Floor Lynton House, 7-12 Tavistock Square, London WC1H 9LT, UK
| | - Clare Burn Aschner
- Program in Molecular Medicine, The Hospital for Sick Children Research Institute, Toronto, ON M5G 0A4, Canada
| | - Katherine Prieto
- Program in Molecular Medicine, The Hospital for Sick Children Research Institute, Toronto, ON M5G 0A4, Canada
| | - Audrey Kassardjian
- Program in Molecular Medicine, The Hospital for Sick Children Research Institute, Toronto, ON M5G 0A4, Canada; Department of Immunology, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Anna S Obraztsova
- B Cell Immunology, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany; Biosciences Faculty, University of Heidelberg, 69117 Heidelberg, Germany
| | - Ryu Won Kang
- Program in Molecular Medicine, The Hospital for Sick Children Research Institute, Toronto, ON M5G 0A4, Canada; Department of Immunology, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Yevel Flores-Garcia
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Shamika Mathis-Torres
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Kan Li
- Departments of Surgery, Integrative Immunobiology, Molecular Genetics, and Microbiology, Center for Human Systems Immunology, Duke University, Durham, NC 27710, USA
| | - Gillian Q Horn
- Departments of Surgery, Integrative Immunobiology, Molecular Genetics, and Microbiology, Center for Human Systems Immunology, Duke University, Durham, NC 27710, USA
| | - Richard H C Huntwork
- Departments of Surgery, Integrative Immunobiology, Molecular Genetics, and Microbiology, Center for Human Systems Immunology, Duke University, Durham, NC 27710, USA
| | | | | | | | - S Moses Dennison
- Departments of Surgery, Integrative Immunobiology, Molecular Genetics, and Microbiology, Center for Human Systems Immunology, Duke University, Durham, NC 27710, USA
| | - Georgia D Tomaras
- Departments of Surgery, Integrative Immunobiology, Molecular Genetics, and Microbiology, Center for Human Systems Immunology, Duke University, Durham, NC 27710, USA
| | - Fidel Zavala
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Paul Kellam
- Kymab Ltd./Sanofi, The Bennet Building (B930), Babraham Research Campus, Cambridge CB22 3AT, UK; RQ Biotechnology Limited, 7th Floor Lynton House, 7-12 Tavistock Square, London WC1H 9LT, UK; Department of Infectious Diseases, Faculty of Medicine, Imperial College London, London SW7 2BX, UK
| | - Hedda Wardemann
- B Cell Immunology, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany.
| | - Jean-Philippe Julien
- Program in Molecular Medicine, The Hospital for Sick Children Research Institute, Toronto, ON M5G 0A4, Canada; Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada; Department of Immunology, University of Toronto, Toronto, ON M5S 1A8, Canada.
| |
Collapse
|
2
|
Nicholas J, Kolli SK, Subramani PA, De SL, Ogbondah MM, Barnes SJ, Ntumngia FB, Adams JH. Comparative analyses of functional antibody-mediated inhibition with anti-circumsporozoite monoclonal antibodies against transgenic Plasmodium berghei. Malar J 2023; 22:335. [PMID: 37936181 PMCID: PMC10629016 DOI: 10.1186/s12936-023-04765-2] [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: 06/21/2023] [Accepted: 10/24/2023] [Indexed: 11/09/2023] Open
Abstract
BACKGROUND Acquired functional inhibitory antibodies are one of several humoral immune mechanisms used to neutralize foreign pathogens. In vitro bioassays are useful tools for quantifying antibody-mediated inhibition and evaluating anti-parasite immune antibodies. However, a gap remains in understanding of how antibody-mediated inhibition in vitro translates to inhibition in vivo. In this study, two well-characterized transgenic Plasmodium berghei parasite lines, PbmCh-luc and Pb-PfCSP(r), and murine monoclonal antibodies (mAbs) specific to P. berghei and Plasmodium falciparum circumsporozoite protein (CSP), 3D11 and 2A10, respectively, were used to evaluate antibody-mediated inhibition of parasite development in both in vitro and in vivo functional assays. METHODS IC50 values of mAbs were determined using an established inhibition of liver-stage development assay (ILSDA). For the in vivo inhibition assay, mice were passively immunized by transfer of the mAbs and subsequently challenged with 5.0 × 103 sporozoites via tail vein injection. The infection burden in both assays was quantified by luminescence and qRT-PCR of P. berghei 18S rRNA normalized to host GAPDH. RESULTS The IC50 values quantified by relative luminescence of mAbs 3D11 and 2A10 were 0.396 µg/ml and 0.093 µg/ml, respectively, against transgenic lines in vitro. Using the highest (> 90%) inhibitory antibody concentrations in a passive transfer, an IC50 of 233.8 µg/ml and 181.5 µg/ml for mAbs 3D11 and 2A10, respectively, was observed in vivo. At 25 µg (250 µg/ml), the 2A10 antibody significantly inhibited liver burden in mice compared to control. Additionally, qRT-PCR of P. berghei 18S rRNA served as a secondary validation of liver burden quantification. CONCLUSIONS Results from both experimental models, ILSDA and in vivo challenge, demonstrated that increased concentrations of the homologous anti-CSP repeat mAbs increased parasite inhibition. However, differences in antibody IC50 values between parasite lines did not allow a direct correlation between the inhibition of sporozoite invasion in vitro by ILSDA and the inhibition of mouse liver stage burden. Further studies are needed to establish the conditions for confident predictions for the in vitro ILSDA to be a predictor of in vivo outcomes using this model system.
Collapse
Affiliation(s)
- Justin Nicholas
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Tampa, FL, 33612, USA
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL, 33612, USA
| | - Surendra Kumar Kolli
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Tampa, FL, 33612, USA
| | - Pradeep Annamalai Subramani
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Tampa, FL, 33612, USA
| | - Sai Lata De
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Tampa, FL, 33612, USA
- Department of Infectious Disease & Immunology, College of Veterinary Medicine, University of Florida, Gainesville, FL, 32611, USA
| | - Madison M Ogbondah
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Tampa, FL, 33612, USA
| | - Samantha J Barnes
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Tampa, FL, 33612, USA
| | - Francis Babila Ntumngia
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Tampa, FL, 33612, USA
| | - John H Adams
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Tampa, FL, 33612, USA.
| |
Collapse
|
3
|
Genito CJ, Brooks K, Smith A, Ryan E, Soto K, Li Y, Warter L, Dutta S. Protective antibody threshold of RTS,S/AS01 malaria vaccine correlates antigen and adjuvant dose in mouse model. NPJ Vaccines 2023; 8:114. [PMID: 37563255 PMCID: PMC10415390 DOI: 10.1038/s41541-023-00714-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 08/01/2023] [Indexed: 08/12/2023] Open
Abstract
Mouse models are useful for the early down-selection of malaria vaccine candidates. The Walter Reed Army Institute of Research has optimized a transgenic Plasmodium berghei sporozoite challenge model to compare the efficacy of Plasmodium falciparum circumsporozoite protein (CSP) vaccines. GSK's RTS,S vaccine formulated in the adjuvant AS01 can protect malaria-naïve individuals against malaria. We report that the RTS,S/AS01 vaccine induces high level sterile protection in our mouse model. Down titration of the antigen at a constant AS01 dose revealed a potent antigen dose-sparing effect and the superiority of RTS,S/AS01 over a soluble CSP antigen. RTS,S-mediated protective immunity was associated with a threshold of major repeat antibody titer. Combined titration of the antigen and adjuvant showed that reducing the adjuvant could improve antibody boosting post-3rd vaccination and reduce the threshold antibody concentration required for protection. Mouse models can provide a pathway for preclinical assessment of strategies to improve CSP vaccines against malaria.
Collapse
Affiliation(s)
- Christopher J Genito
- Structural Vaccinology Laboratory, Biologics Research and Development Branch, Walter Reed Army Institute of Research, Silver Spring, MD, 20910, USA
| | - Katherine Brooks
- Structural Vaccinology Laboratory, Biologics Research and Development Branch, Walter Reed Army Institute of Research, Silver Spring, MD, 20910, USA
| | - Alexis Smith
- Structural Vaccinology Laboratory, Biologics Research and Development Branch, Walter Reed Army Institute of Research, Silver Spring, MD, 20910, USA
| | - Emma Ryan
- Structural Vaccinology Laboratory, Biologics Research and Development Branch, Walter Reed Army Institute of Research, Silver Spring, MD, 20910, USA
| | - Kim Soto
- Structural Vaccinology Laboratory, Biologics Research and Development Branch, Walter Reed Army Institute of Research, Silver Spring, MD, 20910, USA
| | - Yuanzhang Li
- Center for Enabling Capabilities, Walter Reed Army Institute of Research, Silver Spring, MD, 20910, USA
| | | | - Sheetij Dutta
- Structural Vaccinology Laboratory, Biologics Research and Development Branch, Walter Reed Army Institute of Research, Silver Spring, MD, 20910, USA.
| |
Collapse
|
4
|
Valenciano AL, Gomez-Lorenzo MG, Vega-Rodríguez J, Adams JH, Roth A. In vitro models for human malaria: targeting the liver stage. Trends Parasitol 2022; 38:758-774. [PMID: 35780012 PMCID: PMC9378454 DOI: 10.1016/j.pt.2022.05.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 05/27/2022] [Accepted: 05/27/2022] [Indexed: 11/16/2022]
Abstract
The Plasmodium liver stage represents a vulnerable therapeutic target to prevent disease progression as the parasite resides in the liver before clinical representation caused by intraerythrocytic development. However, most antimalarial drugs target the blood stage of the parasite's life cycle, and the few drugs that target the liver stage are lethal to patients with a glucose-6-phosphate dehydrogenase deficiency. Furthermore, implementation of in vitro liver models to study and develop novel therapeutics against the liver stage of human Plasmodium species remains challenging. In this review, we focus on the progression of in vitro liver models developed for human Plasmodium spp. parasites, provide a brief review on important assay requirements, and lastly present recommendations to improve models to enhance the discovery process of novel preclinical therapeutics.
Collapse
Affiliation(s)
- Ana Lisa Valenciano
- Center for Global Health and Infectious Diseases, College of Public Health, University of South Florida, Tampa, FL 33612, USA; Global Health Medicines R&D, GlaxoSmithKline, Severo Ochoa 2, Tres Cantos 28760, Madrid, Spain
| | - Maria G Gomez-Lorenzo
- Global Health Medicines R&D, GlaxoSmithKline, Severo Ochoa 2, Tres Cantos 28760, Madrid, Spain
| | - Joel Vega-Rodríguez
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - John H Adams
- Center for Global Health and Infectious Diseases, College of Public Health, University of South Florida, Tampa, FL 33612, USA
| | - Alison Roth
- Department of Drug Discovery, Experimental Therapeutics Branch, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA.
| |
Collapse
|
5
|
Hutter JN, Robben PM, Lee C, Hamer M, Moon JE, Merino K, Zhu L, Galli H, Quinn X, Brown DR, Duncan E, Bolton J, Zou X, Angov E, Lanar DE, Rao M, Matyas GR, Beck Z, Bergmann-Leitner E, Soisson LA, Waters NC, Ngauy V, Regules J, Dutta S. First-in-human assessment of safety and immunogenicity of low and high doses of Plasmodium falciparum malaria protein 013 (FMP013) administered intramuscularly with ALFQ adjuvant in healthy malaria-naïve adults. Vaccine 2022; 40:5781-5790. [PMID: 36055874 DOI: 10.1016/j.vaccine.2022.08.048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Revised: 07/19/2022] [Accepted: 08/20/2022] [Indexed: 11/30/2022]
Abstract
The global burden of malaria remains substantial. Circumsporozoite protein (CSP) has been demonstrated to be an effective target antigen, however, improvements that offer more efficacious and more durable protection are still needed. In support of research and development of next-generation malaria vaccines, Walter Reed Army Institute of Research (WRAIR) has developed a CSP-based antigen (FMP013) and a novel adjuvant ALFQ (Army Liposome Formulation containing QS-21). We present a single center, open-label, dose-escalation Phase 1 clinical trial to evaluate the safety and immunogenicity of the FMP013/ALFQ malaria vaccine candidate. In this first-in-human evaluation of both the antigen and adjuvant, we enrolled ten subjects; five received 20 μg FMP013 / 0.5 mL ALFQ (Low dose group), and five received 40 μg FMP013 / 1.0 mL ALFQ (High dose group) on study days 1, 29, and 57. Adverse events and immune responses were assessed during the study period. The clinical safety profile was acceptable and there were no serious adverse events. Both groups exhibited robust humoral and cellular immunological responses, and compared favorably with historical responses reported for RTS,S/AS01. Based on a lower reactogenicity profile, the 20 μg FMP013 / 0.5 mL ALFQ (Low dose) was selected for follow-on efficacy testing by controlled human malaria infection (CHMI) with a separate cohort. Trial Registration:Clinicaltrials.gov Identifier NCT04268420 (Registered February 13, 2020).
Collapse
Affiliation(s)
- Jack N Hutter
- Walter Reed Army Institute of Research, Silver Spring, MD, United States.
| | - Paul M Robben
- Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Christine Lee
- Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Melinda Hamer
- Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - James E Moon
- Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Kristen Merino
- Walter Reed Army Institute of Research, Silver Spring, MD, United States; Current Affiliation: Division of Immunology, Tulane National Primate Research Center Covington, LA, United States
| | - Lei Zhu
- Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Heather Galli
- Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Xiaofei Quinn
- Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Dallas R Brown
- Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Elizabeth Duncan
- Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Jessica Bolton
- Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Xiaoyan Zou
- Navy Medical Research Center, Silver Spring, United States
| | - Evelina Angov
- Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - David E Lanar
- Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Mangala Rao
- Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Gary R Matyas
- Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Zoltan Beck
- Walter Reed Army Institute of Research, Silver Spring, MD, United States; Henry Jackson Foundation for Advancement of Military Medicine, Bethesda, MD. Present Address: Pfizer, Inc., 401 N Middletown Rd, Pearl River, New York 10965, United States
| | | | - Lorraine A Soisson
- United States Agency for International Development Malaria Vaccine Development Program, Washington DC, United States
| | - Norman C Waters
- Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Viseth Ngauy
- Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Jason Regules
- Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Sheetij Dutta
- Walter Reed Army Institute of Research, Silver Spring, MD, United States.
| |
Collapse
|
6
|
Schneider CG, Fey J, Zou X, Gerbasi V, Savransky T, Batt C, Bergmann-Leitner E, Angov E. Norovirus-VLPs expressing pre-erythrocytic malaria antigens induce functional immunity against sporozoite infection. Vaccine 2022; 40:4270-4280. [PMID: 35697572 DOI: 10.1016/j.vaccine.2022.05.076] [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: 03/22/2022] [Revised: 04/27/2022] [Accepted: 05/24/2022] [Indexed: 10/18/2022]
Abstract
Despite the development of prophylactic anti-malarial drugs and practices to prevent infection, malaria remains a health concern. Preclinical testing of novel malaria vaccine strategies achieved through rational antigen selection and novel particle-based delivery platforms is yielding encouraging results. One such platform, self-assembling virus-like particles (VLP) is safer than attenuated live viruses, and has been approved as a vaccination tool by the FDA. We explore the use of Norovirus sub-viral particles lacking the natural shell (S) domain forming the interior shell but that retain the protruding (P) structures of the native virus as a vaccine vector. Epitope selection and their surface display has the potential to focus antigen specific immune responses to crucial epitopes. Recombinant P-particles displaying epitopes from two malaria antigens, Plasmodium falciparum (Pf) CelTOS and Plasmodium falciparum (Pf) CSP, were evaluated for immunogenicity and their ability to confer protection in a murine challenge model. Immune responses induced in mice resulted either in sterile protection (displaying PfCelTOS epitopes) or in antibodies with functional activity against sporozoites (displaying PfCSP epitopes) in an in vitro liver-stage development assay (ILSDA). These results are encouraging and support further evaluation of this platform as a vaccine delivery system.
Collapse
Affiliation(s)
- Cosette G Schneider
- Malaria Biologics Branch, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA; Oak Ridge Institute for Science and Education, Oak Ridge, TN 37831, USA.
| | - Julien Fey
- Agave BioSystems, Ithaca, NY 14850, USA.
| | - Xiaoyan Zou
- Naval Medical Research Center, Silver Spring, MD 20910, USA; Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD 20817, USA
| | - Vince Gerbasi
- Naval Medical Research Center, Silver Spring, MD 20910, USA.
| | - Tatyana Savransky
- Entomology Branch, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA; General Dynamics Information Technology, Falls Church, VA 22042, USA.
| | - Carl Batt
- College of Agriculture and Life Sciences, Cornell University, Ithaca, NY 14853, USA.
| | - Elke Bergmann-Leitner
- Malaria Biologics Branch, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA.
| | - Evelina Angov
- Malaria Biologics Branch, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA.
| |
Collapse
|
7
|
Langowski MD, Khan FA, Savransky S, Brown DR, Balasubramaniyam A, Harrison WB, Zou X, Beck Z, Matyas GR, Regules JA, Miller R, Soisson LA, Batchelor AH, Dutta S. Restricted valency (NPNA) n repeats and junctional epitope-based circumsporozoite protein vaccines against Plasmodium falciparum. NPJ Vaccines 2022; 7:13. [PMID: 35087099 PMCID: PMC8795123 DOI: 10.1038/s41541-022-00430-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 12/14/2021] [Indexed: 12/02/2022] Open
Abstract
The Circumsporozoite Protein (CSP) of Plasmodium falciparum contains an N-terminal region, a conserved Region I (RI), a junctional region, 25-42 copies of major (NPNA) and minor repeats followed by a C-terminal domain. The recently approved malaria vaccine, RTS,S/AS01 contains NPNAx19 and the C-terminal region of CSP. The efficacy of RTS,S against natural infection is low and short-lived, and mapping epitopes of inhibitory monoclonal antibodies may allow for rational improvement of CSP vaccines. Tobacco Mosaic Virus (TMV) was used here to display the junctional epitope (mAb CIS43), Region I (mAb 5D5), NPNAx5, and NPNAx20 epitope of CSP (mAbs 317 and 580). Protection studies in mice revealed that Region I did not elicit protective antibodies, and polyclonal antibodies against the junctional epitope showed equivalent protection to NPNAx5. Combining the junctional and NPNAx5 epitopes reduced immunogenicity and efficacy, and increasing the repeat valency to NPNAx20 did not improve upon NPNAx5. TMV was confirmed as a versatile vaccine platform for displaying small epitopes defined by neutralizing mAbs. We show that polyclonal antibodies against engineered VLPs can recapitulate the binding specificity of the mAbs and immune-focusing by reducing the structural complexity of an epitope may be superior to immune-broadening as a vaccine design approach. Most importantly the junctional and restricted valency NPNA epitopes can be the basis for developing highly effective second-generation malaria vaccine candidates.
Collapse
Affiliation(s)
- Mark D Langowski
- Structural Vaccinology Lab, Malaria Biologics Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Farhat A Khan
- Structural Vaccinology Lab, Malaria Biologics Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Sofya Savransky
- Structural Vaccinology Lab, Malaria Biologics Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Dallas R Brown
- Structural Vaccinology Lab, Malaria Biologics Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Arasu Balasubramaniyam
- Structural Vaccinology Lab, Malaria Biologics Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - William B Harrison
- Structural Vaccinology Lab, Malaria Biologics Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Xiaoyan Zou
- Malaria Department, Naval Medical Research Center, Silver Spring, MD, USA
| | - Zoltan Beck
- US Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, USA
- Pfizer, 401N Middletown Rd, Pearl River, NY, 10965, USA
| | - Gary R Matyas
- US Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Jason A Regules
- Malaria Biologics Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Robin Miller
- United States Agency for International Development, Washington, DC, USA
| | | | - Adrian H Batchelor
- Structural Vaccinology Lab, Malaria Biologics Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Sheetij Dutta
- Structural Vaccinology Lab, Malaria Biologics Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA.
| |
Collapse
|
8
|
Blight J, Sala KA, Atcheson E, Kramer H, El-Turabi A, Real E, Dahalan FA, Bettencourt P, Dickinson-Craig E, Alves E, Salman AM, Janse CJ, Ashcroft FM, Hill AV, Reyes-Sandoval A, Blagborough AM, Baum J. Dissection-independent production of Plasmodium sporozoites from whole mosquitoes. Life Sci Alliance 2021; 4:e202101094. [PMID: 34135099 PMCID: PMC8321652 DOI: 10.26508/lsa.202101094] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 05/24/2021] [Accepted: 05/25/2021] [Indexed: 01/05/2023] Open
Abstract
Progress towards a protective vaccine against malaria remains slow. To date, only limited protection has been routinely achieved following immunisation with either whole-parasite (sporozoite) or subunit-based vaccines. One major roadblock to vaccine progress, and to pre-erythrocytic parasite biology in general, is the continued reliance on manual salivary gland dissection for sporozoite isolation from infected mosquitoes. Here, we report development of a multi-step method, based on batch processing of homogenised whole mosquitoes, slurry, and density-gradient filtration, which combined with free-flow electrophoresis rapidly produces a pure, infective sporozoite inoculum. Human-infective Plasmodium falciparum and rodent-infective Plasmodium berghei sporozoites produced in this way are two- to threefold more infective than salivary gland dissection sporozoites in in vitro hepatocyte infection assays. In an in vivo rodent malaria model, the same P. berghei sporozoites confer sterile protection from mosquito-bite challenge when immunisation is delivered intravenously or 60-70% protection when delivered intramuscularly. By improving purity, infectivity, and immunogenicity, this method represents a key advancement in capacity to produce research-grade sporozoites, which should impact delivery of a whole-parasite based malaria vaccine at scale in the future.
Collapse
Affiliation(s)
- Joshua Blight
- Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, London, UK
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Katarzyna A Sala
- Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, London, UK
| | - Erwan Atcheson
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Holger Kramer
- Department of Physiology, Anatomy and Genetics, Henry Wellcome Building for Gene Function, University of Oxford, Oxford, UK
- Medical Research Council London Institute of Medical Sciences, Imperial College London, Hammersmith Hospital, London, UK
| | - Aadil El-Turabi
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Eliana Real
- Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, London, UK
| | - Farah A Dahalan
- Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, London, UK
| | - Paulo Bettencourt
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Emma Dickinson-Craig
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Eduardo Alves
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Ahmed M Salman
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Chris J Janse
- Department of Parasitology, Leiden Malaria Research Group, Center of Infectious Diseases, Leiden University Medical Center, (LUMC, L4-Q), Leiden, The Netherlands
| | - Frances M Ashcroft
- Department of Physiology, Anatomy and Genetics, Henry Wellcome Building for Gene Function, University of Oxford, Oxford, UK
| | - Adrian Vs Hill
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Arturo Reyes-Sandoval
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
- Instituto Politécnico Nacional, Mexico City, Mexico
| | - Andrew M Blagborough
- Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, London, UK
- Department of Pathology, University of Cambridge, Cambridge, UK
| | - Jake Baum
- Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, London, UK
| |
Collapse
|
9
|
Mallory KL, Taylor JA, Zou X, Waghela IN, Schneider CG, Sibilo MQ, Punde NM, Perazzo LC, Savransky T, Sedegah M, Dutta S, Janse CJ, Pardi N, Lin PJC, Tam YK, Weissman D, Angov E. Messenger RNA expressing PfCSP induces functional, protective immune responses against malaria in mice. NPJ Vaccines 2021; 6:84. [PMID: 34145286 PMCID: PMC8213722 DOI: 10.1038/s41541-021-00345-0] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 05/24/2021] [Indexed: 02/05/2023] Open
Abstract
Human malaria affects the vast majority of the world's population with the Plasmodium falciparum species causing the highest rates of morbidity and mortality. With no licensed vaccine and leading candidates achieving suboptimal protection in the field, the need for an effective immunoprophylactic option continues to motivate the malaria research community to explore alternative technologies. Recent advances in the mRNA discipline have elevated the long-neglected platform to the forefront of infectious disease research. As the immunodominant coat protein of the invasive stage of the malaria parasite, circumsporozoite protein (PfCSP) was selected as the antigen of choice to assess the immunogenic and protective potential of an mRNA malaria vaccine. In mammalian cell transfection experiments, PfCSP mRNA was well expressed and cell associated. In the transition to an in vivo murine model, lipid nanoparticle (LNP) encapsulation was applied to protect and deliver the mRNA to the cell translation machinery and supply adjuvant activity. The immunogenic effect of an array of factors was explored, such as formulation, dose, number, and interval of immunizations. PfCSP mRNA-LNP achieved sterile protection against infection with two P. berghei PfCSP transgenic parasite strains, with mRNA dose and vaccination interval having a greater effect on outcome. This investigation serves as the assessment of pre-erythrocytic malaria, PfCSP mRNA vaccine candidate resulting in sterile protection, with numerous factors affecting protective efficacy, making it a compelling candidate for further investigation.
Collapse
Affiliation(s)
- Katherine L Mallory
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
- Parsons Corporation, Centreville, VA, USA
| | - Justin A Taylor
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
- The Geneva Foundation, Tacoma, WA, USA
| | - Xiaoyan Zou
- Naval Medical Research Center, Silver Spring, MD, USA
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Ishita N Waghela
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
- Parsons Corporation, Centreville, VA, USA
| | - Cosette G Schneider
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
- Oak Ridge Institute for Science and Education, Oak Ridge, TN, USA
| | - Michael Q Sibilo
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
- Parsons Corporation, Centreville, VA, USA
| | - Neeraja M Punde
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
- The Geneva Foundation, Tacoma, WA, USA
| | - Leah C Perazzo
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
- General Dynamics Information Technology, Falls Church, VA, USA
| | - Tatyana Savransky
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
- General Dynamics Information Technology, Falls Church, VA, USA
| | | | - Sheetij Dutta
- Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Chris J Janse
- Leiden University Medical Center, Leiden, the Netherlands
| | | | | | - Ying K Tam
- Acuitas Therapeutics, Vancouver, BC, Canada
| | | | - Evelina Angov
- Walter Reed Army Institute of Research, Silver Spring, MD, USA.
| |
Collapse
|
10
|
Kulkeaw K. Next-Generation Human Liver Models for Antimalarial Drug Assays. Antibiotics (Basel) 2021; 10:antibiotics10060642. [PMID: 34071885 PMCID: PMC8229011 DOI: 10.3390/antibiotics10060642] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 05/26/2021] [Accepted: 05/26/2021] [Indexed: 12/23/2022] Open
Abstract
Advances in malaria prevention and treatment have significantly reduced the related morbidity and mortality worldwide, however, malaria continues to be a major threat to global public health. Because Plasmodium parasites reside in the liver prior to the appearance of clinical manifestations caused by intraerythrocytic development, the Plasmodium liver stage represents a vulnerable therapeutic target to prevent progression. Currently, a small number of drugs targeting liver-stage parasites are available, but all cause lethal side effects in glucose-6-phosphate dehydrogenase-deficient individuals, emphasizing the necessity for new drug development. Nevertheless, a longstanding hurdle to developing new drugs is the availability of appropriate in vitro cultures, the crucial conventional platform for evaluating the efficacy and toxicity of drugs in the preclinical phase. Most current cell culture systems rely primarily on growing immortalized or cancerous cells in the form of a two-dimensional monolayer, which is not very physiologically relevant to the complex cellular architecture of the human body. Although primary human cells are more relevant to human physiology, they are mainly hindered by batch-to-batch variation, limited supplies, and ethical issues. Advances in stem cell technologies and multidimensional culture have allowed the modelling of human infectious diseases. Here, current in vitro hepatic models and toolboxes for assaying the antimalarial drug activity are summarized. Given the physiological potential of pluripotent and adult stem cells to model liver-stage malaria, the opportunities and challenges in drug development against liver-stage malaria is highlighted, paving the way to assess the efficacy of hepatic plasmodicidal activity.
Collapse
Affiliation(s)
- Kasem Kulkeaw
- Department of Parasitology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| |
Collapse
|
11
|
In vitro and in vivo inhibition of malaria parasite infection by monoclonal antibodies against Plasmodium falciparum circumsporozoite protein (CSP). Sci Rep 2021; 11:5318. [PMID: 33674699 PMCID: PMC7970865 DOI: 10.1038/s41598-021-84622-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 02/11/2021] [Indexed: 01/23/2023] Open
Abstract
Plasmodium falciparum malaria contributes to a significant global disease burden. Circumsporozoite protein (CSP), the most abundant sporozoite stage antigen, is a prime vaccine candidate. Inhibitory monoclonal antibodies (mAbs) against CSP map to either a short junctional sequence or the central (NPNA)n repeat region. We compared in vitro and in vivo activities of six CSP-specific mAbs derived from human recipients of a recombinant CSP vaccine RTS,S/AS01 (mAbs 317 and 311); an irradiated whole sporozoite vaccine PfSPZ (mAbs CIS43 and MGG4); or individuals exposed to malaria (mAbs 580 and 663). RTS,S mAb 317 that specifically binds the (NPNA)n epitope, had the highest affinity and it elicited the best sterile protection in mice. The most potent inhibitor of sporozoite invasion in vitro was mAb CIS43 which shows dual-specific binding to the junctional sequence and (NPNA)n. In vivo mouse protection was associated with the mAb reactivity to the NANPx6 peptide, the in vitro inhibition of sporozoite invasion activity, and kinetic parameters measured using intact mAbs or their Fab fragments. Buried surface area between mAb and its target epitope was also associated with in vivo protection. Association and disconnects between in vitro and in vivo readouts has important implications for the design and down-selection of the next generation of CSP based interventions.
Collapse
|
12
|
Abstract
Introduction: An effective vaccine against malaria forms a global health priority. Both naturally acquired immunity and sterile protection induced by irradiated sporozoite immunization were described decades ago. Still no vaccine exists that sufficiently protects children in endemic areas. Identifying immunological correlates of vaccine efficacy can inform rational vaccine design and potentially accelerate clinical development.Areas covered: We discuss recent research on immunological correlates of malaria vaccine efficacy, including: insights from state-of-the-art omics platforms and systems vaccinology analyses; functional anti-parasitic assays; pre-immunization predictors of vaccine efficacy; and comparison of correlates of vaccine efficacy against controlled human malaria infections (CHMI) and against naturally acquired infections.Expert Opinion: Effective vaccination may be achievable without necessarily understanding immunological correlates, but the relatively disappointing efficacy of malaria vaccine candidates in target populations is concerning. Hypothesis-generating omics and systems vaccinology analyses, alongside assessment of pre-immunization correlates, have the potential to bring about paradigm-shifts in malaria vaccinology. Functional assays may represent in vivo effector mechanisms, but have scarcely been formally assessed as correlates. Crucially, evidence is still meager that correlates of vaccine efficacy against CHMI correspond with those against naturally acquired infections in target populations. Finally, the diversity of immunological assays and efficacy endpoints across malaria vaccine trials remains a major confounder.
Collapse
Affiliation(s)
| | - Matthew B B McCall
- Department of Medical Microbiology, Radboud University Medical Centre, Nijmegen, The Netherlands.,Institut für Tropenmedizin, Universitätsklinikum Tübingen, Tübingen, Germany.,Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
| |
Collapse
|
13
|
Skwarczynski M, Chandrudu S, Rigau-Planella B, Islam MT, Cheong YS, Liu G, Wang X, Toth I, Hussein WM. Progress in the Development of Subunit Vaccines against Malaria. Vaccines (Basel) 2020; 8:vaccines8030373. [PMID: 32664421 PMCID: PMC7563759 DOI: 10.3390/vaccines8030373] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 07/06/2020] [Accepted: 07/07/2020] [Indexed: 12/02/2022] Open
Abstract
Malaria is a life-threatening disease and one of the main causes of morbidity and mortality in the human population. The disease also results in a major socio-economic burden. The rapid spread of malaria epidemics in developing countries is exacerbated by the rise in drug-resistant parasites and insecticide-resistant mosquitoes. At present, malaria research is focused mainly on the development of drugs with increased therapeutic effects against Plasmodium parasites. However, a vaccine against the disease is preferable over treatment to achieve long-term control. Trials to develop a safe and effective immunization protocol for the control of malaria have been occurring for decades, and continue on today; still, no effective vaccines are available on the market. Recently, peptide-based vaccines have become an attractive alternative approach. These vaccines utilize short protein fragments to induce immune responses against malaria parasites. Peptide-based vaccines are safer than traditional vaccines, relatively inexpensive to produce, and can be composed of multiple T- and B-cell epitopes integrated into one antigenic formulation. Various combinations, based on antigen choice, peptide epitope modification and delivery mechanism, have resulted in numerous potential malaria vaccines candidates; these are presently being studied in both preclinical and clinical trials. This review describes the current landscape of peptide-based vaccines, and addresses obstacles and opportunities in the production of malaria vaccines.
Collapse
Affiliation(s)
- Mariusz Skwarczynski
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia; (M.S.); (S.C.); (B.R.-P.); (M.T.I.); (Y.S.C.); (G.L.); (X.W.)
| | - Saranya Chandrudu
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia; (M.S.); (S.C.); (B.R.-P.); (M.T.I.); (Y.S.C.); (G.L.); (X.W.)
| | - Berta Rigau-Planella
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia; (M.S.); (S.C.); (B.R.-P.); (M.T.I.); (Y.S.C.); (G.L.); (X.W.)
| | - Md. Tanjir Islam
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia; (M.S.); (S.C.); (B.R.-P.); (M.T.I.); (Y.S.C.); (G.L.); (X.W.)
| | - Yee S. Cheong
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia; (M.S.); (S.C.); (B.R.-P.); (M.T.I.); (Y.S.C.); (G.L.); (X.W.)
| | - Genan Liu
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia; (M.S.); (S.C.); (B.R.-P.); (M.T.I.); (Y.S.C.); (G.L.); (X.W.)
| | - Xiumin Wang
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia; (M.S.); (S.C.); (B.R.-P.); (M.T.I.); (Y.S.C.); (G.L.); (X.W.)
- Gene Engineering Laboratory, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
- Key Laboratory of Feed Biotechnology, Ministry of Agriculture and Rural Affairs, Beijing 100081, China
| | - Istvan Toth
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia; (M.S.); (S.C.); (B.R.-P.); (M.T.I.); (Y.S.C.); (G.L.); (X.W.)
- School of Pharmacy, Pharmacy Australia Centre of Excellence, The University of Queensland, Woolloongabba, QLD 4072, Australia
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, QLD 4072, Australia
- Correspondence: (I.T.); (W.M.H.)
| | - Waleed M. Hussein
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia; (M.S.); (S.C.); (B.R.-P.); (M.T.I.); (Y.S.C.); (G.L.); (X.W.)
- Correspondence: (I.T.); (W.M.H.)
| |
Collapse
|
14
|
Optimization of a Plasmodium falciparum circumsporozoite protein repeat vaccine using the tobacco mosaic virus platform. Proc Natl Acad Sci U S A 2020; 117:3114-3122. [PMID: 31988134 PMCID: PMC7022184 DOI: 10.1073/pnas.1911792117] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
RTS,S/AS01 is a circumsporozoite protein (CSP)-based malaria vaccine that confers partial protection against malaria in endemic areas. Recent reports have elucidated structures of monoclonal antibodies that bind to the central (NPNA) repeat region of CSP and that inhibit parasite invasion. Antigen configuration and copy number of CSP repeats displayed on a tobacco mosaic virus (TMV) particle platform were studied. A TMV vaccine containing CSP repeats displayed as a loop induced 10× better antibody titer than a nearly full-length CSP in mice. In rhesus model, this translated to a 5× improvement in titer. Rhesus antibodies potently inhibited parasite invasion up to 11 mo after vaccination. An optimized epitope-focused, repeat-only CSP vaccine may be sufficient or better than the existing CSP vaccines. Plasmodium falciparum vaccine RTS,S/AS01 is based on the major NPNA repeat and the C-terminal region of the circumsporozoite protein (CSP). RTS,S-induced NPNA-specific antibody titer and avidity have been associated with high-level protection in naïve subjects, but efficacy and longevity in target populations is relatively low. In an effort to improve upon RTS,S, a minimal repeat-only, epitope-focused, protective, malaria vaccine was designed. Repeat antigen copy number and flexibility was optimized using the tobacco mosaic virus (TMV) display platform. Comparing antigenicity of TMV displaying 3 to 20 copies of NPNA revealed that low copy number can reduce the abundance of low-affinity monoclonal antibody (mAb) epitopes while retaining high-affinity mAb epitopes. TMV presentation improved titer and avidity of repeat-specific Abs compared to a nearly full-length protein vaccine (FL-CSP). NPNAx5 antigen displayed as a loop on the TMV particle was found to be most optimal and its efficacy could be further augmented by combination with a human-use adjuvant ALFQ that contains immune-stimulators. These data were confirmed in rhesus macaques where a low dose of TMV-NPNAx5 elicited Abs that persisted at functional levels for up to 11 mo. We show here a complex association between NPNA copy number, flexibility, antigenicity, immunogenicity, and efficacy of CSP-based vaccines. We hypothesize that designing minimal epitope CSP vaccines could confer better and more durable protection against malaria. Preclinical data presented here supports the evaluation of TMV-NPNAx5/ALFQ in human trials.
Collapse
|
15
|
Winer B, Edgel KA, Zou X, Sellau J, Hadiwidjojo S, Garver LS, McDonough CE, Kelleher NL, Thomas PM, Villasante E, Ploss A, Gerbasi VR. Identification of Plasmodium falciparum proteoforms from liver stage models. Malar J 2020; 19:10. [PMID: 31910830 PMCID: PMC6947969 DOI: 10.1186/s12936-019-3093-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 12/26/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Immunization with attenuated malaria sporozoites protects humans from experimental malaria challenge by mosquito bite. Protection in humans is strongly correlated with the production of T cells targeting a heterogeneous population of pre-erythrocyte antigen proteoforms, including liver stage antigens. Currently, few T cell epitopes derived from Plasmodium falciparum, the major aetiologic agent of malaria in humans are known. METHODS In this study both in vitro and in vivo malaria liver stage models were used to sequence host and pathogen proteoforms. Proteoforms from these diverse models were subjected to mild acid elution (of soluble forms), multi-dimensional fractionation, tandem mass spectrometry, and top-down bioinformatics analysis to identify proteoforms in their intact state. RESULTS These results identify a group of host and malaria liver stage proteoforms that meet a 5% false discovery rate threshold. CONCLUSIONS This work provides proof-of-concept for the validity of this mass spectrometry/bioinformatic approach for future studies seeking to reveal malaria liver stage antigens towards vaccine development.
Collapse
Affiliation(s)
- Benjamin Winer
- Department of Molecular Biology, Princeton University, Washington Road, Princeton, NJ, 08544, USA
| | - Kimberly A Edgel
- Naval Medical Research Center, 503 Robert Grant Avenue, Silver Spring, MD, 20910, USA
| | - Xiaoyan Zou
- Naval Medical Research Center, 503 Robert Grant Avenue, Silver Spring, MD, 20910, USA.,The Henry M Jackson Foundation, 6720A Rockledge Dr., Rockville, MD, 20817, USA
| | - Julie Sellau
- Department of Molecular Biology, Princeton University, Washington Road, Princeton, NJ, 08544, USA.,Department of Molecular Biology and Immunology, Molecular Infection Immunology, Bernhard Nocht Institute for Tropical Medicine, Bernhard-Nocht-Straße 74, 20359, Hamburg, Germany
| | - Sri Hadiwidjojo
- Naval Medical Research Center, 503 Robert Grant Avenue, Silver Spring, MD, 20910, USA.,The Henry M Jackson Foundation, 6720A Rockledge Dr., Rockville, MD, 20817, USA
| | - Lindsey S Garver
- Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD, 20190, USA
| | | | - Neil L Kelleher
- Northwestern University National Resource for Translational Proteomics, Evanston, IL, 60208, USA
| | - Paul M Thomas
- Northwestern University National Resource for Translational Proteomics, Evanston, IL, 60208, USA
| | - Eileen Villasante
- Naval Medical Research Center, 503 Robert Grant Avenue, Silver Spring, MD, 20910, USA
| | - Alexander Ploss
- Department of Molecular Biology, Princeton University, Washington Road, Princeton, NJ, 08544, USA.
| | - Vincent R Gerbasi
- Naval Medical Research Center, 503 Robert Grant Avenue, Silver Spring, MD, 20910, USA. .,Northwestern University National Resource for Translational Proteomics, Evanston, IL, 60208, USA.
| |
Collapse
|
16
|
Goh YS, McGuire D, Rénia L. Vaccination With Sporozoites: Models and Correlates of Protection. Front Immunol 2019; 10:1227. [PMID: 31231377 PMCID: PMC6560154 DOI: 10.3389/fimmu.2019.01227] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 05/14/2019] [Indexed: 12/14/2022] Open
Abstract
Despite continuous efforts, the century-old goal of eradicating malaria still remains. Multiple control interventions need to be in place simultaneously to achieve this goal. In addition to effective control measures, drug therapies and insecticides, vaccines are critical to reduce mortality and morbidity. Hence, there are numerous studies investigating various malaria vaccine candidates. Most of the malaria vaccine candidates are subunit vaccines. However, they have shown limited efficacy in Phase II and III studies. To date, only whole parasite formulations have been shown to induce sterile immunity in human. In this article, we review and discuss the recent developments in vaccination with sporozoites and the mechanisms of protection involved.
Collapse
Affiliation(s)
- Yun Shan Goh
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (ASTAR), Biopolis, Singapore, Singapore
| | - Daniel McGuire
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (ASTAR), Biopolis, Singapore, Singapore.,School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Laurent Rénia
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (ASTAR), Biopolis, Singapore, Singapore.,School of Biological Sciences, Nanyang Technological University, Singapore, Singapore.,Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| |
Collapse
|
17
|
Cawlfield A, Genito CJ, Beck Z, Bergmann-Leitner ES, Bitzer AA, Soto K, Zou X, Hadiwidjojo SH, Gerbasi RV, Mullins AB, Noe A, Waters NC, Alving CR, Matyas GR, Dutta S. Safety, toxicity and immunogenicity of a malaria vaccine based on the circumsporozoite protein (FMP013) with the adjuvant army liposome formulation containing QS21 (ALFQ). Vaccine 2019; 37:3793-3803. [PMID: 31151801 DOI: 10.1016/j.vaccine.2019.05.059] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Revised: 05/16/2019] [Accepted: 05/20/2019] [Indexed: 01/21/2023]
Abstract
Antibodies to Circumsporozoite protein (CSP) confer protection against controlled human malaria infection (CHMI) caused by the parasite Plasmodium falciparum. Although CSP is highly immunogenic, it does not induce long lasting protection and efforts to improve CSP-specific immunological memory and duration of protection are underway. We have previously reported that the clinical grade CSP vaccine FMP013 was immunogenic and protective against malaria challenge in mice when combined with the Army Liposomal Formulation adjuvant containing immune modulators 3D-PHAD™ and QS21 (ALFQ). To move forward with clinical evaluation, we now report the safety, toxicity and immunogenicity of clinical grade FMP013 and ALFQ in Rhesus macaques. Three groups of Rhesus (n = 6) received half or full human dose of FMP013 + ALFQ on a 0-1-2 month schedule, which showed mild local site reactions with no hematologic derangements in red blood cell homeostasis, liver function or kidney function. Immunization induced a transient systemic inflammatory response, including elevated white blood cell counts, mild fever, and a few incidences of elevated creatine kinase, receding to normal range by day 7 post vaccination. Optimal immunogenicity in Rhesus was observed using a 1 mL ALFQ + 20 µg FMP013 dose. Doubling the FMP013 antigen dose to 40 µg had no effect while halving the ALFQ adjuvant dose to 0.5 mL lowered immunogenicity. Similar to data generated in mice, FMP013 + ALFQ induced serum antibodies that reacted to all regions of the CSP molecule and a Th1-biased cytokine response in Rhesus. Rhesus antibody response to FMP013 + ALFQ was found to be non-inferior to historical benchmarks including that of RTS,S + AS01 in humans. A four-dose GLP toxicity study in rabbits confirmed no local site reactions and transient systemic inflammation associated with ALFQ adjuvant administration. These safety and immunogenicity data support the clinical progression and testing of FMP013 + ALFQ in a CHMI trial in the near future.
Collapse
Affiliation(s)
- Alicia Cawlfield
- Department of Veterinary Medicine, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
| | - Christopher J Genito
- Structural Vaccinology Laboratory, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
| | - Zoltan Beck
- Military HIV Research Program, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA; Henry M. Jackson Foundation for the Advancement of Military Medicine, 6720A Rockledge Drive, Bethesda, MD 20817, USA
| | - Elke S Bergmann-Leitner
- Flow-cytometeric Center, Malaria Vaccine Branch, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
| | - Alexis A Bitzer
- Structural Vaccinology Laboratory, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
| | - Kimberly Soto
- Structural Vaccinology Laboratory, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
| | - Xiaoyan Zou
- Malaria Department, Naval Medical Research Center, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
| | - Sri H Hadiwidjojo
- Malaria Department, Naval Medical Research Center, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
| | - Robert V Gerbasi
- Malaria Department, Naval Medical Research Center, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
| | - Anna B Mullins
- Department of Veterinary Medicine, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
| | - Amy Noe
- Leidos Life Sciences, 5202 Presidents Court, Suite 110, Fredrick, MD 21703, USA
| | - Norman C Waters
- Malaria Vaccine Branch, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
| | - Carl R Alving
- Military HIV Research Program, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
| | - Gary R Matyas
- Military HIV Research Program, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA
| | - Sheetij Dutta
- Structural Vaccinology Laboratory, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA.
| |
Collapse
|
18
|
Critical examination of approaches exploited to assess the effectiveness of transmission-blocking drugs for malaria. Future Med Chem 2018; 10:2619-2639. [PMID: 30499742 DOI: 10.4155/fmc-2018-0169] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
In the absence of clinically proven vaccines and emerging resistance to common antimalarials and insecticides, the onus of interrupting the life cycle of Plasmodium falciparum, is upon the transmission-blocking drugs. Current transmission-blocking drug primaquine finds its use restricted because of associated hemolytic toxicity issues in Glucose-6-Phosphate-Dehydrogenase deficient individuals. This article provides an extensive review of the assays used by the investigators to evaluate the transmission-blocking activity of drugs. Furthermore, limitations in existing transmission-blocking assessment approaches/studies are also covered in detail. This review is expected to help in the identification of lacunae in current understanding of transmission-blocking strategies, which are hindering our efforts to develop sustainable and effective transmission-blocking interventions.
Collapse
|
19
|
Kupffer Cells Survive Plasmodium berghei Sporozoite Exposure and Respond with a Rapid Cytokine Release. Pathogens 2018; 7:pathogens7040091. [PMID: 30477234 PMCID: PMC6313776 DOI: 10.3390/pathogens7040091] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 11/20/2018] [Accepted: 11/21/2018] [Indexed: 01/08/2023] Open
Abstract
The liver stage of the Plasmodium life cycle features sporozoite traversal of the liver sinusoidal barrier through Kupffer cells (KCs) followed by invasion of hepatocytes. Little is known about the interaction of Plasmodium sporozoites with KCs, the liver-resident macrophages. Previous reports suggest KCs do not mount a pro-inflammatory response and undergo cell death following this interaction. Our work explores this interaction using primary rat KCs (PRKCs) and Plasmodium berghei sporozoites. We analyzed PRKC culture supernatants for markers of an immunological response through cytokine arrays. Additionally, cell wounding and death were assessed by monitoring lactate dehydrogenase (LDH) levels in these supernatants and by live/dead cell imaging. We found that PRKCs mount an immunological response to P. berghei sporozoites by releasing a diverse set of both pro- and anti-inflammatory cytokines, including IFNγ, IL-12p70, Mip-3α, IL-2, RANTES, IL-1α, IL-4, IL-5, IL-13, EPO, VEGF, IL-7, and IL-17α. We also observed no difference in LDH level or live/dead staining upon sporozoite exposure, suggesting that the KCs are not deeply wounded or dying. Overall, our data suggest that sporozoites may be actively modulating the KC's reaction to their presence and altering the way the innate immune system is triggered by KCs.
Collapse
|
20
|
Roth A, Maher SP, Conway AJ, Ubalee R, Chaumeau V, Andolina C, Kaba SA, Vantaux A, Bakowski MA, Thomson-Luque R, Adapa SR, Singh N, Barnes SJ, Cooper CA, Rouillier M, McNamara CW, Mikolajczak SA, Sather N, Witkowski B, Campo B, Kappe SHI, Lanar DE, Nosten F, Davidson S, Jiang RHY, Kyle DE, Adams JH. A comprehensive model for assessment of liver stage therapies targeting Plasmodium vivax and Plasmodium falciparum. Nat Commun 2018; 9:1837. [PMID: 29743474 PMCID: PMC5943321 DOI: 10.1038/s41467-018-04221-9] [Citation(s) in RCA: 101] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 04/10/2018] [Indexed: 12/26/2022] Open
Abstract
Malaria liver stages represent an ideal therapeutic target with a bottleneck in parasite load and reduced clinical symptoms; however, current in vitro pre-erythrocytic (PE) models for Plasmodium vivax and P. falciparum lack the efficiency necessary for rapid identification and effective evaluation of new vaccines and drugs, especially targeting late liver-stage development and hypnozoites. Herein we report the development of a 384-well plate culture system using commercially available materials, including cryopreserved primary human hepatocytes. Hepatocyte physiology is maintained for at least 30 days and supports development of P. vivax hypnozoites and complete maturation of P. vivax and P. falciparum schizonts. Our multimodal analysis in antimalarial therapeutic research identifies important PE inhibition mechanisms: immune antibodies against sporozoite surface proteins functionally inhibit liver stage development and ion homeostasis is essential for schizont and hypnozoite viability. This model can be implemented in laboratories in disease-endemic areas to accelerate vaccine and drug discovery research.
Collapse
Affiliation(s)
- Alison Roth
- Department of Global Health, College of Public Health, Center for Global Health and Infectious Diseases Research, University of South Florida, 3720 Spectrum Blvd 404, Tampa, FL, 33612, USA
| | - Steven P Maher
- Department of Global Health, College of Public Health, Center for Global Health and Infectious Diseases Research, University of South Florida, 3720 Spectrum Blvd 404, Tampa, FL, 33612, USA
- Center for Tropical and Emerging Global Diseases, University of Georgia, 500 DW Brooks Dr. Suite 370, Athens, GA, 30602, USA
| | - Amy J Conway
- Department of Global Health, College of Public Health, Center for Global Health and Infectious Diseases Research, University of South Florida, 3720 Spectrum Blvd 404, Tampa, FL, 33612, USA
| | - Ratawan Ubalee
- Department of Entomology, Armed Forces Research Institute of Medical Sciences (AFRIMS), 315/6 Rajvithi Rd, Bangkok, 10400, Thailand
| | - Victor Chaumeau
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Shoklo Malaria Research Unit, Mahidol Oxford Research Unit, Faculty of Tropical Medicine, Mahidol University, 68/30 Bantung Rd, Mae Sot, Tak, 63110, Thailand
| | - Chiara Andolina
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Shoklo Malaria Research Unit, Mahidol Oxford Research Unit, Faculty of Tropical Medicine, Mahidol University, 68/30 Bantung Rd, Mae Sot, Tak, 63110, Thailand
| | - Stephen A Kaba
- Malaria Vaccine Branch, Walter Reed Army Institute of Research, 503 Robert Grant Ave, Silver Spring, MD, 20910, USA
| | - Amélie Vantaux
- Malaria Molecular Epidemiology Unit, Institut Pasteur du Cambodge, 5 Boulevard Monivong-PO Box 983, Phnom Penh, 12 201, Cambodia
| | - Malina A Bakowski
- California Institute for Biomedical Research (Calibr), 11119N. Torrey Pines Rd, Suite 100, La Jolla, CA, 92037, USA
| | - Richard Thomson-Luque
- Department of Global Health, College of Public Health, Center for Global Health and Infectious Diseases Research, University of South Florida, 3720 Spectrum Blvd 404, Tampa, FL, 33612, USA
| | - Swamy Rakesh Adapa
- Department of Global Health, College of Public Health, Center for Global Health and Infectious Diseases Research, University of South Florida, 3720 Spectrum Blvd 404, Tampa, FL, 33612, USA
| | - Naresh Singh
- Department of Global Health, College of Public Health, Center for Global Health and Infectious Diseases Research, University of South Florida, 3720 Spectrum Blvd 404, Tampa, FL, 33612, USA
| | - Samantha J Barnes
- Department of Global Health, College of Public Health, Center for Global Health and Infectious Diseases Research, University of South Florida, 3720 Spectrum Blvd 404, Tampa, FL, 33612, USA
| | - Caitlin A Cooper
- Center for Tropical and Emerging Global Diseases, University of Georgia, 500 DW Brooks Dr. Suite 370, Athens, GA, 30602, USA
| | - Mélanie Rouillier
- Medicines for Malaria Venture, Pré-Bois Rd 20, Meyrin, 1215, Switzerland
| | - Case W McNamara
- California Institute for Biomedical Research (Calibr), 11119N. Torrey Pines Rd, Suite 100, La Jolla, CA, 92037, USA
| | - Sebastian A Mikolajczak
- Center for Infectious Disease Research, 307 Westlake Ave N Suite 500, Seattle, WA, 98109, USA
| | - Noah Sather
- Center for Infectious Disease Research, 307 Westlake Ave N Suite 500, Seattle, WA, 98109, USA
| | - Benoît Witkowski
- California Institute for Biomedical Research (Calibr), 11119N. Torrey Pines Rd, Suite 100, La Jolla, CA, 92037, USA
| | - Brice Campo
- Medicines for Malaria Venture, Pré-Bois Rd 20, Meyrin, 1215, Switzerland
| | - Stefan H I Kappe
- Center for Infectious Disease Research, 307 Westlake Ave N Suite 500, Seattle, WA, 98109, USA
| | - David E Lanar
- Malaria Vaccine Branch, Walter Reed Army Institute of Research, 503 Robert Grant Ave, Silver Spring, MD, 20910, USA
| | - François Nosten
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Shoklo Malaria Research Unit, Mahidol Oxford Research Unit, Faculty of Tropical Medicine, Mahidol University, 68/30 Bantung Rd, Mae Sot, Tak, 63110, Thailand
| | - Silas Davidson
- Department of Entomology, Armed Forces Research Institute of Medical Sciences (AFRIMS), 315/6 Rajvithi Rd, Bangkok, 10400, Thailand
| | - Rays H Y Jiang
- Department of Global Health, College of Public Health, Center for Global Health and Infectious Diseases Research, University of South Florida, 3720 Spectrum Blvd 404, Tampa, FL, 33612, USA
| | - Dennis E Kyle
- Department of Global Health, College of Public Health, Center for Global Health and Infectious Diseases Research, University of South Florida, 3720 Spectrum Blvd 404, Tampa, FL, 33612, USA
- Center for Tropical and Emerging Global Diseases, University of Georgia, 500 DW Brooks Dr. Suite 370, Athens, GA, 30602, USA
| | - John H Adams
- Department of Global Health, College of Public Health, Center for Global Health and Infectious Diseases Research, University of South Florida, 3720 Spectrum Blvd 404, Tampa, FL, 33612, USA.
| |
Collapse
|
21
|
Majji S, Wijayalath W, Shashikumar S, Brumeanu TD, Casares S. Humanized DRAGA mice immunized with Plasmodium falciparum sporozoites and chloroquine elicit protective pre-erythrocytic immunity. Malar J 2018. [PMID: 29540197 PMCID: PMC5853061 DOI: 10.1186/s12936-018-2264-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Background Human-immune-system humanized mouse models can bridge the gap between humans and conventional mice for testing human vaccines. The HLA-expressing humanized DRAGA (HLA-A2.HLA-DR4.Rag1KO.IL2RγcKO.NOD) mice reconstitute a functional human-immune-system and sustain the complete life cycle of Plasmodium falciparum. Herein, the DRAGA mice were investigated for immune responses following immunization with live P. falciparum sporozoites under chloroquine chemoprophylaxis (CPS-CQ), an immunization approach that showed in human trials to confer pre-erythrocytic immunity. Results The CPS-CQ immunized DRAGA mice (i) elicited human CD4 and CD8 T cell responses to antigens expressed by P. falciparum sporozoites (Pfspz) and by the infected-red blood cells (iRBC). The Pfspz-specific human T cell responses were found to be systemic (spleen and liver), whereas the iRBCs-specific human T cell responses were more localized to the liver, (ii) elicited stronger antibody responses to the Pfspz than to the iRBCs, and (iii) they were protected against challenge with infectious Pfspz but not against challenge with iRBCs. Conclusions The DRAGA mice represent a new pre-clinical model to investigate the immunogenicity and protective efficacy of P. falciparum malaria vaccine candidates. Electronic supplementary material The online version of this article (10.1186/s12936-018-2264-y) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Sai Majji
- US Military Malaria Vaccine Program, Naval Medical Research Center/Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Wathsala Wijayalath
- US Military Malaria Vaccine Program, Naval Medical Research Center/Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Soumya Shashikumar
- US Military Malaria Vaccine Program, Naval Medical Research Center/Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Teodor D Brumeanu
- Department of Medicine, Uniformed Services University of Health Sciences, Bethesda, MD, USA
| | - Sofia Casares
- US Military Malaria Vaccine Program, Naval Medical Research Center/Walter Reed Army Institute of Research, Silver Spring, MD, USA. .,Department of Medicine, Uniformed Services University of Health Sciences, Bethesda, MD, USA.
| |
Collapse
|
22
|
An Opsonic Phagocytosis Assay for Plasmodium falciparum Sporozoites. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2017; 24:CVI.00445-16. [PMID: 27881488 DOI: 10.1128/cvi.00445-16] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 11/08/2016] [Indexed: 12/14/2022]
Abstract
Plasmodium falciparum malaria remains the deadliest parasitic disease worldwide. Vaccines targeting the preerythrocytic sporozoite and liver stages have the potential to entirely prevent blood-stage infection and disease, as well as onward transmission. Sporozoite surface and secreted proteins are leading candidates for inclusion in a preerythrocytic stage-specific, antibody-based vaccine. Preclinical functional assays to identify humoral correlates of protection in vitro and to validate novel sporozoite protein targets for inclusion in multisubunit vaccines currently do not consider the interaction of sporozoite-targeting antibodies with other components of the immune system. Here, we describe the development of a simple flow cytometric assay to quantitatively assess the ability of antibodies directed against P. falciparum sporozoites to facilitate their phagocytosis. We demonstrate that this sporozoite opsonic phagocytosis assay (SOPA) is compatible with both monoclonal antibodies and human immune serum and can be performed using cryopreserved P. falciparum sporozoites. This simple, accessible assay will aid with the assessment of antibody responses to vaccination with Plasmodium antigens and their interaction with phagocytic cells of the immune system.
Collapse
|
23
|
Oakley MS, Verma N, Zheng H, Anantharaman V, Takeda K, Gao Y, Myers TG, Pham PT, Mahajan B, Kumar N, Sangweme D, Tripathi AK, Mlambo G, Aravind L, Kumar S. Molecular Markers of Radiation Induced Attenuation in Intrahepatic Plasmodium falciparum Parasites. PLoS One 2016; 11:e0166814. [PMID: 27911910 PMCID: PMC5135057 DOI: 10.1371/journal.pone.0166814] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 11/04/2016] [Indexed: 11/24/2022] Open
Abstract
Experimental immunization with radiation attenuated sporozoites (RAS) and genetically attenuated sporozoites has proved to be a promising approach for malaria vaccine development. However, parasite biomarkers of growth attenuation and enhanced immune protection in response to radiation remain poorly understood. Here, we report on the effect of an attenuating dose of γ-irradiation (15 krad) on the Plasmodium falciparum sporozoite (PfSPZ) ultrastructure by electron microscopy, growth rate of liver stage P. falciparum in liver cell cultures, and genome-wide transcriptional profile of liver stage parasites by microarray. We find that γ-irradiation treated PfSPZ retained a normal cellular structure except that they were vacuous with a partially disrupted plasma membrane and inner membrane complex. A similar infection rate was observed by γ-irradiation-treated and untreated PfSPZ in human HCO-4 liver cells (0.47% versus 0.49%, respectively) on day 3 post-infection. In the microarray studies, cumulatively, 180 liver stage parasite genes were significantly transcriptionally altered on day 3 and/or 6 post-infection. Among the transcriptionally altered biomarkers, we identified a signature of seven candidate parasite genes that associated with functionally diverse pathways that may regulate radiation induced cell cycle arrest of the parasite within the hepatocyte. A repertoire of 14 genes associated with protein translation is transcriptionally overexpressed within the parasite by radiation. Additionally, 37 genes encode proteins expressed on the cell surface or exported into the host cell, 4 encode membrane associated transporters, and 10 encode proteins related to misfolding and stress-related protein processing. These results have significantly increased the repertoire of novel targets for 1) biomarkers of safety to define proper attenuation, 2) generating genetically attenuated parasite vaccine candidates, and 3) subunit candidate vaccines against liver stage malaria.
Collapse
Affiliation(s)
- Miranda S. Oakley
- Division of Bacterial, Parasitic, and Allergenic Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, United States
| | - Nitin Verma
- Division of Bacterial, Parasitic, and Allergenic Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, United States
| | - Hong Zheng
- Division of Emerging and Transfusion Transmitted Diseases, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, United States
| | - Vivek Anantharaman
- National Center for Biotechnology Information, National Library of Medicine, NIH, Bethesda, Maryland, United States
| | - Kazuyo Takeda
- Division of Viral Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, United States
| | - Yamei Gao
- Division of Viral Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, United States
| | - Timothy G. Myers
- Genomics Technologies Section, Research Technologies Branch, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, United States
| | - Phuong Thao Pham
- Division of Emerging and Transfusion Transmitted Diseases, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, United States
| | - Babita Mahajan
- Division of Emerging and Transfusion Transmitted Diseases, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, United States
| | - Nirbhay Kumar
- Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States
| | - Davison Sangweme
- Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States
| | - Abhai K. Tripathi
- Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States
| | - Godfree Mlambo
- Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States
| | - L. Aravind
- National Center for Biotechnology Information, National Library of Medicine, NIH, Bethesda, Maryland, United States
| | - Sanjai Kumar
- Division of Emerging and Transfusion Transmitted Diseases, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, United States
- * E-mail:
| |
Collapse
|
24
|
Steel RW, Kappe SH, Sack BK. An expanding toolkit for preclinical pre-erythrocytic malaria vaccine development: bridging traditional mouse malaria models and human trials. Future Microbiol 2016; 11:1563-1579. [PMID: 27855488 DOI: 10.2217/fmb-2016-0077] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Malaria remains a significant public health burden with 214 million new infections and over 400,000 deaths in 2015. Elucidating relevant Plasmodium parasite biology can lead to the identification of novel ways to control and ultimately eliminate the parasite within geographic areas. Particularly, the development of an effective vaccine that targets the clinically silent pre-erythrocytic stages of infection would significantly augment existing malaria elimination tools by preventing both the onset of blood-stage infection/disease as well as spread of the parasite through mosquito transmission. In this Perspective, we discuss the role of small animal models in pre-erythrocytic stage vaccine development, highlighting how human liver-chimeric and human immune system mice are emerging as valuable components of these efforts.
Collapse
Affiliation(s)
- Ryan Wj Steel
- Center for Infectious Disease Research, Formerly Seattle Biomedical Research Institute, 307 Westlake Avenue North, Suite 500, Seattle, WA 98109, USA
| | - Stefan Hi Kappe
- Center for Infectious Disease Research, Formerly Seattle Biomedical Research Institute, 307 Westlake Avenue North, Suite 500, Seattle, WA 98109, USA
| | - Brandon K Sack
- Center for Infectious Disease Research, Formerly Seattle Biomedical Research Institute, 307 Westlake Avenue North, Suite 500, Seattle, WA 98109, USA
| |
Collapse
|
25
|
Longley RJ, Hill AVS, Spencer AJ. Malaria vaccines: identifying Plasmodium falciparum liver-stage targets. Front Microbiol 2015; 6:965. [PMID: 26441899 PMCID: PMC4569888 DOI: 10.3389/fmicb.2015.00965] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 08/31/2015] [Indexed: 01/08/2023] Open
Abstract
The development of a highly efficacious and durable vaccine for malaria remains a top priority for global health researchers. Despite the huge rise in recognition of malaria as a global health problem and the concurrent rise in funding over the past 10–15 years, malaria continues to remain a widespread burden. The evidence of increasing resistance to anti-malarial drugs and insecticides is a growing concern. Hence, an efficacious and durable preventative vaccine for malaria is urgently needed. Vaccines are one of the most cost-effective tools and have successfully been used in the prevention and control of many diseases, however, the development of a vaccine for the Plasmodium parasite has proved difficult. Given the early success of whole sporozoite mosquito-bite delivered vaccination strategies, we know that a vaccine for malaria is an achievable goal, with sub-unit vaccines holding great promise as they are simple and cheap to both manufacture and deploy. However a major difficulty in development of sub-unit vaccines lies within choosing the appropriate antigenic target from the 5000 or so genes expressed by the parasite. Given the liver-stage of malaria represents a bottle-neck in the parasite’s life cycle, there is widespread agreement that a multi-component sub-unit malaria vaccine should preferably contain a liver-stage target. In this article we review progress in identifying and screening Plasmodium falciparum liver-stage targets for use in a malaria vaccine.
Collapse
Affiliation(s)
- Rhea J Longley
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford Oxford, UK
| | - Adrian V S Hill
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford Oxford, UK
| | - Alexandra J Spencer
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford Oxford, UK
| |
Collapse
|
26
|
Soulard V, Bosson-Vanga H, Lorthiois A, Roucher C, Franetich JF, Zanghi G, Bordessoulles M, Tefit M, Thellier M, Morosan S, Le Naour G, Capron F, Suemizu H, Snounou G, Moreno-Sabater A, Mazier D. Plasmodium falciparum full life cycle and Plasmodium ovale liver stages in humanized mice. Nat Commun 2015. [PMID: 26205537 PMCID: PMC4525212 DOI: 10.1038/ncomms8690] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Experimental studies of Plasmodium parasites that infect humans are restricted by their host specificity. Humanized mice offer a means to overcome this and further provide the opportunity to observe the parasites in vivo. Here we improve on previous protocols to achieve efficient double engraftment of TK-NOG mice by human primary hepatocytes and red blood cells. Thus, we obtain the complete hepatic development of P. falciparum, the transition to the erythrocytic stages, their subsequent multiplication, and the appearance of mature gametocytes over an extended period of observation. Furthermore, using sporozoites derived from two P. ovale-infected patients, we show that human hepatocytes engrafted in TK-NOG mice sustain maturation of the liver stages, and the presence of late-developing schizonts indicate the eventual activation of quiescent parasites. Thus, TK-NOG mice are highly suited for in vivo observations on the Plasmodium species of humans. Mice engrafted with human cells are useful models for research on human malaria parasites. Here the authors show that the complete life cycle of Plasmodium falciparum and the liver stages of Plasmodium ovale can be studied in mice doubly engrafted with human primary hepatocytes and red blood cells.
Collapse
Affiliation(s)
- Valérie Soulard
- 1] Sorbonne Universités, UPMC Univ Paris 06, CR7, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), 91 Bd de l'hôpital, F-75013 Paris, France [2] INSERM, U1135, CIMI-PARIS, 91 Bd de l'hôpital, F-75013 Paris, France [3] CNRS, ERL 8255, CIMI-PARIS, 91 Bd de l'hôpital, F-75013 Paris, France
| | - Henriette Bosson-Vanga
- 1] Sorbonne Universités, UPMC Univ Paris 06, CR7, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), 91 Bd de l'hôpital, F-75013 Paris, France [2] INSERM, U1135, CIMI-PARIS, 91 Bd de l'hôpital, F-75013 Paris, France [3] CNRS, ERL 8255, CIMI-PARIS, 91 Bd de l'hôpital, F-75013 Paris, France [4] Université FHB, UFR SPB, Departement de Parasitologie-Mycologie, BP V 34 Abidjan, Ivory Coast
| | - Audrey Lorthiois
- 1] Sorbonne Universités, UPMC Univ Paris 06, CR7, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), 91 Bd de l'hôpital, F-75013 Paris, France [2] INSERM, U1135, CIMI-PARIS, 91 Bd de l'hôpital, F-75013 Paris, France [3] CNRS, ERL 8255, CIMI-PARIS, 91 Bd de l'hôpital, F-75013 Paris, France
| | - Clémentine Roucher
- 1] Sorbonne Universités, UPMC Univ Paris 06, CR7, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), 91 Bd de l'hôpital, F-75013 Paris, France [2] INSERM, U1135, CIMI-PARIS, 91 Bd de l'hôpital, F-75013 Paris, France [3] CNRS, ERL 8255, CIMI-PARIS, 91 Bd de l'hôpital, F-75013 Paris, France
| | - Jean-François Franetich
- 1] Sorbonne Universités, UPMC Univ Paris 06, CR7, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), 91 Bd de l'hôpital, F-75013 Paris, France [2] INSERM, U1135, CIMI-PARIS, 91 Bd de l'hôpital, F-75013 Paris, France [3] CNRS, ERL 8255, CIMI-PARIS, 91 Bd de l'hôpital, F-75013 Paris, France
| | - Gigliola Zanghi
- 1] Sorbonne Universités, UPMC Univ Paris 06, CR7, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), 91 Bd de l'hôpital, F-75013 Paris, France [2] INSERM, U1135, CIMI-PARIS, 91 Bd de l'hôpital, F-75013 Paris, France [3] CNRS, ERL 8255, CIMI-PARIS, 91 Bd de l'hôpital, F-75013 Paris, France
| | - Mallaury Bordessoulles
- 1] Sorbonne Universités, UPMC Univ Paris 06, CR7, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), 91 Bd de l'hôpital, F-75013 Paris, France [2] INSERM, U1135, CIMI-PARIS, 91 Bd de l'hôpital, F-75013 Paris, France [3] CNRS, ERL 8255, CIMI-PARIS, 91 Bd de l'hôpital, F-75013 Paris, France
| | - Maurel Tefit
- 1] Sorbonne Universités, UPMC Univ Paris 06, CR7, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), 91 Bd de l'hôpital, F-75013 Paris, France [2] INSERM, U1135, CIMI-PARIS, 91 Bd de l'hôpital, F-75013 Paris, France [3] CNRS, ERL 8255, CIMI-PARIS, 91 Bd de l'hôpital, F-75013 Paris, France
| | - Marc Thellier
- AP-HP, Groupe Hospitalier Pitié-Salpêtrière, Service Parasitologie-Mycologie, Centre National de Référence du Paludisme, 83 Bd de l'hôpital, F-75013 Paris, France
| | - Serban Morosan
- UPMC Univ. Paris 06, INSERM, UMS28, 105 Bd de l'hôpital, F-75013 Paris, France
| | - Gilles Le Naour
- AP-HP, UPMC Univ. Paris 06, Groupe Hospitalier Pitié-Salpêtrière, Service d'anatomie et cytologie pathologiques, 83 Bd de l'hôpital, F-75013 Paris, France
| | - Frédérique Capron
- AP-HP, UPMC Univ. Paris 06, Groupe Hospitalier Pitié-Salpêtrière, Service d'anatomie et cytologie pathologiques, 83 Bd de l'hôpital, F-75013 Paris, France
| | - Hiroshi Suemizu
- Central Institute for Experimental Animal, Kawasaki, Kanegawa, Japan
| | - Georges Snounou
- 1] Sorbonne Universités, UPMC Univ Paris 06, CR7, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), 91 Bd de l'hôpital, F-75013 Paris, France [2] INSERM, U1135, CIMI-PARIS, 91 Bd de l'hôpital, F-75013 Paris, France [3] CNRS, ERL 8255, CIMI-PARIS, 91 Bd de l'hôpital, F-75013 Paris, France
| | - Alicia Moreno-Sabater
- 1] Sorbonne Universités, UPMC Univ Paris 06, CR7, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), 91 Bd de l'hôpital, F-75013 Paris, France [2] INSERM, U1135, CIMI-PARIS, 91 Bd de l'hôpital, F-75013 Paris, France [3] CNRS, ERL 8255, CIMI-PARIS, 91 Bd de l'hôpital, F-75013 Paris, France
| | - Dominique Mazier
- 1] Sorbonne Universités, UPMC Univ Paris 06, CR7, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), 91 Bd de l'hôpital, F-75013 Paris, France [2] INSERM, U1135, CIMI-PARIS, 91 Bd de l'hôpital, F-75013 Paris, France [3] CNRS, ERL 8255, CIMI-PARIS, 91 Bd de l'hôpital, F-75013 Paris, France [4] AP-HP, Groupe Hospitalier Pitié-Salpêtrière, Service Parasitologie-Mycologie, Centre National de Référence du Paludisme, 83 Bd de l'hôpital, F-75013 Paris, France
| |
Collapse
|
27
|
Kumar S, Kumari R, Pandey R. New insight-guided approaches to detect, cure, prevent and eliminate malaria. PROTOPLASMA 2015; 252:717-753. [PMID: 25323622 DOI: 10.1007/s00709-014-0697-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Accepted: 09/01/2014] [Indexed: 06/04/2023]
Abstract
New challenges posed by the development of resistance against artemisinin-based combination therapies (ACTs) as well as previous first-line therapies, and the continuing absence of vaccine, have given impetus to research in all areas of malaria control. This review portrays the ongoing progress in several directions of malaria research. The variants of RTS,S and apical membrane antigen 1 (AMA1) are being developed and test adapted as multicomponent and multistage malaria control vaccines, while many other vaccine candidates and methodologies to produce antigens are under experimentation. To track and prevent the spread of artemisinin resistance from Southeast Asia to other parts of the world, rolling circle-enhanced enzyme activity detection (REEAD), a time- and cost-effective malaria diagnosis in field conditions, and a DNA marker associated with artemisinin resistance have become available. Novel mosquito repellents and mosquito trapping and killing techniques much more effective than the prevalent ones are undergoing field testing. Mosquito lines stably infected with their symbiotic wild-type or genetically engineered bacteria that kill sympatric malaria parasites are being constructed and field tested for stopping malaria transmission. A complementary approach being pursued is the addition of ivermectin-like drug molecules to ACTs to cure malaria and kill mosquitoes. Experiments are in progress to eradicate malaria mosquito by making it genetically male sterile. High-throughput screening procedures are being developed and used to discover molecules that possess long in vivo half life and are active against liver and blood stages for the fast cure of malaria symptoms caused by simple or relapsing and drug-sensitive and drug-resistant types of varied malaria parasites, can stop gametocytogenesis and sporogony and could be given in one dose. Target-based antimalarial drug designing has begun. Some of the putative next-generation antimalarials that possess in their scaffold structure several of the desired properties of malaria cure and control are exemplified by OZ439, NITD609, ELQ300 and tafenoquine that are already undergoing clinical trials, and decoquinate, usnic acid, torin-2, ferroquine, WEHI-916, MMV396749 and benzothiophene-type N-myristoyltransferase (NMT) inhibitors, which are candidates for future clinical usage. Among these, NITD609, ELQ300, decoquinate, usnic acid, torin-2 and NMT inhibitors not only cure simple malaria and are prophylactic against simple malaria, but they also cure relapsing malaria.
Collapse
Affiliation(s)
- Sushil Kumar
- SKA Institution for Research, Education and Development (SKAIRED), 4/11 SarvPriya Vihar, New Delhi, 110016, India,
| | | | | |
Collapse
|
28
|
Longley RJ, Bauza K, Ewer KJ, Hill AVS, Spencer AJ. Development of an in vitro assay and demonstration of Plasmodium berghei liver-stage inhibition by TRAP-specific CD8+ T cells. PLoS One 2015; 10:e0119880. [PMID: 25822951 PMCID: PMC4379172 DOI: 10.1371/journal.pone.0119880] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 02/03/2015] [Indexed: 01/20/2023] Open
Abstract
The development of an efficacious vaccine against the Plasmodium parasite remains a top priority. Previous research has demonstrated the ability of a prime-boost virally vectored sub-unit vaccination regimen, delivering the liver-stage expressed malaria antigen TRAP, to produce high levels of antigen-specific T cells. The liver-stage of malaria is the main target of T cell-mediated immunity, yet a major challenge in assessing new T cell inducing vaccines has been the lack of a suitable pre-clinical assay. We have developed a flow-cytometry based in vitro T cell killing assay using a mouse hepatoma cell line, Hepa1-6, and Plasmodium berghei GFP expressing sporozoites. Using this assay, P. berghei TRAP-specific CD8+ T cell enriched splenocytes were shown to inhibit liver-stage parasites in an effector-to-target ratio dependent manner. Further development of this assay using human hepatocytes and P. falciparum would provide a new method to pre-clinically screen vaccine candidates and to elucidate mechanisms of protection in vitro.
Collapse
Affiliation(s)
- Rhea J Longley
- The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Karolis Bauza
- The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Katie J Ewer
- The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Adrian V S Hill
- The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | | |
Collapse
|
29
|
Wijayalath W, Majji S, Villasante EF, Brumeanu TD, Richie TL, Casares S. Humanized HLA-DR4.RagKO.IL2RγcKO.NOD (DRAG) mice sustain the complex vertebrate life cycle of Plasmodium falciparum malaria. Malar J 2014; 13:386. [PMID: 25266106 PMCID: PMC4197321 DOI: 10.1186/1475-2875-13-386] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 09/18/2014] [Indexed: 12/28/2022] Open
Abstract
Background Malaria is a deadly infectious disease affecting millions of people in tropical and sub-tropical countries. Among the five species of Plasmodium parasites that infect humans, Plasmodium falciparum accounts for the highest morbidity and mortality associated with malaria. Since humans are the only natural hosts for P. falciparum, the lack of convenient animal models has hindered the understanding of disease pathogenesis and prompted the need of testing anti-malarial drugs and vaccines directly in human trials. Humanized mice hosting human cells represent new pre-clinical models for infectious diseases that affect only humans. In this study, the ability of human-immune-system humanized HLA-DR4.RagKO.IL2RγcKO.NOD (DRAG) mice to sustain infection with P. falciparum was explored. Methods Four week-old DRAG mice were infused with HLA-matched human haematopoietic stem cells (HSC) and examined for reconstitution of human liver cells and erythrocytes. Upon challenge with infectious P. falciparum sporozoites (NF54 strain) humanized DRAG mice were examined for liver stage infection, blood stage infection, and transmission to Anopheles stephensi mosquitoes. Results Humanized DRAG mice reconstituted human hepatocytes, Kupffer cells, liver endothelial cells, and erythrocytes. Upon intravenous challenge with P. falciparum sporozoites, DRAG mice sustained liver to blood stage infection (average 3–5 parasites/microlitre blood) and allowed transmission to An. stephensi mosquitoes. Infected DRAG mice elicited antibody and cellular responses to the blood stage parasites and self-cured the infection by day 45 post-challenge. Conclusions DRAG mice represent the first human-immune-system humanized mouse model that sustains the complex vertebrate life cycle of P. falciparum without the need of exogenous injection of human hepatocytes/erythrocytes or P. falciparum parasite adaptation. The ability of DRAG mice to elicit specific human immune responses to P. falciparum parasites may help deciphering immune correlates of protection and to identify protective malaria antigens.
Collapse
Affiliation(s)
| | | | | | | | | | - Sofia Casares
- US Military Malaria Vaccine Program, Naval Medical Research Center/Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA.
| |
Collapse
|