1
|
Williams BG, King LDW, Pulido D, Quinkert D, Lias AM, Silk SE, Ragotte RJ, Davies H, Barrett JR, McHugh K, Rigby CA, Alanine DGW, Barfod L, Shea MW, Cowley LA, Dabbs RA, Pattinson DJ, Douglas AD, Lyth OR, Illingworth JJ, Jin J, Carnrot C, Kotraiah V, Christen JM, Noe AR, MacGill RS, King CR, Birkett AJ, Soisson LA, Skinner K, Miura K, Long CA, Higgins MK, Draper SJ. Development of an improved blood-stage malaria vaccine targeting the essential RH5-CyRPA-RIPR invasion complex. Nat Commun 2024; 15:4857. [PMID: 38849365 PMCID: PMC11161584 DOI: 10.1038/s41467-024-48721-3] [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: 02/20/2024] [Accepted: 05/10/2024] [Indexed: 06/09/2024] Open
Abstract
Reticulocyte-binding protein homologue 5 (RH5), a leading blood-stage Plasmodium falciparum malaria vaccine target, interacts with cysteine-rich protective antigen (CyRPA) and RH5-interacting protein (RIPR) to form an essential heterotrimeric "RCR-complex". We investigate whether RCR-complex vaccination can improve upon RH5 alone. Using monoclonal antibodies (mAbs) we show that parasite growth-inhibitory epitopes on each antigen are surface-exposed on the RCR-complex and that mAb pairs targeting different antigens can function additively or synergistically. However, immunisation of female rats with the RCR-complex fails to outperform RH5 alone due to immuno-dominance of RIPR coupled with inferior potency of anti-RIPR polyclonal IgG. We identify that all growth-inhibitory antibody epitopes of RIPR cluster within the C-terminal EGF-like domains and that a fusion of these domains to CyRPA, called "R78C", combined with RH5, improves the level of in vitro parasite growth inhibition compared to RH5 alone. These preclinical data justify the advancement of the RH5.1 + R78C/Matrix-M™ vaccine candidate to Phase 1 clinical trial.
Collapse
Affiliation(s)
- Barnabas G Williams
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, Oxford, UK
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Lloyd D W King
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, Oxford, UK
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - David Pulido
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Doris Quinkert
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, Oxford, UK
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Amelia M Lias
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, Oxford, UK
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Sarah E Silk
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, Oxford, UK
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Robert J Ragotte
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford, UK
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Hannah Davies
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, Oxford, UK
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Jordan R Barrett
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, Oxford, UK
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Kirsty McHugh
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, Oxford, UK
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Cassandra A Rigby
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, Oxford, UK
| | - Daniel G W Alanine
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford, UK
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Lea Barfod
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Michael W Shea
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Li An Cowley
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford, UK
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Rebecca A Dabbs
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - David J Pattinson
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Alexander D Douglas
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Oliver R Lyth
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford, UK
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Joseph J Illingworth
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Jing Jin
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | | | | | | | - Amy R Noe
- Leidos Life Sciences, Frederick, MD, USA
- Latham BioPharm Group, Elkridge, MD, USA
| | | | - C Richter King
- Center for Vaccine Innovation and Access, PATH, Washington, DC, USA
| | - Ashley J Birkett
- Center for Vaccine Innovation and Access, PATH, Washington, DC, USA
| | | | - Katherine Skinner
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, Oxford, UK
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK
| | - Kazutoyo Miura
- Laboratory of Malaria and Vector Research, NIAID/NIH, Rockville, MD, USA
| | - Carole A Long
- Laboratory of Malaria and Vector Research, NIAID/NIH, Rockville, MD, USA
| | - Matthew K Higgins
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford, UK
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, Oxford, UK
| | - Simon J Draper
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford, UK.
- Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, Oxford, UK.
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, UK.
- NIHR Oxford Biomedical Research Centre, Oxford, UK.
| |
Collapse
|
2
|
Takashima E, Otsuki H, Morita M, Ito D, Nagaoka H, Yuguchi T, Hassan I, Tsuboi T. The Need for Novel Asexual Blood-Stage Malaria Vaccine Candidates for Plasmodium falciparum. Biomolecules 2024; 14:100. [PMID: 38254700 PMCID: PMC10813614 DOI: 10.3390/biom14010100] [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: 10/03/2023] [Revised: 12/25/2023] [Accepted: 01/09/2024] [Indexed: 01/24/2024] Open
Abstract
Extensive control efforts have significantly reduced malaria cases and deaths over the past two decades, but in recent years, coupled with the COVID-19 pandemic, success has stalled. The WHO has urged the implementation of a number of interventions, including vaccines. The modestly effective RTS,S/AS01 pre-erythrocytic vaccine has been recommended by the WHO for use in sub-Saharan Africa against Plasmodium falciparum in children residing in moderate to high malaria transmission regions. A second pre-erythrocytic vaccine, R21/Matrix-M, was also recommended by the WHO on 3 October 2023. However, the paucity and limitations of pre-erythrocytic vaccines highlight the need for asexual blood-stage malaria vaccines that prevent disease caused by blood-stage parasites. Few asexual blood-stage vaccine candidates have reached phase 2 clinical development, and the challenges in terms of their efficacy include antigen polymorphisms and low immunogenicity in humans. This review summarizes the history and progress of asexual blood-stage malaria vaccine development, highlighting the need for novel candidate vaccine antigens/molecules.
Collapse
Affiliation(s)
- Eizo Takashima
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama 790-8577, Japan; (M.M.); (H.N.); (T.Y.); (I.H.)
| | - Hitoshi Otsuki
- Division of Medical Zoology, Department of Microbiology and Immunology, Faculty of Medicine, Tottori University, Yonago 683-8503, Japan; (H.O.); (D.I.)
| | - Masayuki Morita
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama 790-8577, Japan; (M.M.); (H.N.); (T.Y.); (I.H.)
| | - Daisuke Ito
- Division of Medical Zoology, Department of Microbiology and Immunology, Faculty of Medicine, Tottori University, Yonago 683-8503, Japan; (H.O.); (D.I.)
| | - Hikaru Nagaoka
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama 790-8577, Japan; (M.M.); (H.N.); (T.Y.); (I.H.)
| | - Takaaki Yuguchi
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama 790-8577, Japan; (M.M.); (H.N.); (T.Y.); (I.H.)
| | - Ifra Hassan
- Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama 790-8577, Japan; (M.M.); (H.N.); (T.Y.); (I.H.)
| | - Takafumi Tsuboi
- Division of Cell-Free Sciences, Proteo-Science Center, Ehime University, Matsuyama 790-8577, Japan
| |
Collapse
|
3
|
Tamborrini M, Schäfer A, Hauser J, Zou L, Paris DH, Pluschke G. The malaria blood stage antigen PfCyRPA formulated with the TLR-4 agonist adjuvant GLA-SE elicits parasite growth inhibitory antibodies in experimental animals. Malar J 2023; 22:210. [PMID: 37454145 DOI: 10.1186/s12936-023-04638-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 07/01/2023] [Indexed: 07/18/2023] Open
Abstract
BACKGROUND Plasmodium falciparum cysteine-rich protective antigen (PfCyRPA) is an invasion complex protein essential for erythrocyte invasion. In contrast to several previously clinically tested merozoite vaccine candidate antigens, PfCyRPA is not polymorphic, making it a promising candidate antigen for blood stage vaccine development. METHODS Mice and rabbits were immunized with vaccine formulations of recombinantly expressed PfCyRPA adjuvanted either with the glucopyranosyl lipid A (GLA) containing adjuvants GLA-LSQ, GLA-SE, GLA-Alum or with Nanoalum. ELISA and indirect immunofluorescence assays (IFA) were used to analyse elicited IgG titers and the P. falciparum growth inhibitory activity was determined with a standardized in vitro [3H]-hypoxanthine incorporation assay. RESULTS In the mouse experiments, the GLA adjuvanted formulations were superior to the Nanoalum formulation with respect to antibody titer development, IFA sero-conversion rates and in vitro parasite growth-inhibitory activity. In rabbits, the highest titers of parasite growth inhibitory antibodies were obtained with the GLA-SE formulation. Comparable mean ELISA IgG endpoint titers were reached in rabbits after three immunizations with GLA-SE adjuvanted PfCyRPA doses of 5, 25 and 100 µg, but with 100 µg of antigen, only two immunizations were required to reach this titer. CONCLUSION PfCyRPA formulated with the human-compatible adjuvant GLA-SE represents an attractive vaccine candidate for early clinical testing in a controlled P. falciparum blood stage challenge trial.
Collapse
Affiliation(s)
- Marco Tamborrini
- Swiss Tropical and Public Health Institute, Kreuzstrasse 2, 4123, Allschwil, Switzerland
- University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Anja Schäfer
- Swiss Tropical and Public Health Institute, Kreuzstrasse 2, 4123, Allschwil, Switzerland
- University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Julia Hauser
- Swiss Tropical and Public Health Institute, Kreuzstrasse 2, 4123, Allschwil, Switzerland
- University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Linghui Zou
- Swiss Tropical and Public Health Institute, Kreuzstrasse 2, 4123, Allschwil, Switzerland
- University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Daniel H Paris
- Swiss Tropical and Public Health Institute, Kreuzstrasse 2, 4123, Allschwil, Switzerland
- University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, Kreuzstrasse 2, 4123, Allschwil, Switzerland.
- University of Basel, Petersplatz 1, 4001, Basel, Switzerland.
| |
Collapse
|
4
|
Waweru H, Kanoi BN, Kuja JO, Maranga M, Kongere J, Maina M, Kinyua J, Gitaka J. Limited genetic variations of the Rh5-CyRPA-Ripr invasion complex in Plasmodium falciparum parasite population in selected malaria-endemic regions, Kenya. FRONTIERS IN TROPICAL DISEASES 2023; 4:1102265. [PMID: 38406638 PMCID: PMC7615667 DOI: 10.3389/fitd.2023.1102265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2024] Open
Abstract
The invasion of human erythrocytes by Plasmodium falciparum merozoites requires interaction between parasite ligands and host receptors. Interaction of PfRh5-CyRPA-Ripr protein complex with basigin, an erythrocyte surface receptor, via PfRh5 is essential for erythrocyte invasion. Antibodies raised against each antigen component of the complex have demonstrated erythrocyte invasion inhibition, making these proteins potential blood-stage vaccine candidates. Genetic polymorphisms present a significant challenge in developing efficacious vaccines, leading to variant-specific immune responses. This study investigated the genetic variations of the PfRh5 complex proteins in P. falciparum isolates from Lake Victoria islands, Western Kenya. Here, twenty-nine microscopically confirmed P. falciparum field samples collected from islands in Lake Victoria between July 2014 and July 2016 were genotyped by whole genome sequencing, and results compared to sequences mined from the GenBank database, from a study conducted in Kilifi, as well as other sequences from the MalariaGEN repository. We analyzed the frequency of polymorphisms in the PfRh5 protein complex proteins, PfRh5, PfCyRPA, PfRipr, and PfP113, and their location mapped on the 3D protein complex structure. We identified a total of 58 variants in the PfRh5 protein complex. PfRh5 protein was the most polymorphic with 30 SNPs, while PfCyRPA was relatively conserved with 3 SNPs. The minor allele frequency of the SNPs ranged between 1.9% and 21.2%. Ten high-frequency alleles (>5%) were observed in PfRh5 at codons 147, 148, 277, 410, and 429 and in PfRipr at codons 190, 255, 259, and 1003. A SNP was located in protein-protein interaction region C203Y and F292V of PfRh5 and PfCyRPA, respectively. Put together, this study revealed low polymorphisms in the PfRh5 invasion complex in the Lake Victoria parasite population. However, the two mutations identified on the protein interaction regions prompts for investigation on their impacts on parasite invasion process to support the consideration of PfRh5 components as potential malaria vaccine candidates.
Collapse
Affiliation(s)
- Harrison Waweru
- Centre for Research in Infectious Diseases, Directorate of Research and Innovation, Mount Kenya University, Thika, Kenya
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
| | - Bernard N. Kanoi
- Centre for Research in Infectious Diseases, Directorate of Research and Innovation, Mount Kenya University, Thika, Kenya
- Centre for Research in Tropical Medicine and Community Development, Nairobi, Kenya
| | - Josiah O. Kuja
- Centre for Research in Infectious Diseases, Directorate of Research and Innovation, Mount Kenya University, Thika, Kenya
- Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Mary Maranga
- Malopolska Centre of Biotechnology, Jagiellonian University, Kraków, Poland
| | - James Kongere
- Centre for Research in Tropical Medicine and Community Development, Nairobi, Kenya
| | - Michael Maina
- Centre for Research in Infectious Diseases, Directorate of Research and Innovation, Mount Kenya University, Thika, Kenya
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
| | - Johnson Kinyua
- Department of Biochemistry, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
| | - Jesse Gitaka
- Centre for Research in Infectious Diseases, Directorate of Research and Innovation, Mount Kenya University, Thika, Kenya
- Centre for Research in Tropical Medicine and Community Development, Nairobi, Kenya
| |
Collapse
|
5
|
Chi H, Tian S, Li X, Chen Y, Xu Q, Wang Q, Shi W, Adu-Frimpong M, Tong S. Construction of lipid raft-coupled agarose gels as bioaffinity chromatography materials and validation with tropomyosin-related kinase A-targeted drugs. J Chromatogr A 2023; 1691:463803. [PMID: 36731332 DOI: 10.1016/j.chroma.2023.463803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 01/04/2023] [Accepted: 01/13/2023] [Indexed: 01/15/2023]
Abstract
In order to improve the separation process of affinity chromatography that has silica as the main carrier material, we sought to construct Lipid Rafts@CNBr-Sepharose 4B affinity chromatography model. We extracted the lipid rafts from U251 cells with a descaler method and sucrose density gradient centrifugation. Afterwards, it was discovered via immunofluorescence that the lipid rafts contain a large amount of tropomyosin-related kinase A (TrkA) protein. Also, agarose powder in the lyophilised state was pretreated, before the lipid rafts were coupled to the agarose gel in a coupling buffer of alkaline pH. CNBr-Sepharose 4B affinity gel packing was characterised using UV spectrophotometric, immunofluorescence and scanning electron microscopic techniques, wherein and the results showed that the lipid rafts were successfully coupled to the agarose gels. Three compounds were used to verify the specific sorption of Sepharose 4B and CNBr-Sepharose 4B, which showed no specific sorption on the materials. Of note, the prepared Lipid Rafts@CNBr-Sepharose 4B agarose gels packed with TrkA-rich target proteins could be successfully validated for the active drug gefitinib with high affinity sorption efficiency and eluted with good recovery and reproducibility. This study broadens the range of affinity chromatography carrier materials and provides a reference for research in active drug screening.
Collapse
Affiliation(s)
- Hao Chi
- School of Pharmacy, Jiangsu University, Zhenjiang, Jiangsu, 212000, China
| | - Sheng Tian
- School of Pharmacy, Jiangsu University, Zhenjiang, Jiangsu, 212000, China
| | - Xiu Li
- School of Pharmacy, Jiangsu University, Zhenjiang, Jiangsu, 212000, China
| | - Yuchu Chen
- School of Pharmacy, Jiangsu University, Zhenjiang, Jiangsu, 212000, China
| | - Qiumin Xu
- School of Pharmacy, Jiangsu University, Zhenjiang, Jiangsu, 212000, China
| | - Qixiao Wang
- School of Pharmacy, Jiangsu University, Zhenjiang, Jiangsu, 212000, China
| | - Wenwan Shi
- School of Pharmacy, Jiangsu University, Zhenjiang, Jiangsu, 212000, China
| | - Michael Adu-Frimpong
- School of Chemical and Biochemical Sciences, C. K. Tedam University of Technology and Applied Sciences (CKT-UTAS), Navrongo, UK-0215-5321, Ghana
| | - Shanshan Tong
- School of Pharmacy, Jiangsu University, Zhenjiang, Jiangsu, 212000, China.
| |
Collapse
|
6
|
Computational Clues of Immunogenic Hotspots in Plasmodium falciparum Erythrocytic Stage Vaccine Candidate Antigens: In Silico Approach. BIOMED RESEARCH INTERNATIONAL 2022; 2022:5886687. [PMID: 36277884 PMCID: PMC9584662 DOI: 10.1155/2022/5886687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Accepted: 09/27/2022] [Indexed: 11/30/2022]
Abstract
Malaria is the most pernicious parasitic infection, and Plasmodium falciparum is the most virulent species with substantial morbidity and mortality worldwide. The present in silico investigation was performed to reveal the biophysical characteristics and immunogenic epitopes of the 14 blood-stage proteins of the P. falciparum using comprehensive immunoinformatics approaches. For this aim, various web servers were employed to predict subcellular localization, antigenicity, allergenicity, solubility, physicochemical properties, posttranslational modification sites (PTMs), the presence of signal peptide, and transmembrane domains. Moreover, structural analysis for secondary and 3D model predictions were performed for all and stable proteins, respectively. Finally, human helper T lymphocyte (HTL) epitopes were predicted using HLA reference set of IEDB server and screened in terms of antigenicity, allergenicity, and IFN-γ induction as well as population coverage. Also, a multiserver B-cell epitope prediction was done with subsequent screening for antigenicity, allergenicity, and solubility. Altogether, these proteins showed appropriate antigenicity, abundant PTMs, and many B-cell and HTL epitopes, which could be directed for future vaccination studies in the context of multiepitope vaccine design.
Collapse
|
7
|
Somanathan A, Mian SY, Chaddha K, Uchoi S, Bharti PK, Tandon R, Gaur D, Chauhan VS. Process development and preclinical evaluation of a major Plasmodium falciparum blood stage vaccine candidate, Cysteine-Rich Protective Antigen (CyRPA). Front Immunol 2022; 13:1005332. [PMID: 36211427 PMCID: PMC9535676 DOI: 10.3389/fimmu.2022.1005332] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 08/31/2022] [Indexed: 11/13/2022] Open
Abstract
Plasmodium falciparum Cysteine-Rich Protective Antigen (CyRPA) is an essential, highly conserved merozoite antigen that forms an important multi-protein complex (RH5/Ripr/CyRPA) necessary for erythrocyte invasion. CyRPA is a promising blood-stage vaccine target that has been shown to elicit potent strain-transcending parasite neutralizing antibodies. Recently, we demonstrated that naturally acquired immune anti-CyRPA antibodies are invasion-inhibitory and therefore a correlate of protection against malaria. Here, we describe a process for the large-scale production of tag-free CyRPA vaccine in E. coli and demonstrate its parasite neutralizing efficacy with commonly used adjuvants. CyRPA was purified from inclusion bodies using a one-step purification method with high purity (>90%). Biochemical and biophysical characterization showed that the purified tag-free CyRPA interacted with RH5, readily detected by a conformation-specific CyRPA monoclonal antibody and recognized by sera from malaria infected individuals thus indicating that the recombinant antigen was correctly folded and retained its native conformation. Tag-free CyRPA formulated with Freund’s adjuvant elicited highly potent parasite neutralizing antibodies achieving inhibition of >90% across diverse parasite strains. Importantly, we identified tag-free CyRPA/Alhydrogel formulation as most effective in inducing a highly immunogenic antibody response that exhibited efficacious, cross-strain in vitro parasite neutralization achieving ~80% at 10 mg/ml. Further, CyRPA/Alhydrogel vaccine induced anti-parasite cytokine response in mice. In summary, our study provides a simple, scalable, cost-effective process for the production of tag-free CyRPA that in combination with human-compatible adjuvant induces efficacious humoral and cell-mediated immune response.
Collapse
Affiliation(s)
- Anjali Somanathan
- Laboratory of Malaria and Vaccine Research, School of Biotechnology, Jawaharlal Nehru University, New Delhi, India
| | - Syed Yusuf Mian
- Laboratory of Malaria and Vaccine Research, School of Biotechnology, Jawaharlal Nehru University, New Delhi, India
| | - Kritika Chaddha
- Laboratory of Malaria and Vaccine Research, School of Biotechnology, Jawaharlal Nehru University, New Delhi, India
| | - Seemalata Uchoi
- Laboratory of Malaria and Vaccine Research, School of Biotechnology, Jawaharlal Nehru University, New Delhi, India
| | - Praveen K. Bharti
- ICMR-National Institute of Research in Tribal Health (NIRTH), Jabalpur, India
| | - Ravi Tandon
- Laboratory of AIDS Research and Immunology, School of Biotechnology, Jawaharlal Nehru University, New Delhi, India
| | - Deepak Gaur
- Laboratory of Malaria and Vaccine Research, School of Biotechnology, Jawaharlal Nehru University, New Delhi, India
| | - Virander Singh Chauhan
- Malaria Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
- *Correspondence: Virander Singh Chauhan,
| |
Collapse
|