Antibody responses within two leading Plasmodium vivax vaccine candidate antigens in three geographically diverse malaria-endemic regions of India

• Published in: Malaria Journal
• Main Authors: Sonal Kale, Chander P. Yadav, Pavitra N. Rao, Sneh Shalini, Alex Eapen, Harish C. Srivasatava, Surya K. Sharma, Veena Pande, Jane M. Carlton, Om P. Singh, Prashant K. Mallick
• Format: Article in Journal/Newspaper
• Language: English
• Published: BMC 2019
• Subjects: Plasmodium vivax; PvAMA-1; PvMSP-119; Antibody response; Seroprevalence; India; Arctic medicine. Tropical medicine; RC955-962; Infectious and parasitic diseases; RC109-216; Arctic; Indian
• Online Access: https://doi.org/10.1186/s12936-019-3066-6; https://doaj.org/article/57bc6dad5e394c60af7e8c07f4af14b9

Abstract Background Identifying highly immunogenic blood stage antigens which can work as target for naturally acquired antibodies in different eco-epidemiological settings is an important step for designing malaria vaccine. Blood stage proteins of Plasmodium vivax, apical membrane antigen-1 (PvAMA-1) and 19 kDa fragment of merozoite surface protein (PvMSP-119) are such promising vaccine candidate antigens. This study determined the naturally-acquired antibody response to PvAMA-1 and PvMSP-119 antigens in individuals living in three geographically diverse malaria endemic regions of India. Methods A total of 234 blood samples were collected from individuals living in three different eco-epidemiological settings, Chennai, Nadiad, and Rourkela of India. Indirect ELISA was performed to measure human IgG antibodies against recombinant PvAMA-1 and PvMSP-119 antigens. The difference in seroprevalence and factors associated with antibody responses at each site was statistically analysed. Results The overall seroprevalence was 40.6% for PvAMA-1 and 62.4% for PvMSP-119. Seroprevalence to PvAMA-1 was higher in Chennai (47%) followed by Nadiad (46.7%) and Rourkela (27.6%). For PvMSP-119, seroprevalence was higher in Chennai (80.3%) as compared to Nadiad (53.3%) and Rourkela (57.9%). Seroprevalence for both the antigens were found to be higher in Chennai where P. vivax is the dominant malaria species. In addition, heterogeneous antibody response was observed for PvAMA-1 and PvMSP-119 antigens at each of the study sites. Two factors, age and malaria positivity were significantly associated with seropositivity for both the antigens PvAMA-1 and PvMSP-119. Conclusion These data suggest that natural acquired antibody response is higher for PvMSP-119 antigen as compared to PvAMA-1 antigen in individuals living in three geographically diverse malaria endemic regions in India. PvMSP-119 appears to be highly immunogenic in Indian population and has great potential as a malaria vaccine candidate. The differences in immune response ...