Characterization of IgG against recombinant protein of Plasmodium vivax merozoite surface antigen ? 1 in a malaria exposed population accompanied by longitudinal cohort.
Malaria remains one of the major public healthy problems in South and Central America Plasmodium vivax is the main species responsible for infection. The recombinant DNA technology has helped epidemiologic investigations to find a vaccine and merozoite surface protein- 1 (MSP-1) has been one of them. In this study we investigated the acquisition of IgG against the N-terminus and C-terminus of Plasmodium vivax merozoite protein (PvMSP-1) in a malaria exposed population where asymptomatic cases of malaria vivax had been observed. A strong correlation between IgG specific for the anti-N-terminus of MSP-1 and time of residence in the endemic area was found, together with progressive increasing of number of older residents presenting these antibodies. We observed that the last febrile attack malaria reported by residents with IgG anti-N-terminal was 8,6 years in average, while among residents of the same area without these antibodies the reported value was 2,6 years. No difference in anti-C-terminus titers was found. Comparing acquisition of these antibodies among residents in three groups: asymptomatic, symptomatic or not infected residents during a longitudinal study, we found that the asymptomatic group presented higher longenity IgG anti-N-terminus than others groups. Our results indicate that IgG anti-N-terminus PvMSP-1 could be correlated to protective immunity of asymptomatic to vivax malaria and suggest that antibodies are possibly markers of protection in natural infections of vivax malaria.
Advisor:Paulo Afonso Nogueira
School:Fundação Universidade Federal de Rondônia
Source Type:Master's Thesis
Date of Publication:12/01/2005