Acquired immune responses to the N- and C-terminal regions of Plasmodium vivax merozoite surface protein 1 in individuals exposed to malaria
Soares, Irene S
Saouza, José Maria de
Del Portillo, Hernando A
Rodrigues, Mauricio M
In this study, we evaluated the naturally acquired immune response to Plasmodium vivax merozoite surface protein 1 (PvMSP1) in individuals with recent clinical episodes of malaria from the state of Para´, Brazil. Ten recombinant proteins representing the first 682 amino acids (aa) of the N-terminal region and one representing the final 111 aa of the C-terminal region were expressed in Escherichia coli as glutathione S-transferase fusion proteins. Both of these regions have been suggested as candidates for development of a vaccine against Plasmodium sp. The total frequencies of individuals with antibodies and cellular immune responses to PvMSP1 were high (83.8 and 75%, respectively). The recombinant proteins representing the N- and C-terminal regions were recognized by 51.4 and 64.1% of sera, respectively. The frequency of responders to the C-terminal region increased according to the number of previous malaria episodes, reaching 83.3% after four episodes. Cellular immune response was measured by in vitro proliferation and gamma interferon production. Peripheral blood mononuclear cells of 75 and 47.2% of individuals proliferated in response to stimulation by the N- and C-terminal regions, respectively. Also, we found that one protein representing the N terminus and a second representing the C terminus of PvMSP1 stimulated 54.5% of individuals to secrete gamma interferon. We concluded that PvMSP1 is immunogenic to a large proportion of individuals exposed to malaria. Our results also suggested that the C-terminal region of PvMSP1 containing the two epidermal growth factor-like domains is particularly immunogenic to antibodies and T cells during natural infection in humans.
xmlui.dri2xhtml.METS-1.0.item-citationSOARES, Irene S. et al. Acquired immune responses to the N- and C-terminal regions of Plasmodium vivax merozoite surface protein 1 in individuals exposed to malaria. Infection and Immunity, v. 65, n. 5, p. 1606-1614, May 1997.
Proteína 1 de Superfície de Merozoito
Precursores de Proteínas
Ensaio de Imunoadsorção Enzimática