Acquired immune responses to the N- and C-terminal regions of Plasmodium vivax merozoite surface protein 1 in individuals exposed to malaria

• Autor(a) principal: Soares, Irene S
• Data de Publicação: 1997
• Outros Autores: Levitus, Gabriela, Saouza, José Maria de, Del Portillo, Hernando A, Rodrigues, Mauricio M
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Digital do Instituto Evandro Chagas (Patuá)
• Texto Completo: https://patua.iec.gov.br/handle/iec/3568
• topic: Malária Vivax; Proteína 1 de Superfície de Merozoito; Plasmodium vivax; Precursores de Proteínas; Escherichia coli; Estudos Soroepidemiológicos; Ensaio de Imunoadsorção Enzimática

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.