Association of the IgG response to Plasmodium falciparum merozoite protein (C-terminal 19 kD) with clinical immunity to malaria in the Brazilian Amazon region.
The antibody response to the C-terminal 19-kD fragment of Plasmodium falciparum merozoite surface protein-1 (PfMSP1-19) was investigated in groups of subjects living in areas of Brazil with different levels of malaria transmission. The prevalence and the levels of IgG to PfMSP1-19 increased with the time of exposure and were positively correlated with the absence of clinical symptoms in parasitemic patients. The frequency of positive response and the mean level of IgG were higher in areas where malaria prevalence was more intense, especially among asymptomatic patients. The serum absorbance values of the IgG1 isotype were significantly higher among subjects with long-term exposure and in asymptomatic infections. These data suggest a protective role of IgG1 in naturally acquired immunity in spite of the unstable transmission levels in the Brazilian Amazon.
Departamento de Parasitologia, Universidade Federal de Minas Gerais; Belo Horizonte, Brazil. embraga@icb.ufmg.br
Erika Martins
EM
Braga
Rosa Maria
RM
Barros
Tânia Afonso
TA
Reis
Cor Jesus F
CJ
Fontes
Cristiane Guimarães
CG
Morais
Maria Sĵnia
MS
Martins
Antoniana Ursine
AU
Krettli
D000328:Adult; D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood*; D000917:Antibody Formation; D001938:Brazil; D005260:Female; D006801:Humans; D007113:Immunity, Innate / Q000276:immunology*; D007074:Immunoglobulin G / Q000276:immunology*; D007132:Immunoglobulin Isotypes / Q000097:blood; D016778:Malaria, Falciparum / Q000276:immunology*; D008297:Male; D020066:Merozoite Surface Protein 1 / Q000276:immunology*; D010963:Plasmodium falciparum / Q000276:immunology*; D010966:Plasmodium vivax / Q000276:immunology
D000913:Antibodies, Protozoan; D007074:Immunoglobulin G; D007132:Immunoglobulin Isotypes; D020066:Merozoite Surface Protein 1