[Antigenic diversity of Plasmodium falciparum and serodiagnosis of tropical malaria].

The importance of antigenic diversity in immunogenicity of population of P. falciparum was studied in regard of immunodiagnosis of tropical malaria. The sera from 42 adult non-immune persons with confirmed infection by P. falciparum and from 30 persons from Africa with confirmed infection by P. falciparum were examined with three antigens differing in geographic origin. Antigen A2 Gambia, M94 Thailand, FCQ2 Papua New Guinea were checked. The following results were obtained: 1) In the quantity of polyclonal antibodies detected higher frequency of higher titres and higher GMRT (statistically significant differences) were demonstrated with three antigens in the persons from the endemic areas of malaria. 2) Higher variation (antigenic diversity) in the quantity of polyclonal antibodies (difference up to 6 dilutions) in the non-immune population in contrast to semi-immune population where the differences were only at the level of two fold dilutions. 3) The correspondence of titres of polyclonal antibodies to all three geographically different antigens was statistically significantly (P less than 0.05) more frequent in the sera of semi-immune persons in contrast to non-immune individuals. 4) The results have shown that repeated infections in endemic areas of malaria with antigenically diverse strains induce the formation of polyclonal antibodies against all antigenic varieties and are better detectable by antigen of any antigenic variety.(ABSTRACT TRUNCATED AT 250 WORDS)