Sera from Cameroon recognize proteins of Plasmodium falciparum isolates from geographically diverse areas of the world

Abstract
Immunological reactions of clinically-defined sera collected from 176 children and adults (3 to 63 years of age) living in malaria endemic regions of Cameroon were evaluated by ELISA, growth inhibition studies and immunoprecipitation assays using different parasite isolates from geographically diverse areas. The proportions of sera positive by ELISA and with positive growth inhibitory activity tended to increase with increased age. SDS-PAGE analyses of immunoprecipitates using [35S]methionine labelled parasite polypeptides revealed that a wide range of proteins was recognized by the sera. There were many similarities in the patterns of antigens immunoprecipitated in the different isolates, particularly when immune sera were used. Variability in response was more evident in sera collected from children. These findings suggest that strains may share components which generate protective immunity.