IgGl and IgG2 antibody responses to Plasmodium falciparum

In Manarintsoa, near Antananarivo, Madagascar, two groups of patients were defined in terms of malaria clinical immune status: Group MA+ consisted of 36 patients who suffered from between one to four malaria attacks (MA) during the 20-week study, and Group MAwho comprised of 48 persons who did not have any malaria attacks during this time. In group MA+, IgM and IgG antibody levels to Plasmodium fulciparum exoantigens (E-Ag) were inversely related to the number of malaria attacks. The level of IgM antibodies were significantly higher in group MA+. In contrast, IgG, IgGl, IgG2, IgG3 and IgG4 antibodies to E-Ag were significantly higher in group MA-. The level of IgGl antibodies was inversely correlated, and IgG2 antibodies were positively correlated to the number of malaria attacks.