Distinct patterns of blood-stage parasite antigens detected by plasma IgG subclasses from individuals with different level of exposure to Plasmodium falciparum infections

Background In endemic regions naturally acquired immunity against Plasmodium falciparum develops as a function of age and exposure to parasite infections and is known to be mediated by IgG. The targets of protective antibodies remain to be fully defined. Several immunoepidemiological studies have indicated an association of cytophilic anti-parasite IgG with protection against malaria. It has been hypothesized that the initial antibody responses against parasite antigens upon first few Plasmodium falciparum infections is dominated by non-protective IgG2/IgG4 and IgM antibodies, which then gradually develop into protective response dominated by cytophilic IgG1 and IgG3 antibodies.