Parasitic Infection and Autoimmunity

Parasitic infections are accompanied by the activation of autoimmune mechanisms. The latter include molecular mimicry between parasitic polypeptides and host antigens, the alteration of host antigens, the polyclonal activation of B cells, and the manipulation of the idiotypic networks. Protozoan diseases, such as malaria, leishmaniasis, schistosomiasis and onchocerciasis are associated with the generation of a wide spectrum of autoantibodies and are associated with autoimmune haemolytic anaemia, nephritis, autoimmune hepatitis and other clinical and laboratory autoimmune phenomena. Infestation with multicellular parasites, such as helminthes, can also lead to an immunomodulatory effect mediated by regulatory T cells and might suppress autoimmunity.