Immunology of Chagas' disease

In the circulation of patients large amounts of IgM and IgGcan be detected which:

lyse insect parasites (metacyclic epimastigotes) and thus protect against superinfection,
do not lyse trypomastigotes (blood forms)
have no effect on the intracellular amastigotes

The actively dividing parasite itself hides away inside the host cells and cannot be reached by the immune system.

A major problem is the development of autoimmune disease:

T.cruzi amastigotes and neuronal cells share common antigenic determinants: the recognition of the parasite epitpes leads to the recognition of self which provokes an autoimmune disease that affects nerve cells and muscle cells.

Vaccines:

Since the antigens responsible for the onset of autoimmune disease have not yet been characterized it is impossible to develop vaccins based on whole organisms, since any such vaccin may provoke the same kind of autoimmune disease without ever having been in contact with the parasite. Therefore, the only solution would be the development of so-called subunit vaccins (see malaria).

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Last updated: 22 October 1997.

created by :Fred Opperdoes