PRESENCE OF CELLS PRODUCING ANTIHEART AUTOANTIBODIES IN THE INFLAMMATORY INFILTRATE OF CHRONIC CHAGASIC MYOCARDITIS

Chagasic myocarditis is associated with the appearance of circulating antiheart autoantibodies. In order to find out if there was local synthesis of those antibodies we investigated, by means of a solid immunoenzymatic technique, the presence of cells secreting antibody (ASC) against syngeneic soluble heart antigens in the mononuclear cell (MNC) population isolated from the hearts of mice chronically infected with Trypanosoma cruzi. In seven animals the number of ASC ranged between 300 and 2080 per 106 MNC. A similar number of cells was observed when the assay was carried out with T. cruzi-soluble antigens. When the ASC were enumerated in an assay simultaneously with both antigens, their number doubled that found in the single antigen assay, suggesting that there was no cross-reactivity between the heart and the parasite antigens. These results indicate that some of the cells in the inflammatory infiltrate of chronic chagasic myocarditis synthesize IgG autoantibodies against heart antigens, a phenomenon which may lead to a local concentration of antibody large enough to induce tissue damage. © 1991.