CYTOKINE PRODUCTION PROFILE OF HEART-INFILTRATING T-CELLS IN CHAGAS-DISEASE CARDIOMYOPATHY

The hallmark of chronic Chagas' disease cardiomyopathy (CCC) is the fi nding of a T cell-rich inflammatory mononuclear cell infiltrate in the presence of extremely few parasites in the heart lesions. The scarcit y of parasites in affected heart tissue casts doubt on the direct part icipation of Trypanosoma cruzi in CCC heart tissue lesions, and sugges ts the possible involvement of autoimmunity. The cells in the infiltra te are presumably the ultimate effecters of tissue damage, and there i s evidence that such cells recognize cardiac myosin in molecular mimic ry with T. cruzi proteins rather than primary reactivity to T. cruzi a ntigens (Cunha-Neto et al. (1996) Journal of Clinical Investigation, 9 8: 1709-1712). Recently, we have studied heart-infiltrating T cells at the functional level. In this short review we summarize the studies a bout the role of cytokines in human and experimental T. cruzi infectio n, along with our data on heart-infiltrating T cells in human Chagas' cardiomyopathy. The bulk of evidence points to a significant productio n of IFN-gamma and TNF-alpha which may be linked to T. cruzi-induced I L-12 production.