“…Cardiac patients display a T-cell-mediated inflammatory response in situ (13,24,41), which is responsible for the pathology; this inflammatory profile is also observed in circulating activated T cells found at high frequencies in these patients (2,16,19,32). Although it is clear that a plethora of parasite and host factors influences the clinical outcome of Chagas' disease, recent studies have suggested that activation of functionally distinct Tcell populations in T. cruzi-infected individuals may be responsible for the establishment of different clinical forms (17,20). Thus, identifying these populations and the factors responsible for their activation will be critical for driving immune-based interventions to prevent pathology.…”