The major causes of heart failure are myocarditis and its sequela, dilated cardiomyopathy (DCM).Experimental Autoimmune Myocarditis (EAM), an animal model of human giant cell myocarditis and DCM, may be elicited by immunization with cardiac myosin or cardiac myosin peptides.In the pathogenesis of EAM, cardiac fibroblast, dendritic cells and CD4 T cells are known to play variable roles.