The NOD transgenic HLA DQ8, H2-Ab1deficient mouse is diabetes resistant but develops cardiomyopathy resulting in early death from heart failure in both males and females. Histological exam indicates hearts are 3-4x larger than wildtype. Pathology results from an autoimmune response against normal cardiomyocytes in the atrial and ventricular walls, as well as against myocytes present in the outermost muscle layer surrounding the pulmonary veins. Disease progression can be blocked by cyclosporin A treatment and is accelerated with Complete Freund's Adjuvant (Elliott et al, 2003, PNAS) . This model is useful for studying autoimmune myocarditis, idiopathic dilated cardiomyopathy and heart failure and to understand the role of MHC class II in autoimmunity. The Jackson Laboratory 2024, used with permission.