Induction of Murine Models of Autoimmune Myocarditis, Valvulitis, and Cardiomyopathy

Myocarditis and valvulitis are inflammatory diseases affecting myocardium and heart valves. Myocarditis, a viral-induced disease of myocardium, may lead to dilated cardiomyopathy and loss of heart function, and valvulitis leads to deformed heart valves and altered blood flow in rheumatic heart disease. Animal models recapitulating these diseases are important for understanding the human conditions. Cardiac myosin is a major autoantigen in heart tissue, and antibodies and T cells to cardiac myosin are evident in inflammatory heart diseases. This article is a practical guide to the induction and evaluation of experimental autoimmune myocarditis (EAM) in several mouse strains and the Lewis rat. Purification protocols for cardiac myosin and protocols for the induction of EAM by cardiac myosin and its myocarditis-producing peptides, as well as coxsackievirus B3 (CVB3), are defined. Protocols for assessment of myocarditis and valvulitis in humans and animal models provide methods to define functional autoantibodies targeting cardiac myosin, β-adrenergic, and muscarinic receptors, and their deposition in tissues. © 2026 Wiley Periodicals LLC. Basic Protocol 1: Induction of EAM in mice by active immunization with cardiac myosin Alternate Protocol: Induction of EAM in mice by adoptive transfer of cardiac-myosin-stimulated T cells Basic Protocol 2: Induction of EAM in rats by active immunization with cardiac myosin Support Protocol 1: Purification of cardiac myosin Support Protocol 2: Preparation of antigen/adjuvant emulsion by agitation for EAM induction in mice and rats Support Protocol 3: Collection and histopathological assessment of mouse or rat hearts Support Protocol 4: Immunostaining of rat heart tissue or cells for deposited antibody Basic Protocol 3: Induction of myocarditis in mice by inoculation with coxsackievirus B3 (CVB3) from infectious cDNA clones Basic Protocol 4: Induction of myocarditis and dilated cardiomyopathy in mice by inoculation with heart-passaged coxsackievirus B3 (CVB3) Basic Protocol 5: Induction of autoimmune valvular heart disease by inoculation with recombinant streptococcal M protein Basic Protocol 6: Protein kinase A (PKA) assay of serum antibody signaling of the β-adrenergic receptor with subsequent activation of PKA Basic Protocol 7: Measurement of serum antibody titers against human cardiac myosin, human adrenergic β₁ and β₂ receptors, and muscarinic 2 receptor Basic Protocol 8: Detection of antibodies against human cardiac myosin peptides in human serum.