TNNI3 and myocarditis: Excitingly, Dpep2fl/fl LyzM-Cre+ mice exhibited more severe myocarditis than the control mice (Dpep2fl/fl) as shown by the aggravated cardiac inflammation (Figure 2C), weaker left ventricular systolic function (Figure 2D), higher cTnI activity (Figure 2E) as well as much more abundant pro-inflammatory cytokine production (Figures 3A,B).