PDCD1 and neoplasm: Other potential mechanisms include activation of quiescent alloreactive and effector memory T cells with ICI use illustrated by Dunlap et al; tumor and allograft antigen homology leading to the formation of cross-reactive T-cells as has been demonstrated in 2 cases of myocarditis but yet to be demonstrated in SOTR; and functional inhibition of regulatory T-cells via CTLA-4 and PD-1 inhibition [24–26].