GPR15 and myocarditis: In myocarditis, GPR15 deficiency leads to delayed migration of Treg cells to the infected myocardium, resulting in inflammatory-induced cardiac injury from day 7 p.i. In addition, expression of Ifnγ was delayed in LV tissue of GPR15-deficient mice, which might lead to ongoing virus replication in the early phase of myocarditis and, thus, virus persistence later.