46P Abnormal gut microbiota may cause PD-1 inhibitor-related cardiotoxicity via suppressing regulatory T cells

The mechanism of PD-1 inhibitors-induced myocarditis in individuals with tumor is still unclear. Regulatory T cells (Treg) can directly inhibit T cell proliferation and activation, and also produce inhibitory cytokines with potent immunosuppressive properties. Deletion or aberrant function of Treg usually leads to autoimmune diseases. But reports on the role of Treg in PD-1 inhibitor-associated myocarditis are still very limited, and its role in the pathogenesis of myocarditis needs to be further explored.