Interleukin-10 delivered by mesenchymal stem cells attenuates experimental autoimmune myocarditis

Autoimmune myocarditis is characterized by over-activated immune system attacking the cardiomyocytes, resulting in heart function decline. In the current study, we investigated the therapeutic advantages of delivering Interleukin-10 (IL-10) by mesenchymal stem cells (MSCs), both of which had immune suppression functions, in treating experimental autoimmune myocarditis. The mouse model of autoimmune myocarditis was established by subcutaneous injection of troponin I in A/J mice. Mouse bone marrow derived mesenchymal stem cells (BM-MSCs) with or without IL-10 overexpression, or the recombinant IL-10 protein were delivered into the mice via tail-vein injection. The inflammation and fibrosis levels of the heart were evaluated with qPCR, ELISA and histological staining. Serum level of anti-troponin-I was assessed by ELISA. Heart function analysis was conducted with echocardiography. BM-MSCs overexpressing IL-10 had enhanced immune suppression functions. They also showed improved therapeutic effects from the perspective of heart function and cardiac fibrosis. The anti-troponin-I level was significantly reduced by MSCs overexpressing IL-10 when comparing with the MSCs or IL-10 protein injection. IL-10 delivered by MSCs showed therapeutic advantages in treating experimental autoimmune myocarditis.