The experimental research of autoimmune myocarditis induced by immunization of mice with LCWE

Objective: To establish an animal model of autoimmune myocarditis induced by Lactobacillus casei cell wall element (LCWE). Methods: LCWE was preparated and diluted to 1 mg/ml. Then it was used for immunization of genetically predisposed mice to establish animal model of autoimmune myocarditis. Results: Fourteen day after the first immunization with LCWE, all BALB/c mice developed histological myocarditis with pathological features of myoendocarditis and myoepicarditis like infiltration of lymphocyte, local myocardial necrosis and local bleed in myocardium. EM microscopy showed myocardial cell intumescence, mitochondria intumescence, muscle fibers melt and infiltration of lymphocyte. A high titer of myosin-specific autoantibodies(IgG) and more lymphocytes were detected in immunized mice. On the 28th day after the first immunization with LCWE, the inflammation and myocardial necrosis were not severe, a same titer of myosin-specific autoantibodies(IgG) and less lymphocyte were detected in immunized mice. Conclusion: Autoimmune myocarditis can been induced by immunization of mice with LCWE, pathological changes were typical, the morbidity meets the requirement of research.