干酪乳杆菌细胞壁成分诱导小鼠自身免疫性心肌炎的研究

目的探讨应用干酪乳杆菌细胞壁成分(Lactobacillus casei cell wall element，ICWE)诱导小鼠自身免疫性心肌炎的可能性。方法参考Trang等“0的方法制备成浓度为1mg/ml的LCWE。以此LCWE免疫遗传易感的BALB／c小鼠，建立自身免疫性心肌炎的模型。结果全部实验组小鼠在初次免疫后第14天出现不同程度的心肌炎病理改变，光镜下主要表现为心肌间质淋巴细胞浸润，局灶性心肌坏死和局灶性出血，并同时存在心内膜炎和心外膜炎。电镜下见心肌细胞及线粒体肿胀、肌丝溶解和淋巴细胞浸润。免疫鼠脾脏淋巴细胞升高，血清出现较高滴度的抗心肌抗体。在初次免疫后第28天上述炎症及心肌坏死减轻，脾脏淋巴细胞较前下降，血清抗心肌抗体滴度较前无明显变化。结论用LCWE能够诱导小鼠产生自身免疫性心肌炎，该动物模型病理改变典型，群体发生率高。

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 Autoinmune myocarditis can been induced by immunization of mice with LCWE, pathological changes were typical, the morbidity meets the requirement of research.