中文摘要：

目的探讨肌内注射PNIPAM温敏水凝胶诱导小鼠骨骼肌慢性炎症的可行性。方法将PNIPAM或其与重组人骨骼肌C蛋白的混合物注入C57BL/6小鼠胫骨前肌（TA）,于注射后15、30及60 d分别检测TA肌内单核/巨嗜细胞渗出、肌肉自身抗原表达、MHC-I表达及肌内CD8^＋T细胞浸润。结果 PNIPAM温敏水凝胶可诱导TA肌内炎症持续达60 d,炎症反应的高峰出现于注射后30 d,随后逐渐减退。PNIPAM水凝胶与C蛋白混合液注射所诱发的肌内炎症较单纯的PNIPAM或C蛋白注射诱发的炎症反应更持久。免疫荧光分析证实,PNIPAM水凝胶注射后可见TA肌内出现CD8^＋T细胞浸润,部分新生肌纤维表达MHC-I。结论 PNIPAM温敏水凝胶肌内注射可诱导小鼠慢性骨骼肌损伤及炎症反应。

英文摘要：

In this study,we attempt to explore the possibility of the intramuscular implantation of the specific hydrogel to induce a chronic inflammatory-myoinjury model in mice.We injected temperature-sensitive PNIPAM hydrogel mixed with or without fast-type skeletal C protein into TA muscle of WT B6 mice,and analyzed mononuclear cell infiltration,muscle autoantigens expression,and the intramuscular CD8^＋ T cells infiltration and MHC-I expression on the surface of new myofiber in TA muscle on day 15,30 and 60 days post-injection.Data showed that PNIPAM hydrogel could induce a skeletal muscle inflammation during 2 months.The inflammation response in hydrogel injecting area reached a peak on day 30,and then gradually decreased.Interestingly,the mixture of PNIPAM hydrogel/C-protein initiated a more severe and persistent muscle inflammatory response,than hydrogel injection alone.Immunofluorecence analysis demonstrated that the hydrogel induced the chronic muscle inflammation featured by the CD8^＋ T cell infiltration and the increased class I MHC-positive regenerating myofibers.In conclusion,our work holds a new promise for preparing animal model of muscle inflammation using hydrogel as a bio-driver.And hydrogel-induced myositis model maybe useful for investigating pathologic mechanisms of muscle injury,inflammation and regeneration.