骨髓间充质干细胞移植治疗大鼠溃疡性结肠炎

背景：近年已有干细胞移植修复慢性肠炎受损组织的报道,但其治疗机制尚不明确。 目的：观察移植骨髓间充质干细胞在溃疡性结肠炎大鼠结肠的分布及分化情况,及对大鼠结肠黏膜的修复作用。 方法：取经鉴定的第3代大鼠骨髓间充质干细胞1×10⁶个,应用Hoechst 33342进行荧光标记,并将其经尾静脉移植入溃疡性结肠炎大鼠体内,分别于移植后3,7,14 d取材。 结果与结论：骨髓间充质干细胞移植后 3 d,大鼠结肠即可见荧光标记的细胞,移植后14 d,大鼠结肠荧光标记细胞仍较多,此时可见部分标记细胞表达细胞角蛋白。同时骨髓间充质干细胞移植后14 d,溃疡性结肠炎大鼠结肠黏膜白细胞介素10表达增高,肿瘤坏死因子α表达降低, 结肠黏膜的病理损伤明显好转。说明移植的骨髓间充质干细胞可迁移至结肠溃疡部位并分化为上皮细胞,同时可通过调节炎性因子的表达促进溃疡性结肠炎大鼠结肠黏膜损伤的修复。

Bone marrow mesenchymal stem cell transplantation for treating a rat model of ulcerative colitis

BACKGROUND:Recent studies have reported stem cell transplantation in repairing chronic enteritis-induced damaged tissue, but the therapeutic mechanism remains unclear. OBJECTIVE:To observe the distribution and differentiation of bone marrow mesenchymal stem cells (BMSCs) in the colon of ulcerative colitis rats, and the repair effect on rat colon mucosa. METHODS:1×10⁶ rat BMSCs at passage 3 were labeled by Hoechst 33342 fluorescence, and then implanted into the rats with ulcerative colitis via caudal vein. The specimen was collected at 3, 7 and 14 days following transplantation. RESULTS AND CONCLUSION:Fluorescently labeled BMSCs were visible in the colic mucosa of rats on day 3 following transplantation. On day 14, the number of BMSCs in the colon was abundant, and some cytokeratin-positive BMSCs could be seen in colon. At 14 days, interleukin-10 expression was increased, tumor necrosis factor alpha expression was reduced in the colon mucosa of rats with ulcerative colitis, and the pathological damage was obviously improved in the colon mucosa. These suggest that transplanted BMSCs could migrate to colonic ulcer site, differentiate into the epithelium, and promote the healing of injured colic mucosa in ulcerative colitis rats by regulating inflammatory factor expression.