Flk-1^+间充质干细胞和SP细胞参与肠道损伤修复的比较

Repair of intestinal irradiation injury by Flk-1^+ MSCs and SP cells

目的比较骨髓来源Flk-1+间充质干细胞和肠道上皮来源的SP细胞生物学特征及参与肠道放射性损伤修复的潜能及机制。方法流式细胞仪分析免疫表型;在肠道放射性损伤小鼠模型中,观察移植细胞的分布、分化及各组受体鼠照射后组织病理学改变及长期纤维化情况。结果这两个干细胞亚群的免疫学表型存在很大的差异;在肠道放射性损伤模型中均能够快速归巢到损伤的肠道局部,参与肠道上皮细胞的损伤修复,减轻照射后引起的纤维化胶原沉积。SP细胞移植后主要分布在肠道上皮,而Flk-1+间充质干细胞除了分布在肠道上皮外,还参与肠道间质的修复。结论骨髓来源Flk-1+间充质干细胞和肠道上皮来源的SP细胞都能有效的参与肠道放射性损伤修复,但修复机制上有差异。

Objective Comparing biological characteristics and the roles in repairing of intestinal irradiation injury of bone marrow derived Flk-1＋ MSCs and small intestinal derived SP cells. Methods Phenotypes of the two cell population were determined by flow cytometery. Flk-1＋ MSCs and intestinal SP cells were infused into irradiated mice, distribution and differentiation of these cells were determined. Histopathological change and fibrosis were e- valuated. Results The phenotypes of Flk-1 ~ MSCs and intestinal SP cells were quite different. Both Flk-1 ~ MSCs and intestinal SP cells could home to injury tissue rapidly, participate intestinal epithelial repair, and alleviate fi- brosis and collagen deposition after irradiation. SP cells mostly engrafted into intestinal epithelium, while Flk-1＋ MSCs partly engrafted into interstitial region as well as epithelium. Conclusion Flk-1＋ MSCs and intestinal SP cells may alleviate symptoms effectively, though their mechanisms are disparite.