骨髓间充质干细胞移植对结肠吻合口愈合的影响

摘要

背景：骨髓间充质干细胞具有很大的增殖能力、多向分化潜能、向损伤组织定位修复的功能、低免疫原性和免疫调节作用，其可以用来治疗传统治疗方案难以治愈的疾病，具有广阔临床应用价值，成为细胞移植治疗的新热点。　　目的：观察局部注射的骨髓间充质干细胞在缺血性结肠吻合模型大鼠肠黏膜的定植情况及对结肠吻合口愈合的影响。　　方法：将40只雌性SD大鼠随机分为4组：对照4 d组和对照7 d组，行左侧结肠缺血性吻合后肠黏膜下局部注射0.5 mL胎牛血清，骨髓间充质干细胞移植4 d组和骨髓间充质干细胞移植7 d组，行左侧结肠缺血性吻合后，取培养至第3代的骨髓间充质干细胞(0.5 mL，1×107个细胞)直接在肠黏膜下注射移植。分别测定各组大　　结果与结论：骨髓间充质干细胞移植组吻合口爆破压、羟脯氨酸含量较对照组明显增高，组织病理学评分提示除上皮形成及炎症指标外，黏膜坏死、胶原蛋白沉积量、成纤维细胞活性及新生血管形成指标骨髓间充质干细胞移植组优于对照组。结果表明移植同种异体大鼠骨髓间充质干细胞可在受体缺血性结肠吻合模型肠道内定植，并可加速结肠吻合口的愈合，其发挥疗效主要是通过旁分泌的形式促进机体内源性修复，而骨髓间充质干细胞直接分化为肠黏膜上皮细胞作用较小。　　鼠吻合口爆破压，取吻合口处肠管行羟脯氨酸含量测定，苏木精-伊红染色及Masson染色行组织病理学评分， Y 染色体原位杂交检测供鼠来源的细胞迁徙及定植情况。%BACKGROUND:With the advantage of strong proliferation ability, multi-directional differentiation potential, fuly repair of damaged tissue, low immunogenicity and immune regulation, bone marrow mesenchymal stem cels can be used to treat refractory diseases which are difficult to cure by the traditional methods. Its immeasurable clinical application value makes it the new hot spots of cel transplantation therapy. OBJECTIVE:To observe the colonization of bone marrow mesenchymal stem cels in intestinal submucosa and healing effects after local injecting bone marrow mesenchymal stem cels into rat models of ischemic colon anastomosis. METHODS:Forty female Sprague-Dawley rats were randomly divided into four groups: group A (postoperative 4 days, control group), group B (postoperative 7 days, control group), group C (postoperative 4 days, bone marrow mesenchymal stem cels group), group C (postoperative 7 days, bone marrow mesenchymal stem cels group). In group A and group B, 0.5 mL fetal bovine serum was injected into the line of the left colon ischemic bowel mucosa after anastomosis. Similarly, about 1×107 cels suspended in 0.5 mL sterile physical serum were submucosaly injected into the left colon ischemic bowel mucosa in group C and group D. Rat anastomotic bursting pressure and hydroxyproline content were detected respectively. The migration and engraftment of donor derived bone marrow mesenchymal stem cels was detected by Y chromosomein situ hybridization in colon tissue. Histopathological observation was scored though hematoxylin-eosin and Masson staining. RESULTS AND CONCLUSION: Bone marrow mesenchymal stem cels transplantation augmented bursting pressure and hydroxyproline content at the site of ischemic colonic anastomosis. The histopathological features, except for the epithelization and inflammation, were significantly more favorable in the bone marrow mesenchymal stem cel groups, and the microvascular density was significantly higher than that in the control groups. These findings indicate that alogeneic bone marrow mesenchymal stem cels can be colonized in the receptor of ischemic colon anastomosis model, and significantly accelerate the recovery of ischemic colonic anastomosis. It contributes to the healing of ischemic colonic anastomosis through the paracrine activities of bone marrow mesenchymal stem cels, rather than direct differentiation.