β射线照射皮肤损伤创面注射骨髓间充质干细胞后的创面愈合

背景：β射线皮肤损伤创面难愈，尚无有效的治疗方法。 目的：观察骨髓间充质干细胞对β射线皮肤损伤创面愈合的影响。 方法：①选用SD雌性大鼠3只分离培养骨髓间充质干细胞，传代细胞生长至第5代，DAPI标记细胞，制备骨髓间充质干细胞悬液。②选3月龄清洁级SD雌性大鼠47只，随机分为3组：治疗组应用直线加速器产生的β射线(45 Gy)单次照射大鼠臀部皮肤40 mm×30 mm，建立急性深Ⅱ度β射线皮肤损伤动物模型，创面出现后将骨髓间充质干细胞悬液注入大鼠创面皮下及真皮层；对照组β射线照射同治疗组，创面出现后注射安慰剂，用法同治疗组。正常组为正常大鼠。光镜下观察治疗后1，2，3，4周各组大鼠创面组织病理学变化，免疫组织化学方法检测CD31、CK4、成纤维细胞生长因子含量的动态变化。 结果与结论：治疗组创面愈合时间比对照组明显加快(P < 0.05)。治疗组注射骨髓间充质干细胞细胞悬液后1-4周CD31、CK4、成纤维细胞生长因子阳性细胞值明显高于对照组(P < 0.05)。证实骨髓间充质干细胞能促进β射线皮肤损伤创面的愈合，缩短创面愈合的时间。

Bone marrow mesenchymal stem cell injection for treatment of β-ray-irradiated skin injury in rats

BACKGROUND:The β-ray-irradiated skin injury is difficult to heal and there is no effective treatment method for β-ray-irradiated skin injury. OBJECTIVE:To investigate the effect of bone marrow mesenchymal stem cell transplantation in treatment of β-ray-irradiated skin injury in rats. METHODS:Three Sprague-Dawley female rats were killed to isolate and culture the bone marrow mesenchymal stem cells, then the cells were labeled with 4',6-diamidino-2-phenylindole to prepare the bone marrow mesenchymal stem cells suspension after passaged to the fifth generation. Forty-seven Sprague- Dawley female rats of 3 months old and clean grade were randomly divided into three groups: treatment group, control group, and normal group. In the treatment group, single dosage (45 Gy) of β-ray irradiation produced by linear accelerator was applied on buttock skin (40 mm×30 mm) in rats, and the acute deep Ⅱ β-ray-irradiated skin injury model was established. Bone marrow mesenchymal stem cell suspension was injected in the subcutaneous and dermal layers after the wound appeared. The rats in the control group were irradiated as those in the treatment group, and placebo was injected when the wound appeared, with the same method as the treatment group. Rats in the normal group were not irradiated. The pathological changes of wound tissue of rats in each group were observed at 1, 2, 3 and 4 weeks after treatment under light microscope, and the concentration of CD31, CK4 and fibroblast growth factor was detected by immunohistochemistry. RESULTS AND CONCLUSION:The wound healing time in the treatment group was shorter than that in the control group (P < 0.05). Immunohistochemistry showed the number of CD31, CK4 and fibroblast growth factor positive cells in the treatment group at 1-4 weeks after bone mesenchymal stem cell suspension injection was significantly greater than that in the control group (P < 0.05). It indicates that bone mesenchymal stem cell injection can promote the wound healing of β-ray-irradiated skin injury and reduce wound healing time.