脂肪间充质干细胞对兔扩张皮肤血管增殖影响的实验研究

ADSCs transplantation promotes the blood vessels proliferation of expanded skin using a tissue expansion model

目的在皮肤软组织扩张过程中,扩张皮瓣的成活很大程度取决于新生毛细血管的数量,文中探究脂肪间充质干细胞(adipose-derived stem cells,ADSCs)对扩张皮肤组织中新生毛细血管数量的影响。方法将20只新西兰大白兔随机数字表法分为实验组和对照组,每组10只。取兔的脂肪组织,体外分离、培养ADSCs,行免疫荧光细胞染色对其予以鉴定;在兔背部埋置一30 m L扩张器;在实验组扩张皮下注射lm L ADSCs悬液;对照组仅注射lm L等渗盐水作对照;4周后完成扩张;取扩张皮肤组织,行HE染色并观察毛细血管断面数量;用免疫组化染色检测血管内皮细胞标记物CD31和血管内皮生长因子(vascular endothelial growth factor,VEGF)表达情况,并对其微血管密度进行统计分析。用Elisa检测皮肤组织中VEGF的表达情况。结果 HE染色显示,实验组中毛细血管断面明显多于对照组;免疫组化染色显示,实验组CD31表达量增多,微血管密度实验组[(10.70±1.89)个/视野)]较对照组[(5.20±1.48)个/视野]明显增加(P<0.05);Elisa结果显示,与对照组相比,实验组VEGF的表达量较对照组增高[(215.46±24.19)pg/m L vs(300.27±23.40)pg/m L,P<0.05]。结论脂肪间充质干细胞能够促进扩张皮肤中新生血管生成,从而增加了对扩张皮肤的血液供应作用。

Objective In the process of skin soft tissue expansion,the survival of the expanded skin flap depends on the number of new capillaries. Therefore,this study aimed to explore the effect of adipose derived stem cells on the number of newborn capillaries in skin tissue expansion. Methods 20 New Zealand rabbits were randomly divided into experiment group and control group（ n = 10）. Adipose tissue was extracted from rabbit for isolation and culture of ADSCs in vitro,followed by flow cytometry and induced differentiation of epidermal cells. A 30 ml expander was embedded in the back of the rabbits. Subcutaneous injection of lm L ADSCs suspension was done on the rabbits of the experimental group,while the rabbits in control group were only injected with lm L isotonic saline. 4 weeks later,after the completion of skin expansion,the tissue was extracted,followed by HE staining to observe the capillary number and immunohistochemical staining to examine the expression of vascular endothelial cell marker CD31 and vascular endothelial growth factor（ VEGF）,and the statistic analysis of microvessel density. Elisa was used to detect VEGF expression in skin tissue. Results The results of HE staining showed there were more capillaries in experimental group than in control group.Immunohistochemical staining showed that the expression of CD31 in the experimental group was increased and the microvessel density in the experimental group（ 10. 70 ± 1. 89 / area） was significantly higher than that in the control group（ 5. 20 ± 1. 48 / area）（ P 〈0. 05）. Elisa results showed that the expression of VEGF increased in the experimental group（ [300. 27 ± 23. 40]pg / m L） compared with the control group（ [215. 46 ± 24. 19]pg / m L）（ P 〈0. 05）. Conclusion ADSCs can promote the angiogenesis in the expanded skin,thus increasing the blood supply and nutrition effect on expanded skin.