移植dMSCs向放创复合伤创面优势分布的机制研究

Study on mechanisms of preferential distribution of the transplanted dermal multipotent stem cells in rats with combined radiation and wound injury

目的探讨静脉输注的真皮多能干细胞(dermal multipotent stemcells,dMSCs)向放创复合伤大鼠创面优势分布的机制。方法RT-PCR和免疫组织化学检测创面中基质细胞源性细胞因子(stromal-dereivedfactor-1,SDF-1)的表达水平,以及dMSCs中SDF-1受体CXCR4的表达水平。Transwell培养体系中,观察SDF-1对dMSCs的趋化作用。结果放创复合伤大鼠创面SDF-1的表达水平明显高于正常大鼠,同时dMSCs表达CXCR4。体外趋化实验发现,SDF-1对dMSCs有很强的趋化作用,而使用SDF-1的中和性抗体后,放创复合伤大鼠伤口液对dMSCs的趋化作用明显下降(P<0·05)。结论放创复合伤大鼠创面上调表达的SDF-1在移植dMSCs向创面的优势分布中有重要作用。

Objective To explore the mechanisms of preferential distribution of transplanted dermal muhipotent stem cells （dMSCs） to surface of wound in rats with combined radiation and wound injury （CRWI）. Methods The expression of stromal-dereived factor-1 （SDF-1 ） in wounds of rats and the expression of CXCR4 （the only known receptor of SDF-1） in dMSCs were examined using RT-PCR and immunohistochemistry. The chemotactic effect of SDF-1 on dMSCs was evaluated in Transwell culture system. Results The expression of SDF-1 in wound of CRWI rats was upregulated significantly compared with the normal rats＇skin, dMSCs expressed CXCR4. SDF-1 had a strong chemotactic effect on dMSCs： the chemotactic effect of wound extracts from CRWI rats was significantly reduced （ P〈0.05 ） when neutralized antibody to SDF-1 was added. Conclusion The upregulated expression of SDF-1 played an important role in the preferential distribution of transplanted dMSCs to wound in rats with CRWI.