血小板衍生生长因子BB诱导骨髓间充质干细胞向血管内皮细胞分化

Platelet-derived growth factor BB induces bone marrow mesenchymal stem cells to differentiate into vascular endothelial cells

背景:关于血小板衍生生长因子BB促进骨髓间充质干细胞成血管的研究报道较少,而新生血管网提供的营养、生长因子和细胞因子对于骨组织生成具有至关重要的作用。目的:探讨血小板衍生生长因子BB诱导SD大鼠骨髓间充质干细胞向血管内皮细胞分化的效果。方法:①体外分离培养SD大鼠骨髓间充质干细胞,第3代细胞经流式鉴定其表面标记物CD45、CD29和CD34的表达,选用纯度较高的骨髓间充质干细胞进行血小板衍生生长因子BB干预实验;②第3代骨髓间充质干细胞经25μg/L血小板衍生生长因子BB诱导3 d,进行Matrigel基质胶细胞管腔形成实验,FITC-UEA-1和DIL-ac-LDL以及CD31免疫荧光染色鉴定,流式细胞术检测CD31的表达,最后采用RT-PCR检测血管内皮生长因子的mRNA水平。结果与结论:血小板衍生生长因子BB诱导后的细胞与Matrigel基质胶混匀接种后,可形成明显的管状结构;血小板衍生生长因子BB诱导后的细胞FITC-UEA-1和DIL-ac-LDL以及CD31表达均为阳性;血小板衍生生长因子BB诱导后细胞中血管内皮生长因子的mRNA表达均高于未诱导骨髓间充质干细胞(P <0.05)。结果表明,大鼠骨髓间充质干细胞经血小板衍生生长因子BB诱导后可以分化为具有功能的血管内皮细胞。

BACKGROUND:There are few reports about platelet-derived growth factor BB promoting angiogenesis of bone marrow mesenchymal stem cells.However,the nutrition,growth factors and cytokines provided by neovascular network play an important role in bone tissue formation.OBJECTIVE:To investigate the effects of platelet-derived growth factor-BB on the differentiation of bone marrow mesenchymal stem cells of Sprague-Dawley rats into vascular endothelial cells.METHODS:(1)Bone marrow mesenchymal stem cells of Sprague-Dawley rats were isolated and cultured in vitro.The surface markers CD45,CD29 and CD34 of the third generation were identified by flow cytometry.Bone marrow mesenchymal stem cells with high purity were selected for platelet-derived growth factor BB intervention experiments.(2)Passage 3 bone marrow mesenchymal stem cells were induced by 25μg/L platelet-derived growth factor BB for 3 days.Matrigel was selected for cell lumen formation experiments.The immunofluorescence method was used to detect the expression of FITC-UEA-1 and DIL-ac-LDL in cells to verify the fluorescence expression of CD31 in cells.Flow cytometry was used to detect the expression of CD31 in cells after induction.Finally,the mRNA level of vascular endothelial growth factor gene was detected by RT-PCR.RESULTS AND CONCLUSION:The cells were mixed with Matrigel and inoculated after platelet-derived growth factor BB induction.A clear tubular structure was formed;the expressions of FITC-UEA-1 and DIL-ac-LDL and CD31 expression were positive in bone marrow mesenchymal stem cells after induction.The expression of VEGF mRNA in platelet-derived growth factor BB-induced cells was higher than that in bone marrow mesenchymal stem cells without plateletderived growth factor BB(P<0.05).It is concluded that rat bone marrow mesenchymal stem cells can differentiate into functional vascular endothelial cells after being induced by platelet-derived growth factor BB.