骨髓基质细胞体外分离培养和分化为

摘要 目的：观察体外培养大鼠骨髓基质细胞（BMSCs bone marrow stromal cells）的生物学特性并探讨其分化为Schwann细胞表达S100的机制，为组织工程学修复周围神经损伤奠定一定的实验基础。方法：从成年SD大鼠的股骨和胫骨中分离培养BMSCs，倒置显微镜下动态观察细胞的生长状态，采用MTT法检测细胞的活力，FCM检测细胞周期等方法研究BMSCs的生物学特性。应用复合诱导因子（BME, RA ,FSK, bFGF, PDGF, HRG）体外诱导BMSCs向Schwann细胞分化。诱导分化后采用免疫荧光细胞化学染色，流式细胞仪，逆转录PCR方法分别检测检测胶质细胞标记蛋白S100蛋白和mRNA的表达。结果：BMSCs在体外容易扩增，传1－8代以内的细胞增殖能力无明显变化。未经诱导的BMSCs大部分处于G0和G1期。诱导分化后的细胞形态上类似Schwann细胞，并且表达胶质细胞的标记蛋白S100蛋白及其mRNA明显升高。结论：BMSCs在体外可以向类Schwann细胞诱导分化，并且表达胶质细胞的标记蛋白S-100蛋白及其mRNA。

Rat bone marrow stromal cells differentiate into S100-positive Schwann cell-like cells in vitro induction

We examined the expression of of S100 protein, the maker of Schwann cells (SC), during rat bone marrow stromal cells (MSCs) differentiate into Schwann cell (SC)-like cells in vitro conditional induction. We isolated MSCs from adult Sprague-Dawley rat bone marrow and characterized cell vitality by MTT method, CD markers and cell cycle by flow cytometry. Then MSCs were induced to differentiate into SC cells under special conditions in culture. Induced MSCs were detected S100 protein, glial fibrillary acidicprotein (GFAP) and low-affinity nerve growth factor receptor (p75) by immunofluorescent staining. Furthermore, S100 protein and mRNA level were evaluated during the induction by flow cytometry, Western blot and RT-PCR. The vast majority of MSCs were standing at the G0/G1 phase of the cell cycle. After induction, MSCs showed morphological changes into cells resembling SC and immunoreactivity to SC surface markers. The S100 level also increased with the duration of the induction. MSCs can differentiate into SC-like cells through conditional induction and grow more matured along with the duration of the induction. Our results demonstrate that MSCs can be a candidate for tissue engineering.