人骨髓和脐带来源间充质干细胞向软骨细胞分化的实验研究

Experimental study on the differentiation of mesenchymal stem cells derived from human bone marrow and umbilical cord to chondrocytes

【目的】分离鉴定人骨髓间充质干细胞(human bone marrow mesenchymal stem cells,h BM-MSCs)和人脐带间充质干细胞(human umbilical cord-derived mesenchymal stem cells,hUC-MSCs),比较两种来源的间充质细胞体外分化为软骨细胞的能力。【方法】采用密度梯度离心或二型胶原酶消化方法分离提取人骨髓和脐带间充质干细胞培养并传代,流式细胞术检测间充质干细胞的表型CD34、CD45、CD73、CD105和CD271及Real-Time PCR方法检测成软骨分化的潜能。【结果】流式细胞术检测,与培养第3代的hUC-MSCs组相比,hBM-MSCs组的CD105和CD271表达水平明显升高;Real-Time PCR方法检测培养第3代的细胞向软骨细胞诱导分化后CollagenⅡm RNA的表达水平,hBM-MSCs分化组表达水平明显升高。【结论】成功分离人骨髓和脐带间充质干细胞,hBM-MSCs较h UC-MSCs有更强的向软骨细胞分化的能力,可以作为干细胞治疗软骨损伤的理想细胞来源。

【Objective】To isolate and identify human bone-marrow mesenchymal stem cells（h BM-MSCs） and human umbilical-cord mesenchymal stem cells（h UC-MSCs）, and compare the differentiation ability in vitro of these MSCs to chondrocytes.【Methods】MSCs derived from human bone marrow and umbilical cord were isolated and extracted via density-gradient centrifugation or type II collagenase digestion method, then cultured and passaged. The immunophenotypes of MSCs including CD34, CD45, CD73, CD105 and CD271 were detected via flow cytometry. The differentiation potential into chondrocytes was determined by real-time PCR.【Results】The results of flow cytometry showed that the expression levels of CD105 and CD271 in the h BM-MSCs group were obviously higher than those in the 3rd generation of h UC-MSCs group. The results of real-time PCR indicated that the m RNA expression level of collagen II in the h BM-MSCs differentiation group was significantly higher than that in the h UC-MSCs differentiation group.【Conclusion】MSCs can be successfully isolated from both human bone marrow and umbilical cord. The h BM-MSCs can be used as the ideal cell source of stem cells in the treatment for cartilage damage because they have stronger differentiation ability into chondrocytes than h UC-MSCs.