体外扩增过程中人骨髓间充质干细胞的增殖与分化规律

目的：系统考察体外扩增过程中人骨髓间充质干细胞（MSC）的增殖与分化规律，为MSC任组织修复以及细胞治疗中的应用提供参考、方法：以全骨髓贴壁法分离成人肋骨骨髓MSC，在相同条件下分别考察各代细胞形态、生长、表面标记、细胞周期、成骨、成软骨及成脂肪能力的变化情况。结果：随代次增加，MSC增殖能力、成骨、成脂肪能力均有所下降，而成软骨能力无明显降低；成骨、成软骨及成脂肪能乃均保持到细胞衰老。存扩增过程中，MSC始终保持较高的纯度，CD29、CD44、CD105的阳性率均在90％以上，CD14、CD34和CD45的阳性率均在4％以下、结论：在体外培养过程中MSC干细胞特性逐渐丢失，其中向骨、脂肪方向的分化潜能较软骨方向更易失去；而多向分化能力的保持较之自我更新能力更为持久。MSC在7代以前可作为基础研究及临床应用的良好对象。

Proliferation and differentiation characteristics of human bone marrow mesenchymal stem cells during ex-vivo expansion

AIM: To investigate the effects of ex-vivo expansion on proliferative ability, pluripotentiality and other biologic characteristics of human bone marrow mesenchymal stem cells(MSCs). METHODS: MSCs were isolated from human costal bone and passaged under the same culture conditions. At each passage, the characteristics of proliferation kinetics, osteogenic, chondrogenic, adipogenic differentiation potential were analyzed, and cell morphology, surface markers and cell cycle were investigated as well. RESULTS: The proliferative ability and osteogenic, adipogenic differentiation potential decreased during culture expansion, while chondrogenic differentiation potential had no significant changes. MSCs maintained their multiple differentiation potential during their life-span. For each passage, the positive ratio of CD29, CD44, CD105 were all above 90% and the negative ratio of CD14, CD34, CD45 were below 4%. CONCLUSION: Culture expansion causes MSCs to gradually lose their stem cell properties. During ex-vivo expansion of hMSCs, the osteogenic and adipogenic differentiation potential are more likely to lose than chondrogenic differentiation potential. Multiple differentiation potential is conserved longer than self-renewal capacity. MSCs before 7th passage can be a valuable subject for basic research and clinical application.