表皮生长因子干预小鼠非黏附骨髓间充质干细胞成纤维细胞集落形成及向神经元样细胞的分化**

背景：非黏附骨髓间充质干细胞在体外可以不断形成成纤维细胞集落形成单位，并且可诱导分化为脂肪细胞、成骨细胞和软骨细胞，表现出一定的多分化潜能。 目的：探讨表皮生长因子对非黏附骨髓间充质干细胞形成成纤维细胞集落的影响，及其在体外向神经细胞分化的能力。 方法：分离小鼠双侧股骨、胫骨，全骨髓法分离总骨髓细胞，采用反复转移非黏附的骨髓细胞培养法纯化非黏附骨髓间充质干细胞。取第5代总骨髓细胞和非黏附骨髓间充质干细胞，加入含表皮生长因子、碱性成纤维细胞生长因子的神经细胞诱导液培养2周。观察非黏附骨髓细胞产生成纤维细胞集落形成单位的能力，表皮生长因子对成纤维细胞集落形成单位的影响，甲苯胺蓝和免疫细胞化学染色鉴定相关蛋白的表达。 结果与结论：总骨髓细胞、反复转移的非黏附骨髓间充质干细胞均能够不断产生成纤维细胞集落形成单位。给予表皮生长因子处理后，非黏附骨髓间充质干细胞成纤维细胞集落形成单位的效率明显增高。诱导2周后，免疫细胞化学染色显示，总骨髓细胞和非黏附骨髓间充质干细胞均表达神经细胞特异性蛋白NeuN和NF-200；经甲苯胺蓝染色在部分细胞中可见神经元特异性标记尼氏体。证实表皮生长因子可有效促进小鼠非黏附骨髓间充质干细胞形成成纤维细胞集落形成单位的效率，经反复转移的非黏附骨髓间充质干细胞能够诱导分化为神经细胞。

Epidermal growth factor interferes colony formation of fibroblasts and differentiation into neuron-like cells from non-adherent bone marrow mesenchymal stem cells in mice

BACKGROUND: Non-adherent mesenchymal stem cells (NA-MSCs) can form colony forming unit of fibroblasts and induce the differentiation into adipocytes, osteoblasts, and chondrocytes. OBJECTIVE: To determine the effect of epithelial growth factor (EGF) on colony formation of fibroblasts and differentiation into neuron-like cells from NA-MSCs. METHODS: Bilateral femur and tibia as well as total MSCs were separated, and repeated-transfer was employed to purify NA-MSCs. The fifth-passage total MSCs and NA-BMCs were induced in a medium containing EGF and basic fibroblast growth factor (b-FGF) for 2 weeks. Colony unit formation of fibroblasts, effect of EGF on colony-forming unit of fibroblasts, and relative protein expression detected by toluidine blue and immunocytochemical staining were observed. RESULTS AND CONCLUSION: Both total MSCs and NA-BMC could generate colony-forming unit of fibroblasts. After treatment of EGF, colony-forming unit of fibroblasts from NA-BMC was increased significantly. Immunocytochemical staining demonstrated that two weeks later both neuro-specific NeuN and NF-200 were observed in total MSCs and NA-BMC; while, toluidine blue staining indicated that neuron-specific Nissl body was observed in some cells. EGF can effectively promote colony-forming unit of fibroblast from NA-BMC, and repeated-transfer NA-BMC can induce differentiation into neuron-like cells.