人胚腱细胞转化生长因子-β受体Ⅰ、Ⅱ、Ⅲ密度分析

Assay of the density of transforming growth factor-β receptor Ⅰ,Ⅱand Ⅲ in human tenocytes

目的 观察转化生长因子-β受体I 、II和III （TβRI 、II 、III）在体外培养的肌腱细胞中的表达情况，探讨TGF-β1对细胞周期及增殖指数PI值的影响。方法 采用免疫组化法鉴定受体的表达，流式细胞仪法分析了同一细胞周期不同亚时相的TβRI 、II 、III受体数目差别并观察了不同浓度的TGF-β1对细胞周期及增殖指数PI值(S+G2M)的影响。结果 TβRI 、II 、III在体外培养的肌腱细胞中均有表达，TβR I 、II 、III平均荧光强度在G1期分别是7.93±0.20、8.76±0.16、8.46±0.14，而在G2M期分别是17.7±0.36、18.9±0.35、18.3±0.67。细胞周期分析表明：TGF-β1作用下，G0/G1%呈降低趋势，而S%呈升高趋势，反映细胞增殖活力的PI值也呈升高趋势，尤以5 ng/ml 以上浓度时为显著(P<0.05)。结论 在肌腱细胞周期的不同亚时相，肌腱细胞TβRI 、II 、III各自密度均具显著差别（P<0.01），TGF-β1能促进腱细胞增殖。TGF-β受体系统不同亚时相的差别可能是其调控细胞增殖活动的生物学基础。

： Objective To investigate the expression of transforming growth factor (TGF)-β receptor Ⅰ,Ⅱand Ⅲ (TβRⅠ,Ⅱ, Ⅲ) in human tenocytes in vitro and observe the effects of TGF -β1 on the cell cycle and the proliferation indexes (PIs) of the tenocytes. Methods The expressions of TβRⅠ,Ⅱ,Ⅲ in the tenocytes cultured in vitro were determined immunihistochemically, and double staining with propidium iodide (PI) and fluorescein isothiocyanate (FITC) was employed to assess the densities of TβRⅠ,Ⅱand Ⅲ in various phases of cell cycle which were measured by flow cytometry. Likewise, flow cytometry was also uesd to assess the effects of TGF -β1 on the cell cycle of the tenocytes. Results The expressions of TβRⅠ,Ⅱand Ⅲ were all observed in the tenocytes. The mean fluorescence intensity of TβRⅠ, TβRⅡ and TβRⅢ in G1 phase was 7.93±0.20, 8.76±0.16, 8.46±0.14 and 17.7±0.36, 18.9±0.35, 18.3±0.67 in G2M phase respectively, showing significant difference between the 2 phases（P<0.01）. TGF-β1, especially at the concentration over 5 ng/ml, significantly increased the percentage of cells in S phase and the PIs. Conclusion These results indicate that the ratio of TβR Ⅰ,Ⅱand Ⅲ levels varies with the ongoing cell cycle, which might be involved in promoting cell proliferation.