目的探讨整合素-β1在层黏连蛋白(LN)促进施万细胞(SCs)合成细胞外基质(ECM)过程中的作用。方法体外培养10只SD大鼠来源的SCs,经外源性LN处理后,双重免疫荧光细胞化学法检测LN和整合素-β1的表达情况,免疫印迹法检测SCs内黏着斑激酶(FAK)的磷酸化水平。用抗体Ha2/5封闭细胞表面受体整合素-β1,再经外源性LN处理后,免疫印迹法检测FAK的磷酸化水平变化,免疫荧光细胞化学法检测SCs合成LN、着位素、Ⅳ型胶原等ECM成分的变化。结果经外源性LN处理后,SCs内LN和整合素-β1均有阳性免疫反应,且局部共表达,SCs内FAK的磷酸化水平增加。封闭细胞表面受体整合素-β1后,SCs内FAK的磷酸化水平明显下降,SCs内LN、着位素、Ⅳ型胶原等ECM成分的表达和分布未见明显改变。结论LN能与SCs表面受体整合素-β1相结合,激发细胞内整合素-β1依赖的FAK磷酸化途径,但LN促进SCs合成ECM的作用并不依赖于整合素-β1介导的信号途径。
Objective To explore the a effects of integrin-β1 during the process of laminin (LN) promoting Schwann cells (SCs) to synthesis extracellular matrix (ECM). Methods SCs were obtained from 10 SD rats and cultured in vitro. After the treatment with ectogenic LN, double fluorescence immunocytochemical staining was performed to observe the expression of LN and integrin-β1 in SCs and the phosphorylation of focal adhesion kinase (FAK) was examined by Western blotting. The SCs surface receptor integrin-β1 was blocked by using Ha2/5 antibody and after the treatment with ectogenic LN, Western blotting was performed to observe the phosphorylation of FAK in SCs and the expression of components of ECM including LN, nidogen and type IV collagen were observed by fluorescence immunocytochemical staining. Results After the treatment with ectogenic LN, SCs had positive coexpression of LN and integrin-β1 and the phosphorylation of FAK was increased. After blocking the SCs surface receptor integrin-β1, phosphorylation of FAK was descended, but the positive expression of LN, nidogen and type IV collagen was not decreased. Conclusion LN can combine with SCs surface receptor integrin-β1 and induce the integrin-β1-depcndent phosphorylation of FAK. But the function of LN promoting SCs to synthesis ECM is independent of integrin-β1 mediated signal pathway.