【摘要】 目的:探讨溶血磷脂酸（LPA）在体外对整合素β₆（ITGB6）表达的影响,并进一步研究LPA诱导的活化转化生长因子β（TGF-β）在此过程中的作用。方法:原代培养的正常人支气管上皮（NHBE）细胞接种于6孔板中,经LPA诱导,收集细胞,分别利用RT-PCR和流式细胞术检测ITGB6 mRNA及细胞表面蛋白的表达;利用转染有TGF-β应答性纤溶酶原激活物抑制剂1（PAI-1）启动子片段并融合萤火虫荧光报告基因片段的转化貂肺上皮细胞（TMLC）作为TGF-β活性报告细胞检测活化的TGF-β。结果:（1）10μmol/L LPA诱导2 h后,ITGB6mRNA在上皮细胞中表达显著增加,具有明显的时间依赖性。（2）10μmmol/L LPA诱导4 h后,上皮细胞表面ITGB6蛋白表达明显增加。（3）抗α_vβ₆抗体可阻断LPA诱导的活化TGF-β,但不能阻断LPA诱导的ITGB6 mRNA的表达。结论:（1）LPA可诱导上皮细胞ITGB6 mRNA和细胞表面蛋白的表达。（2）LPA诱导的ITGB6 mRNA表达不依赖LPA诱导的TGF-β活化。更多还原

【Abstract】 AIM:To investigate the effect of lysophosphatidic acid（LPA） on the expression of integrin B₆（ITGB6） for determining the role of transforming growth factor B（TGF-B） activation induced by LPA in this process. METHODS:Normal human bronchial epithelial（NHBE） cells were primarily cultured in 6 well plate and stimulated with LPA.The mRNA expression of ITGB6 and the level of cell surface ITGB6 protein were detected by RT-PCR and flow cytometry, respectively.The activity of active TGF -βinduced by LPA was measured by the method of transformed mink lung epithelial cells（TMLC） transfected with TGF -βresponsive plasminogen activator inhibitor 1（PAI-1 ） promoter fused with firefly luciferase reporter gene.RESULTS:After stimulated with LPA at concentration of 10μmol/L for 2 h,the mRNA expression of ITGB6 in epithelial cells was significantly increased in a time-dependent manner.The results of flow cytometry showed that the protein level of ITGB6 on cell surface was obviously increased after treated with LPA at concentration of 10μmol/L for 4 h.The active TGF -βinduced by LPA in epithelial cells was blocked by anα_vB₆ blocking antibody. However,α_vP₆ blocking antibody failed to inhibit the mRNA expression of ITGB6 induced by LPA.CONCLUSION: LPA induces the mRNA and cell surface protein of ITGB6 in epithelial cells.The up-regulated ITGB6 expression by LPA is independent on LPA-induced TGF -βactivation.更多还原