目的研究CD151-整合素复合体在CD151促进人脐静脉内皮细胞(HUVECs)迁移中的作用及机制。方法包装携带CD151、CD151-整合素结合突变体(CD151-AAA)和GFP的重组腺相关病毒,转染HUVECs。利用改良的Boyden趋化小室检测细胞迁移能力;Western blot检测各转染组细胞中CD151、磷脂酰肌醇(-3)激酶(PI3K)蛋白的表达;免疫共沉淀法检测各组细胞CD151和整合素α3的结合能力。结果 (1)CD151组较Control组及GFP组显著促进细胞的迁移,而CD151-AAA组细胞的迁移能力较CD151组明显下降,差异具有统计学意义(P〈0.05)。(2)CD151高表达促进PI3K信号通路激活,而CD151-AAA组PI3K信号通路的激活被减弱。(3)免疫共沉淀结果显示CD151与整合素α3结合形成复合体,但CD151-AAA突变破坏了CD151和整合素α3的结合。结论 CD151促进细胞迁移依赖于与整合素结合形成复合体,而破坏该复合体形成则导致CD151促细胞迁移能力显著减弱;该作用与PI3K信号通路的激活有关。
Objective To examine the role of CD151-integrin complex in CD151-promoted migration of human umbilical vein endothelial cells(HUVECs)and the possible mechanisms.Methods rAAV-CD151,rAAV-CD151-AAA and rAAV-GFP were constructed and transfected into HUVECs.The migration of HUVECs was detected by using modified Boyden chamber assay;the expression of CD151 and PI3Kwas detected by Western blotting.The immunoprecipitation was used to determine the conjugation between CD151 and integrinα3.Results(1)Cell migration was significantly promoted in CD151 group when compared with Control and GFP groups,but it was significantly declined in CD151-AAA group when compared with CD151group(P0.05).(2)Overexpression of CD151 could activate the PI3 Ksignaling pathway,which was suppressed in the CD151-AAA group.(3)The immunoprecipitation results showed the formation of CD151-integrin complex in CD151 group.However,CD151-AAA mutation destroyed the conjugation between CD151 and integrinα3.Conclusion The ability of CD151-induced HUVECs migration depends on the formation of CD151-integrin complex.Impairment of the complex leads to the decline in the CD151-induced migrating ability.The activation of PI3 Ksignaling pathway is involved in this process.