β3整合素在生长因子促血管平滑肌细胞粘附和迁移中的作用

Effects of β_3 integrin on adhesion and migration of vascular smooth muscle cells induced by growth factor

目的:探讨血小板衍生生长因子(PDGF)对β3整合素表达的影响及β3整合素在PDGF促血管平滑肌细胞(VSMC)粘附、迁移和增殖中的作用.方法:用抗β3整合素胞外域抗体封闭VSMC β3整合素后,通过[3H]-TdR掺入、细胞粘附、细胞迁移分析及RT-PCR等方法,检测PDGF对β3整合素表达及对VSMC粘附、迁移和增殖的影响.结果:阻断β3整合素与细胞外基质(ECM)蛋白相互作用后,可在一定程度上抑制PDGF刺激的VSMC增殖,使[3H]-TdR掺入率降低39%;在β3整合素抗体浓度为10 mg/L时,PDGF引发的细胞粘附和迁移受到显著抑制(P＜0.05);PDGF作用于VSMC 6 h,β3整合素基因表达活性达到峰值,比对照细胞高87%.结论:PDGF可显著诱导β3整合素在VSMC中表达;β3整合素与ECM蛋白相互作用在PDGF促VSMC粘附、迁移方面发挥重要作用.

AIM: To investigate the effect of platelet-derived growth factor (PDGF) on β_3 integrin gene expression and the role of β_3 integrin on adhesion, migration and proliferation of vascular smooth muscle cells (VSMC) induced by PDGF. METHODS: β_3 integrin gene expression was detected by RT-PCR. After β_3 integrin extracellular domain was blocked, VSMC adhesion, migration and proliferation were measured by adhesion assay, a wound-culture model and [~3H]-TdR incorporation, respectively. RESULTS: After the interaction between β_3 integrin and extracellular matrix was blocked, VSMC proliferation was inhibited in some degree and the rate of [~3H]-TdR incorporation into VSMC decreased 39%. The cell adhesion and migration were significantly inhibited when 10 mg/L anti-β_3 integrin antibody was added (P<0.05). When VSMC were treated by PDGF for 6 hours, the expression of β_3 integrin gene was 87% higher than that of control. CONCLUSION: PDGF significantly induces expression of β_3 integrin gene in VSMC, and the interaction between β_3 integrin and ECM protein may play an important role in VSMC adhesion and migration.