目的观察肿瘤转移抑制基因KAI1/CD82在自然流产绒毛和蜕膜组织中的表达情况,并建立蜕膜基质细胞(decidual stromal cell,DSC)与滋养细胞共培养模型,探讨KAI1/CD82在人母-胎界面的生物学作用。方法分别采用RT-PCR和Real-time PCR、免疫组化和Western blot技术分析KAI1/CD82在人早孕期正常妊娠和自然流产的绒毛和蜕膜组织中的转录及翻译水平。模拟体内微环境,建立了DSC和滋养细胞BeWo细胞株共培养体系,利用RNA干扰沉默DSC细胞KAI1/CD82表达,探讨DSC是否通过表达KAI1/CD82对滋养细胞侵袭性发挥调节作用。结果自然流产母-胎界面KAI1/CD82转录水平明显高于正常妊娠(P〈0.05);自然流产的蜕膜组织KAI1/CD82蛋白表达也明显高于正常妊娠(P〈0.05);而绒毛组织及滋养细胞不表达KAI1/CD82蛋白。采用RNA干扰技术成功沉默DSC细胞KAI1/CD82表达;KAI1/CD82基因沉默后,与DSC细胞共培养的BeWo细胞侵袭力显著增强。结论 DSC通过表达KAI1/CD82控制滋养细胞的侵袭,而一旦DSC异常过表达KAI1/CD82将导致滋养细胞侵袭力异常降低,最终可能导致自然流产的发生。
Objective To evaluate the expression of the metastasis-suppressor gene KAI1/CD82 in human decidua and villus,and to explore the regulation of KAI1/CD82 in the cross-talk between decidual stromal cells(DSCs) and trophoblasts.Methods RT-PCR and Real-time PCR were used to investigate the transcription of KAI1/CD82,Western blot and immunohistochemistry were applied to explore the translation of KAI1/CD82 in the decidua and villus from pregnancy wastage with the normal early pregnancy as control.The co-culture system including DSCs and BeWo cell lines was established to investigate the regulation of DSCs on the invasiveness of trophoblast cells.RNAi was used to knock down KAI1/CD82 in DSCs to investigate effects of DSC-expressed KAI1/CD82 on the invasiveness of trophoblast cells.Results The mRNA level of KAI1/CD82 in the villi and the decidua of the pregnancy wastage was significantly higher than that of the normal early pregnancy,and the protein level of KAI1/CD82 in the decidua of the pregnancy wastage was also significantly higher than that of the normal early pregnancy.The protein translation of KAI1/CD82 was not found in the villi.The silencing of KAI1/CD82 was constructed in DSCs.The invasiveness of BeWo cell lines was increased significantly after KAI1/CD82 in DSCs was silenced in the co-culture system.Conclusions KAI1/CD82 expressed in the decidual stromal cells can control the invasion of trophoblast cells,and the abnormal high expression of KAI1/CD82 in DSCs will weak the invasion of trophoblast cells and lead to the early pregnancy wastage.