【摘要】 目的探讨结缔组织诱导人胎儿骨髓间充质干细胞(BMSCs)分化为上皮细胞的机制。方法取20例孕16～20周因故引产胎儿,10例选择性剖宫产妇羊膜,酶联免疫吸附测定(ELISA)法检测去上皮羊膜和胎儿肠壁结缔组织中表皮生长因子(EGF)的含量;分离、培养、扩增胎儿BMSCs;将4,6-二脒基-2-苯基吲哚(DAPI)标记的第3代BMSCs(P3-BMSCs)种植于羊膜上,分别加入肠壁结缔组织上清液、羊膜上清液(均含EGF 30μg/L)、外源性EGF 30ug/L、30ng/L、完全培养基(1～5组)中。培养7d后,免疫组织化学和激光扫描共焦显微镜检测BMSCs表达的细胞角蛋白(CK)及CK20。结果每100mg肠壁结缔组织及羊膜中EGF含量分别为(320.22±0.257)pg、(299.20±0.994)pg。羊膜与肠壁结缔组织上清液或羊膜上清液联合诱导BMSCs后,其CK和CK20阳性细胞率均明显强于羊膜与外源性EGF诱导组以及单纯羊膜诱导组,P<0.01。羊膜与肠壁结缔组织上清液诱导后BMSCs表达CK20高于羊膜与羊膜上清液组,P<0.05。羊膜诱导组与外源性EGF联合诱导组间的差异无统计学意义。结论直接接触可能是羊膜结缔组织诱导BMSCs向上皮细胞分化的机制之一。肠壁结缔组织上清液和羊膜上清液均能联合羊膜诱导BMSCs向上皮细胞及具有肠上皮细胞表型的细胞分化。更多还原

【Abstract】 Objective To observe the mechanism of the bone marrow mesenchymal stem cells(BMSCs) induced by connective tissue differentiate into epithelial cells.Methods Content of epidermal growth factor(EGF) in amnion removed epithelium and foetus intestinal connective tissue were detected by ELISA.BMSCs obtained from fetus aged 16-20 weeks were isolated,cultured and proliferated in vitro.The DAPI marked P3-BMSCs were planted on the amnion,and added supernatant of intestinal connective tissue or amnion supernatant(both contained final concentration of 30ng/ L EGF),and exogenous EGF 30μg/L,30 ng/L,0,group 1-5 respectively.At the cultivated 7th day,the expressions of cytokeratin(CK)、CK20 in BMSCs were observed with immunofluorescence method and CLSM.Results There were(320.22 ± 0.257)pg,(299.20 ± 0.994)pg EGF in the fetal intestinal connective tissue or amnion/ 100mg respectively.After induced by amnion and supernate of intestinal connective tissue or amnion,the CK and CK20 positive cells in BMSCs were obviously stronger than that in groups induced by amnion and exogenous EGF and in group induced only by amnion,P < 0.01.The CK20 positive cells in group induced by amnion and supernate of intestinal connective tissue were much more high than that in group induced by amnion and supernate of amnion,P < 0.05.The difference of CK and CK20 positive cells was not statistically significant among the group induced by amnion and exogenous EGF and in group induced only by amnion.Conclusion The direct contact may be one of mechanism tnat amnion induces BMSCs to differentiate into epithelial cell.Both supernate of intestinal connective tissue and supernate of amnion combined with amnion could induce BMSCs to differentiate into epithelial cell and expressing the phenotype of intestinal epithelial cells.更多还原