骨髓间充质干细胞向血管内皮细胞分化过程在银屑病发病中的作用

目的:将银屑病患者骨髓间充质干细胞(BMMSCs)体外分化为血管内皮细胞(VEC),并对定向分化的VEC活性进行初步研究,为银屑病患者BMMSCs生物特性的深入研究提供依据。方法:寻常型银屑病患者20例,健康对照组15例为骨髓象正常者。采用密度梯度离心法分离骨髓单个核细胞,通过贴壁法培养BMMSCs,流式细胞仪鉴定细胞表面标志;加入血管内皮细胞生长因子(VEGF)、碱性成纤维细胞生长因子(bFGF)定向诱导BMMSCs向VEC分化,流式细胞仪进行细胞表型鉴定;免疫细胞荧光技术鉴定VEC标志物VWF的表达;体外血管成形试验检测诱导的内皮细胞体外成形能力。结果:流式测定显示两组培养的BMMSCs高表达CD44、CD29,而HLA-DR、CD45、CD34阴性表达;银屑病组CD34、CD45、ICAM-1、HLA-DR阳性表达,且明显高于对照组(P﹤0.05);免疫细胞化学显示两组都可分化为VEC,与正常对照组比较具有统计学差异(P﹤0.05),银屑病患者诱导的VEC体外血管成形能力较强。结论:银屑病患者BMMSCs生物学活性异常,且易于转分化为VEC。银屑病患者BMMSCs-VEC发育分化系统在银屑病患者皮损真皮乳头层微血管异常增生过程中可能发挥重要的作用。

Preliminary study on the differentiation of bone marrow mesenchymal stem cells in psoriatic patients to vascular endothelial cells in vitro

Objective:The activity of psoriatic blood vessel endothelial cells(VEC),oriented differentiated from patients bone marrow mesenchymal stem cells(BMMSCs) in vitro,was detected in order to providing some basis for the further researches of BMMSCs biological characteristics in patients with psoriasis.Methods:This study recruited 15 healthy controls with normal bone marrow picture and 20 patients with psoriatic vulgaris.BMMSCs of patients with psoriasis and control were gained after density gradient isolation combined with adherence isolation.The phenotypes of the cells were identified by flow cytometry.To oriented differentiate the BMMSCs into VEC,VEGF and bFGF was added into endothelial cell growth medium.The induced BMMSCs were detected by flow cytometry to find whether they had endothelial cell phenotypes.The expression of endothelial-specific markers VWF was assayed by immunofluorescence cytochemistry.The characteristic capillary-like structures forming ability of differentiated cells was tested using in vitro angiogenesis test kit.Results:Flow cytometry results showed that surface antigens CD44 and CD29 were highly expressed while CD34,CD45,HLA-DR were negatively expressed in the BMMSCs.The expressions of CD34,HLA-DR,CD54 and CD45 were weak positive in both test group and control.And the expression level of test group was significantly higher than control(P<0.05).Immunocytochemistry results showed that both the two groups can differentiate into vascular endothelial cells,and the expression level of test group was significantly higher than control(P<0.05).The capillaries forming ability in semisolid medium in patients was higher than in control.Conclusion:The psoriatic BMMSCs biological characteristics were abnormal and they were prone to differentiate into VEC.Psoriasis BMMSCs-VEC system play important roles in the attack of the abnormal growth of microvascular proliferation of papillary layer in lesional dermis in patients.