ADSCs与HUVECs体外共培养促进HUVECs增殖及成血管化作用

ADSCs promotes the proliferation and vascularization of HUVECs when co-cultured in vitro

目的为制备血管化胰岛,分离、培养脂肪来源干细胞(adipose derived stem cells,ADSCs),观察细胞共培养条件下,ADSCs对人脐静脉内皮细胞(human umbilical vein endothelial cell,HUVECs)增殖及成血管化功能的促进作用并探讨其机制。方法采用胶原酶消化法分别原代培养获得ADSCs与HUVECs,细胞形态学、免疫荧光或多向诱导分化鉴定,建立HUVECs与ADSCs接触式及间接共培养体系,设立HUVECs单独培养为对照组,比较两组成血管化功能、HUVECs增殖状况及上清液血管内皮生长因子(vascular endothelial growth factor,VEGF)、碱性成纤维生长因子(basic fibroblast growth factor,b-FGF)浓度。结果通过原代培养成功获得ADSCs与HUVECs;第3代ADSCs呈均一的长梭形纤维细胞样形态,免疫荧光检测见CD44/CD49d(+)、CD31/CD34(-),并具有多向分化功能;第2代HUVECs免疫荧光检测示vWF/CD31(+)。于Matrigel内接触式共培养4h,ADSCs+HUVECs组血管密度高于HUVECs组;间接共培养时,HUVECs生长曲线于ADSCs+HUVECs组上移,在对数生长期的第3、4、5天,ADSCs+HUVECs组HUVECs计数为(4.52±0.31)×104、(7.18±0.45)×104、(8.23±0.36)×104,大于单独HUVECs组的(2.71±0.25)×104、(4.87±0.26)×104、(6.86±0.33)×104(P<0.01);ADSCs+HUVECs组HUVECs群体倍增时间为(1.36±0.23)d,短于单独HUVECs组的(1.62±0.31)d。四甲基噻唑蓝(methylthiazol tetraztlium,MTT)法测定HUVECs的A值培养第1、3、5、7天的ADSCs+HUVECs组高于单独HUVECs组(P<0.01)。培养第3、7、13天时ADSCs+HUVECs组上清液VEGF、b-FGF浓度均高于HUVECs组(P<0.01)。结论 ADSCs与HUVECs共培养时,ADSCs可能通过分泌或增加HUVECs分泌VEGF、b-FGF等细胞因子,进而促进HUVECs增殖及成血管化。

ABSTRACT：Objective For preparation of vascularized islets , to isolate and culture human adipose derived stem cells , investigate the role of adipose derived stem cells （ADSCs ） in promoting the proliferation and vascularization of human umbilical vein endothelial cells （HUVECs ） co‐cultured in vitro , and explore its mechanism .Methods ADSCs and HUVECs were isolated by collagenase digestion method ,then cultured ,and identified by morphology ,immunofluorescence or multi‐directional differentiation .The co‐culture system of ADSCs and HUVECs was established , HUVECs cultured alone were set up for control group . The proliferation , vascularization and concentration of vascular endothelial growth factor （VEGF） and basic fibroblast growth factor （b‐FGF）in the supernatant were compared between the two groups .Results The third generational ADSCs had uniform long spindle fiberous morphology and multi‐directional differentiational function . Immunofluorescence test of surface antigens on ADSCs revealed CD44/CD49d （＋ ） ,CD31/CD34 （-） ,on HUVECs CD31/vWF （＋ ） . High vascular density was found when co‐cultured in Matrigel of ADSCs and HUVECs than alone of HUVECs .Growth curve shown at days 3 , 4 and 5 of the logarithmic phase , HUVECs count in co‐culture group of ADSCs and HUVECs was （4 .52 ± 0 .31） × 10^4 ,（7 .18 ± 0 .45） × 10^4 ,and （8 .23 ± 0 .36） × 10^4 under indirect co‐culture condition , while that in individual HUVECs group was （2 .71 ± 0 .25） × 10^4 ,（4 .87 ± 0 .26） × 10^4 ,and （6 .86 ± 0 .33） × 10^4 （ P〈0 .01） .Population doubling time of HUVECs was shorter in co‐culture group than in individual group .Also ,the OD value of HUVECs was higher in co‐culture group than in individual group when cultured at days 1 ,3 ,5 and 7 （ P〈0 .01） .When cultured at days 3 ,7 and 13 ,the concentration of VEGF and b‐FGF in the supernatant was higher in co‐culture group than in individual group （ P〈 0 .01 ） . Conclusion ADSCs can promote the proliferation and vascularization of HUVECs in vitro co‐culture conditions by secreting or increasing the HUVECs secretion of VEGF and b‐FGF .