人脐带Wharton胶间质干细胞的免疫特性研究

目的 对人脐带Wharton胶间质干细胞(human umbilical cord Wharton's Jelly-derived MSC,hWJMSC)进行免疫特性的体外和体内研究,探讨其应用于临床的可行性.方法 取人脐带并分离Wharton胶,组织块法培养hWJMSC,通过细胞表面干细胞标志和多向分化实验对其进行鉴定;通过流式细胞术、免疫组织化学及RT-PCR等实验方法体外检测hWJMSC的主要组织相容性抗原(HLA-ABC和HLA-DPDQDR,即MHC-Ⅰ和MHC-Ⅱ)、表面共刺激分子(CD40、CD80、CD86)和免疫抑制分子(HLAC、IDO、PGE2)等的表达;通过细胞因子蛋白芯片和Western blot实验检测并验证hWJMSC中与免疫抑制相关的细胞因子(IL-10、TGF-β、VEGF、HGF)的表达;另外,还构建了hWJMSC-支架复合体,将其埋人家兔背部皮下,观察其在体内的免疫反应.结果 从人脐带Wharton胶中分离、培养获得长梭形细胞,经流式细胞术及多向分化实验鉴定其为间质干细胞;流式细胞术及免疫组化等检测显示所分离的hWJMSC不表达MHC-Ⅱ,表达MHC-Ⅰ,阳性表达免疫抑制因子HLA-G、IDO、PGE2以及免疫抑制相关细胞因子IL-10、TGF-β、VEGF、HGF,表明其具有低免疫原性和诱导免疫耐受的能力;hWJMSC-支架埋人家兔皮下未引起免疫反应.结论 hWJMSC的免疫原性低,具有抑制免疫排斥、诱导宿主免疫耐受的能力,可应用于异体移植.

Abstract：

Objective To probe the immunological traits of mesenchymal stem cells derived from umbilical cord Wharton's jelly (WJMSCs). Methods The diced Wharton's jelly which was from healthy fullterm birth human umbilical cord was cultured. The mesenchymal stem cells were identified with mesenchymal stem cells markers expression by flow cytometry and multiple differentiation ability. The expression of MHC- Ⅰ / Ⅱ, costimulatory molecules (CD40, CD80 and CD86) was detected with flow cytomctry, immunocytochemistry, and RT-PCR. The expression of immune inhibitors like HLA-G, IDO, and PGE2 was detected by immunocytochemistry and RT-PCR. The expression of immune-related molecules as IL-10, TGF-β, FGF and VEGF was detected with antibody microarray and western blot. Further more, to clarify the in vivo immune reaction of hWJMSCs, we fabricated the hWJMSC-scaffold constructs and implanted them into the rabbit backs. The lymphocyte infiltration and implanted cell survival observed with immunofluorescence. Results After culturinge of diced Wharton's jelly tissue, we obtained spindle-shaped cells. With differentiation medium, the cells can differentiate into osteoblasts, chongdrocytes, adipose cells and schwann cells. Expression of MHC, costimulatory molecules, and a series of immune suppressive-related molecules was found. Immune inhibitors as HLA-G, 1DO, PGE2, and immune suppressive related molecules as HGF, VEGF, TGFand IL-10 were positively expressed. But the cells did not express MHC-Ⅱ. No immune rejection was observed in vivo after implantation of hWJMSC-scaffold constructs. Conclusion It can be concluded that hWJMSCs have very low immunogenicity, which means the cells have potential to induce immune tolerance.The hWJMSCs do not provoke immune rejection in vivo.

Immunological traits of mesenchymal stem cell derived from Umbilical cord Wharton's jelly

Objective To probe the immunological traits of mesenchymal stem cells derived from umbilical cord Wharton's jelly (WJMSCs). Methods The diced Wharton's jelly which was from healthy fullterm birth human umbilical cord was cultured. The mesenchymal stem cells were identified with mesenchymal stem cells markers expression by flow cytometry and multiple differentiation ability. The expression of MHC- Ⅰ / Ⅱ, costimulatory molecules (CD40, CD80 and CD86) was detected with flow cytomctry, immunocytochemistry, and RT-PCR. The expression of immune inhibitors like HLA-G, IDO, and PGE2 was detected by immunocytochemistry and RT-PCR. The expression of immune-related molecules as IL-10, TGF-β, FGF and VEGF was detected with antibody microarray and western blot. Further more, to clarify the in vivo immune reaction of hWJMSCs, we fabricated the hWJMSC-scaffold constructs and implanted them into the rabbit backs. The lymphocyte infiltration and implanted cell survival observed with immunofluorescence. Results After culturinge of diced Wharton's jelly tissue, we obtained spindle-shaped cells. With differentiation medium, the cells can differentiate into osteoblasts, chongdrocytes, adipose cells and schwann cells. Expression of MHC, costimulatory molecules, and a series of immune suppressive-related molecules was found. Immune inhibitors as HLA-G, 1DO, PGE2, and immune suppressive related molecules as HGF, VEGF, TGFand IL-10 were positively expressed. But the cells did not express MHC-Ⅱ. No immune rejection was observed in vivo after implantation of hWJMSC-scaffold constructs. Conclusion It can be concluded that hWJMSCs have very low immunogenicity, which means the cells have potential to induce immune tolerance.The hWJMSCs do not provoke immune rejection in vivo.