体外转染可溶性IL-1RI-Ig基因延长糖尿病小鼠移植胰岛细胞存活时间

目的 探讨糖尿病小鼠移植经可溶性白细胞介素1(IL-1)受体胞外段Fc融合蛋白(sIL-1RI-Ig)基因修饰的胰岛细胞对延长移植物存活时间的作用及机制.方法 将Ad-sIL-1RI-Ig体外转染Balb/c小鼠的胰岛细胞,并将其移植给糖尿病C57BL/6小鼠,观察移植物的存活时间,并检测移植局部组织炎症细胞的浸润以及炎症细胞因子的表达.结果 糖尿病小鼠移植转染sIL-1RI-Ig基因的胰岛细胞后,血糖水平很快下降至正常范围,胰岛移植物存活时间达(39±3)d,而移植正常胰岛细胞的小鼠胰岛移植物存活时间为(9±2)d(P<0.01).糖尿病小鼠移植转染sIL-1RI-Ig基因的胰岛细胞后,胰岛素分泌量随糖负荷增加而升高,并与胰岛素分泌功能正常的小鼠呈相似变化趋势(P>0.05).糖尿病小鼠移植转染sIL-1RI-Ig基因的胰岛细胞后,移植局部组织表达肿瘤坏死因子α(TNF-α)、γ干扰素(IFN-γ)和RANTES等水平明显下调;病理学观察发现移植局部组织浸润的炎症细胞明显少于移植正常胰岛细胞的小鼠.结论 sIL-1RI-Ig基因转染胰岛细胞后,可通过表达sIL-1RI-Ig,阻断IL-1的作用,降低TNF-α、IFN-γ、RANTES等细胞因子的表达,从而减轻排斥反应,延长胰岛细胞移植物的存活时间和提高胰岛素分泌功能.

Allograft survival in diabetic mice transplanted with Sil-1RI gene-modified islet cells

Objective To discuss the effect of sIL-1RI on allograft survival after islet transplantation.Methods Islets were isolated and transfected with Ad-sIL-1RI-Ig.Mice were treated with STZ to induce insulin-dependent diabetes mellitus(IDDM) model.Islet transplantation was carried out to IDDM mice with sIL-1RI-Ig gene-modified islet cells.Then the survival time of grafts was tested by daily observing blood glucose and insulin levels.The expression of cytokines was detected in graft after transplantation by using RT-PCR. Pathological changes of the graft were also observed by chromoscopy with HE after transplantation.Results The survival time of the grafts in sIL-1RI-Ig-islet group (39±3 days) was prolonged significantly (P<0.01) as compared with controls.A down-regulation of cytokines expression was detected in grafts after transplantation.Less damage and infiltration of lymphocytes were found in sIL-1RI-Ig gene-transfected group.Conclusion The effects of islet cells modified with sIL-1RI-Ig before transplantation on the rejection of murine islet allograft were investigated.The results verified that sIL-1RI-Ig-modified islet allograft could prolong the survival of grafts significantly,and demonstrated it was possible that sIL-1RI-Ig preventedallograft rejection via reducing the expression of cytokines(TNF-α,IFN-γ,RANTES,etc.).