WYE-354调控小鼠同种异体皮肤移植抗排斥反应中的mTOR信号传导通路

目的探讨mTOR激酶ATP竞争抑制剂WYE-354对小鼠同种异体皮肤移植抗排斥反应的作用及机制。方法以C57BL/6为受者,BALB/c为供者建立同种异体皮肤移植模型,C57BL/6小鼠行同种同体皮肤移植为自体移植组。移植-2d给药,共21d,阳性对照组为同种异体皮肤移植,雷帕霉素组口服给药0.2ml、剂量1mg/(kg.d),WYE-354药物组腹腔注射0.2ml:低剂量1mg/(kg.d)、中剂量1.5mg/(kg.d)、高剂量50mg/(kg.d)。术后3、7、11、21d时,应用免疫印记法留样检测每组脾细胞4E-BP1磷酸化水平,11d行皮肤移植物组织病理染色。结果阳性对照组皮肤移植物存活时间明显少于雷帕霉素组、WYE-354低、中、高剂量组,差异有统计学意义(P<0.01);雷帕霉素组皮肤移植物存活时间明显少于WYE-354中、高剂量组,差异有统计学意义(P<0.01)。雷帕霉素组及WYE-354低剂量组皮肤移植物局部淋巴细胞浸润较阳性对照组减少,WYE-354中、高剂量组皮肤移植物局部淋巴细胞浸润较阳性对照组、雷帕霉素组、WYE-354低剂量组均减少。雷帕霉素组、WYE-354低、中、高剂量组均可下调脾细胞中4E-BP1蛋白的磷酸化水平,以WYE-354中、高剂量组作用最为明显。结论 WYE-354可以抑制mTOR信号转导通路相关蛋白磷酸化水平的调控,并阻滞其细胞周期,减少淋巴细胞向皮肤移植物浸润、显著延长小鼠皮肤移植物存活时间。

WYE-354 regulates signal transduction pathway of mammalian target of rapamycin in anti-rejection of mice after skin allograft

Objective To study the role of WYE-354,an ATP-competitive mammalian target of rapamycin(mTOR) kinase inhibitor,in anti-rejection of mice after skin allograft and its mechanism.Methods A skin allograft model was established with BALB/c mice as the donor and C57BL/6 mice as the recipient.The mice were divided into auto-graft group(control group) and allograft group(WYE-354 group).Mice in control group were given rapamycin and WYE-354 2 days after operation for 2 days and those in WYE-354 group received oral 0.2ml rapamycin(1mg/kg·d) and injection of WYE-354 at dose of 1mg/(kg·d),1.5mg/(kg·d) and 50mg/(kg·d),respectively.On days 3,7,11,and 21 after operation,4E-BP1 phosphorylation levels in spleen cells were measured by Western blot.On day 11 after operation,skin tissue sample was stained with H&E.Results The survival time of mice in WYE-354 group was longer than that of mice in control group(P<0.01).The survival time of mice in control group was longer than that of mice in medium and high dose WYE-354 groups(P<0.01).The number of locally-infiltrated lymphocytes was less in low dose WYE-354 group than in control group.The 4E-BP1 phosphorylation level in spleen cells was down-regulated in control group and low,medium and high WYE-354 groups,especially in high dose WYE-354 group.Conclusion WYE-354 can inhibit the 4E-BP1 phosphorylation level related with the mTOR signal transduction pathway,block the cell cycle,reduce the infiltration of lymphocytes to skin grafts,and prolong the survival time of mice after skin graft.