水溶性一氧化碳释放分子抑制供肾树突状细胞活化减轻移植后排斥反应

Water-soluble CO-releasing molecules inhibit activation of donor renal dendritic cells and suppress graft rejection

目的研究水溶性一氧化碳释放分子3（CORM-3）减轻小鼠肾移植后排斥反应的作用及机制。方法以C57BL／6J小鼠为供鼠，Balb／c小鼠为受鼠，采用随机数字表法将供、受鼠分为2组，制备小鼠肾移植模型。CORM-3组受鼠接受经CORM-3预处理的供肾，iCORM组受鼠接受经无CO活性的iCORM预处理的供肾。术后检测各组受鼠的血清肌酐（SCr）水平，观察各组移植肾组织的病理改变，记录各组移植肾存活时间。以C．FVB-Tg（Itgax-DTR／GFP）57Lan／J小鼠为供鼠，Balb／czb鼠为受鼠，肾移植后24h通过流式细胞仪检测移植肾内供鼠rDC的活化情况。结果术后iCORM组和CORM-3组间移植肾中位存活时间分别为40．5和70d（P〈0．05）；术后两组受鼠的SCr水平均进行性升高，但CORM-3组受鼠的SCr水平始终保持在较低的水平（P〈0．05或P〈0．01）；与正常小鼠肾组织相比，术后第4周iCORM组受鼠的移植肾间质出现弥漫性单个核细胞浸润，中度肾小管炎症，以及部分肾小球硬化；CORM-3组移植肾组织单个核细胞浸润较iCORM组明显减轻，肾小球与肾小管形态基本正常。移植后24h，iCORM组和CORM-3组移植肾内供鼠rDC表面均高表达CDS0和CD86，表明rDC处于活化状态，而CORM-3组rDC表面CD80和CD86的表达较iCORM组明显减少（P〈0．05）。结论CORM-3可显著减轻同种肾移植小鼠的排斥反应，改善移植肾功能，其机制可能是CORM-3抑制了移植后供鼠rDC的活化。

Objective To investigate the effect and underling mechanism of water-soluble CO- releasing molecules （CORM-3） on the alleviation of allograft rejection after mouse kidney transplantation. Methods A mice kidney transplantation model was established using C. FVB-Tg （Itgax-DTR/GFP）57Lan/J or C57BL/6J （H-2Kb） mice as donors, and Balb/c （H-2Kd） mice as recipients. After donor nephrectomy, kidney was preserved in UW solution which contained CORM-3 or iCORM （inactive CO-releasing molecules） for 24 h in 4℃. Recipient survival after removal of both na？ ve kidneys, serum creatinine as well as graft histology was observed. In the C. FVB-Tg （Itgax- DTR/GFP） 57Lan/J donors, rDCs were acquired in vitro and selected by magnetic cell sorting （MACS） after graft nephrectomy. The expression of activation markers, CD80 and CD86, on rDC was assessed by using flow cytometry. Results The graft medium survival time was 40. 5 days in the iCORM group and 70 days in the CORM-3 group respectively （P〈0. 05）. CORM-3 preserved the graft function as shown by significantly lower serum creatinine （P〈0. 05 ; or P〈0. 01 ） and alleviated graft pathology injury. Diffuse infiltration of mononuclear cells in the interstitial tissues, moderate tubulitis and partial glomerular sclerosis were found in the iCORM graft kidney, while the CORM-3 graft kidney displayed almost normal histology. Meanwhile, CORM-3 suppressed the expression of CD80 and CD86 in donor-derived rDC. Conclusion CORM-3 can alleviate allograft rejection, prolong the graft survival, and improve kidney function in mouse kidney transplantation, probably via inhibiting rDC activation.