反义肽核酸阻断CC趋化因子受体5途径延长同种异体胰岛移植物存活

Blocking the CC chemokine receptor 5 pathway by antisense peptide nucleic acid prolongs islet allograft survival

目的探讨CC趋化因子受体5(CCR5)反义肽核酸对同种异体胰岛移植急性排斥反应的影响。方法建立小鼠胰岛移植模型用于检测以CCR5为靶位的PNA CCR5在体内对急性胰岛移植排斥的效应。通过混合淋巴细胞培养(MLR)来评估体外T细胞增殖应答能力。应用RT-PCR和Western blot检测mRNA和蛋白表达水平。结果与生理盐水对照组[(6.5±0.58)d]和随机PNA错配组[(6.5±0.50)d]相比,PNA CCR5处理组有功能胰岛移植物存活时间明显延长[(12.0±1.75)d](P均<0.01)。移植后第7天,PNA CCR5组的CCR5 mRNA表达水平(0.56±0.05)明显低于对照组和错配组(1.68±0.07和1.80±0.14)(P均<0.01)。PNA CCR5组移植物CCR5蛋白水平亦较对照组和错配组明显下降(P均<0.01)。PNA CCR5组小鼠淋巴细胞增殖能力亦明显降低。结论PNA CCR5能延长同种异体胰岛移植物的存活时间,在抑制同种异体急性排斥反应中具有潜在的治疗效应。

Objective To identify the effect of peptide nucleic acid of CC chemokine receptor 5 on acute rejection of islet allograft. Methods Mice islet transplant models were used to test the effect of PNA CCR5 by targeting CCR5 in acute allograft rejection. In vitro T cell proliferative responses were assessed by mixed lymphocyte response （ MLR ）. RT-PCR and Western blot were used to detect the expression of mRNA and protein. Results PNA CCR5 -treated recipients demonstrated statistically significant prolongation [ （12.00 ± 1. 75 ） d ] in functional allograft survival when compared with saline [ （ 6. 50 ± 0. 58 ） d ] or PNA mismatch-treated recipients [ （ 6. 50 ± 0. 50 ） d ]. The CCR5 mRNA expression level of PNA CCR5, control, and PNA mismatch treatment recipients at day 7 posttransplant was 0.56 ± 0. 05, 1.68 ± 0.07 and 1.80 ± 0. 14, respectively. The data showed that CCR5 protein was significantly down-regulated in PNA CCR5 treatment allografts compared with saline and PNA mismatch treatment allografts （ P 〈 0. 01 , P 〈0.01 ）. Lymphocytes from PNA CCR5 treatment mice also exhibited a reduced degree of proliferation. Conclusions The present study indicates that PNA CCR5 can prolong the survival time of islet allograft, and has a potential therapeutic effect on inhibiting acute allograft rejection.