ECDI偶联的人抗原提呈细胞诱导供者抗原特异性CD8^+T细胞耐受的实验研究

Study of ECDI-coupled human antigen presenting cells induce donor-specific CD8^+ T cells tolerance

目的:研究体外模拟异基因移植环境下,碳二亚胺(ECDI)偶联的供者抗原提呈细胞(ECDI-APCs)诱导受者T细胞针对供者抗原特异性耐受的效果。方法:每组以HLA-A、-B、-DR完全错配的3名志愿者外周血淋巴细胞建立混合淋巴细胞培养体系,模拟异基因移植环境。在-6 d将受者外周血单个核细胞(PBMCs)与供者ECDI-APCs共培养,第0天再次加入新鲜分离的原供者APCs或无关供者APCs模拟移植,第8天以流式细胞术检测受者T细胞的增殖情况。结果:ECDI偶联浓度为150 mg/ml,供、受者细胞共培养比例为0.1∶1时,ECDI-APCs可诱导出受者T细胞对原供者抗原刺激的耐受状态(P<0.05),其中受者CD8+T细胞的耐受具有供者抗原特异性(P<0.05),而CD4+T细胞的耐受无抗原特异性(P>0.05)。结论:ECDI-APCs能诱导CD8+T细胞对同种异体抗原刺激的耐受状态,并且具有供者抗原特异性,可为临床器官移植术后供者抗原特异性耐受的建立提供实验依据。

Objective：To investigate the effect of ECDI-coupled donor antigen presenting cells（ECDI-APCs）to induce human donor-specific tolerance for T cells from responder in mimic transplant circumstances in vitro. Methods：For each group,mixed lymphocyte reaction（ MLR） system of PBMCs and ECDI-APCs from three health volunteers,whose HLA-A,-B and-DR fully mismatched,were set up to mimic transplant circumstances in vitro. On day-6,PBMCs from responder and ECDI-APCs from donor were cocultured in MLR system. On day 0,freshly isolated APCs from priming donor or indifferent donor were added as stimulating cells in MLR system. On day 8,proliferation of responder T cells was detected by flow cytometry. Results：ECDI-APCs treatment could induce responder T cells tolerance when APCs was treated with ECDI at a concentration of 150 mg/ml,and ECDI-APCs versus PBMCs at a ratio of 0. 1 ∶1（ P〈0. 05）. Tolerance of CD8~＋T cells rather than CD4~＋T cells had donor specificity. Conclusion：ECDI-coupled donor APCs treatment could induce a potent,antigen-specific tolerance of responder CD8＋T cells,which might hold promises for induction of clinical transplant tolerance in the future.