Induction of transplantation tolerance by co-transplantation of vascularized thymic lobe in miniature swine

为诱导器官移植耐受，本研究对小型猪SLA抗原进行了分析，并对SLA抗原完全不匹配的小型猪器官移植和短期免疫抑制的带血管胸腺叶共移植进行了研究。利用RT-PCR技术对近交系克劳恩小型猪的SLA Ⅰ类和Ⅱ类基因进行了单倍型分析。为了检测小型猪SLA抗原，本研究建立了一种检测SLA Ⅰ类（SLA-1、-2、-3基因）和SLA Ⅱ类（DRB 1基因）的聚合酶链反应-序列特异性引物（PCR-SSP）方法和检测SLA Ⅱ类（DQB 1基因）的聚合酶链反应-限制性片段长度多态性（PCR-RFLP）方法。通过对SLA Ⅰ类和Ⅱ类基因的等位基因分析，鉴定出11种不同的表型和2种新的单倍型。本研究建立了纯种克氏小型猪，鉴定出SLA基因纯合子22头，杂合子19头。我们有 ...更多信息 将17个心脏异位移植到轻度不匹配或MHC-II类不匹配的MHC近交系小型猪中，以评估（1）短期FK 560是否诱导耐受并防止心脏同种异体移植血管病变（CAV）的发展，以及（2）新的免疫抑制剂FK 778是否对细胞和体液免疫应答具有抑制作用。FK 506的12天疗程未能在该模型中诱导耐受，但与对照模型相比，它确实延长了穿过MHC II类错配屏障的平均移植物存活。FK 778和FK 506联合应用可进一步延长移植物的平均存活时间，诱导供体特异性低反应，并抑制CAV的发展。我们以前曾报道过，在切除胸腺的小型猪中，血管化胸腺叶同种异体移植物诱导完全MHC错配的移植耐受的能力。在这项研究中，我们已经调查了长期接受受体猪共同移植后，在完全MHC不匹配的心脏移植异位VLT的机制。所有接受他克莫司治疗的受者维持移植物的时间明显长于仅接受心脏移植的受者，而那些接受他克莫司治疗28天的受者则维持了长期的心脏移植。细胞毒性T-淋巴细胞反应对第三方抗原的细胞从耐受动物显示限制由自身和供体的MHC，而控制的反应仅限于自身的MHC。供体树突状细胞在移植物中的存在和共培养试验的结果表明，中枢和调节机制都参与了实现长期接受。少

To induction of tolerance for organ transplantation, we have performed on analysis of SLA antigens in miniature swine, full SLA antigens mismatched organ transplantation and co-transplantation of vascularized thymic lobe administrated short-term immunosuppression in miniature swine. In inbred Clawn miniature swine, three haplotypes have been assined by RT-PCR of SLA class I and II genes. To determine of SLA antigens of Clawn miniature swine, we have developed a polymerase chain reaction-sequence specific primer (PCR-SSP) method for SLA class I (SLA-1,-2,-3 genes) and SLA class II (DRB1 gene), and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method for SLA class II (DQB1 gene). Based on allele analysis of SLA class I and II genes, eleven different phenotype pattern and two new haplotypes were identified of this study. We have established pure-bred Clawn miniature swine, twenty-two of identified SLA gene homozygotes and nineteen of heterozygotes. We have … More transplanted seventeen hearts heterotopically across either minor mismatched or MHC-class II mismatched MHC-inbred miniature swine to assess (1)whether a short course of FK560 induces tolerance and prevents the development of cardiac allograft vasculopathy (CAV), and (2)whether a new immunosuppressant, FK778,which has been shown to have inhibitory effects on the cellular and humoral immune responses. The 12-day course of FK506 failed to induce tolerance in this model, but it did prolong the mean graft survival across a MHC-class II mismatched barrier compared with control model. The co-administration of FK778 with FK506 further prolong the mean graft survival, induced donor specific hyporesponsineness in vitro, and inhibited the development of CAV. We have previously reported the ability of vascularized thymic lobe (VTL) allografts to induce transplantation tolerance across full MHC mismatch in thymectomized miniature swine. In this study, we have investigated the mechanism of long-term acceptance in recipient swine following cotransplantation of VLT in fully MHC-mismatched cardiac transplantation heterotopically. All recipients that received a VTL maintained their grafts significantly longer than only heart graft, and those receiving 28days of tacrolimus maintained their heart graft long-term. Cytotoxic T-lymphocyte responses against third-party antigens by cells from tolerant animals showed restriction by both self and donor MHC, whereas responses of controls were restricted to self MHC only. The presence of donor dendritic cells in VTL grafts and results of co-culture assays suggested both central and regulatory mechanisms were involved an achieving long-term acceptance. Less