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

为了诱导对器官移植的耐受，我们对小型猪进行了SLA抗原分析、全SLA抗原错配器官移植和带血管胸腺瓣联合移植给予短期免疫抑制。在近交系爪微型猪中，通过RT-PCR鉴定出了SLAⅰ类和ⅱ类基因的3个单倍型。为了测定小型螯猪SLA抗原，我们建立了针对SLAⅰ类（SLA-1、-2、-3基因）和SLAⅱ类（DRB1基因）的聚合酶链反应-序列特异性引物（PCR-SSP）法和针对SLAⅱ类（DQB1基因）的聚合酶链反应-限制性片段长度多态性（PCR-RFLP）法。通过对SLA I类和II类基因的等位基因分析，鉴定出11种不同的表型模式和2种新的单倍型。我们建立了纯种克劳微型猪，鉴定出22个SLA基因纯合子和19个杂合子。我们已经…More移植了17个异位心脏，在轻微错配或mhc - II类错配的mhc近交系微型猪中进行移植，以评估(1)短期FK560是否诱导耐受性并防止心脏异体移植血管病变（CAV）的发展，以及(2)新的免疫抑制剂FK778是否已被证明对细胞和体液免疫反应具有抑制作用。在该模型中，FK506的12天疗程未能诱导耐受，但与对照模型相比，它确实延长了跨越mhc - II类错配屏障的移植物平均存活时间。FK778与FK506共给药可进一步延长移植物平均存活时间，诱导供体特异性低反应，并抑制CAV的发展。我们以前报道过血管化胸腺叶（VTL）异体移植物在胸腺去组织的小型猪中诱导完全MHC错配的移植耐受的能力。在这项研究中，我们研究了在完全mhc错配的异位心脏移植中，VLT在受体猪体内长期接受的机制。所有接受VTL移植的受者比只接受心脏移植的受者维持移植物的时间明显更长，接受28天他克莫司的受者心脏移植的维持时间较长。耐受动物细胞对第三方抗原的细胞毒性t淋巴细胞反应受到自身和供体MHC的限制，而对照组的反应仅受自身MHC的限制。供体树突状细胞在VTL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