TRANSPLANT TOLERANCE IN SWINE--A GENE TRANSFER APPROACH

之前在小型猪身上的研究已经证明，产品 主要组织相容性复合体(MHC)的II类区域 对决定人类命运具有压倒性的重要性 带血管的同种异体移植，很可能在 人类。此外，它最近还在一个 小鼠去髓重建动物模型的建立 转导同种异体MHC基因的同基因骨髓细胞 导致皮片移植物存活时间明显延长 同样的同种异体抗原。在初步学习中，班级的转移 MHC内骨髓移植II基因的研究 重组供者，导致对后续肾脏的长期耐受 II类同种异体移植与骨髓供者匹配，但完全匹配 与收件人不匹配。综上所述，这些结果表明 编码II类抗原的基因的转移可以提供一种 诱导特异性移植耐受的新途径 跨越了完全的组织相容性障碍。的总目标是 该项目是将同种异体II类基因引入到 逆转录病毒介导的小型猪自体骨髓细胞 转导，并确定这一过程的影响 移植免疫指标。对应的cDNA克隆 来自两个SLA单倍型的所有表达的II类基因 以前在这个实验室被分离和测序。这个 本方案的具体目的是：1)构建重组 转录下含SLA-II类cDNA的逆转录病毒 对构成启动子的控制；2)创造条件 同种异体II类基因导入骨髓干细胞的研究 细胞通过这些重组逆转录病毒载体；3)重组 带自体骨髓细胞的去髓小型猪 用同种异体II类cDNA转导，并检测 导入基因的表达；以及4)确定 基因转移诱导移植耐受的实验研究 如体外和体内试验所检测的。这些研究可能 对基因转移技术的使用具有重要的意义 在对同种异体和异体免疫反应的操纵中 异种移植在未来。

Previous studies in miniature swine have demonstrated that products of the class II region of the major histocompatibility complex (MHC) are of overwhelming importance in determining the fate of vascularized allografts, and it is likely that the same is true in human beings. In addition, it has recently been demonstrated in a mouse model that reconstitution of myeloablated animals with syngeneic bone marrow cells, transduced with an allogeneic MHC gene leads to specific prolongation of survival of skin grafts bearing the same alloantigen. In preliminary studies, the transfer of class II genes by bone marrow transplantation from an intra-MHC recombinant donor, led to long-term tolerance to a subsequent renal allograft class II matched to the bone marrow donor but completely mismatched to the recipient. Taken together, these results suggest that transfer of genes encoding class II antigens could provide a new approach to the induction of specific transplantation tolerance across complete histocompatibility barriers. The overall goal of this project is to introduce allogeneic class II genes into autologous bone marrow cells of miniature swine via retroviral transduction and to determine the effects of this procedure on parameters of transplantation immunity. cDNA clones corresponding to all expressed class II genes from two SLA haplotypes have previously been isolated and sequenced in this laboratory. The specific aims of this proposal are to: 1) Construct recombinant retroviruses containing SLA class II cDNAs under the transcriptional control of constitutive promoters; 2) Establish conditions for introduction of allogeneic class II genes into bone marrow stem cells via these recombinant retroviral vectors; 3) Reconstitute myeloablated miniature swine with autologous bone marrow cells transduced with allogeneic class II cDNAs, and examine the expression of the introduced genes; and 4) Determine the effects of class II gene transfer on the induction of transplantation tolerance as detected by in vitro and in vivo assays. These studies could have important implications for the use of gene transfer technology in the manipulation of immune responses to both allogeneic and xenogeneic transplants in the future.