T cell repertoire of graft-versus-host disease and graft-versus-tumor effects

描述(申请人提供)：在异基因血液和骨髓移植(BMT)后，成熟的供者T细胞可以增强植入，对抗机会性感染，并启动移植物抗肿瘤(GVT)反应，但存在发展为移植物抗宿主病(GVHD)的风险。异基因骨髓移植作为治疗癌症的免疫疗法未来的关键在于能否增强供者T细胞在介导移植物抗宿主病中的有益作用，同时将其引起移植物抗宿主病的能力降至最低。实现这一目标的一种方法是选择性地耗尽造血干细胞接种中的同种异体反应性T细胞亚群。在这一点上，CDR3大小谱型的TCRV？谱系分析可以成为表征同种异体反应性T细胞反应的有力工具。这项建议的总体目标是通过集中在供体抗宿主微小组织相容抗原(MIHA)T细胞是如何发展的，以及TCR在靶组织的疾病发病机制和GVT反应中所涉及的特异性的广泛定义来研究致死性GVHD和GVT效应的免疫生物学。为此，将利用B10.BR-&GT；CBA和C57BL/6(B6)-&GT；CXB-2，B6-&GT；BALB.B，B6-&GT；CXB-3和B6-&GT；CXB-7错配菌株组合移植模型。在这些移植模型中，不同程度的GVHD的发病机制都是由CD8和/或CD4T细胞介导的。此外，还将研究造血室外的宿主元素作为移植物抗宿主病免疫调节剂的作用。参与GVHD和GVT反应的T细胞谱系将通过TCRV？分型进行分析。后一项研究将通过用宿主来源的小鼠髓系白血病细胞(MMC6和MME4)挑战CBA或CXB-2小鼠来完成。这种谱型分析将用于指导供者T细胞接种的操作，以努力减少GVHD，提高GVT活性。这些临床前小鼠研究将为人类研究奠定基础，在人体研究中，TCR V？谱型分析将通过分析供者T细胞和宿主肿瘤样本之间产生的体外混合淋巴细胞培养反应以及供者和宿主外周血样本(PBL)之间的同种异体反应，来检验患者体内GVT和GVHD反应的预测价值。这些体外分析将与从患者移植后获得的PBL的TCRV？谱型进行比较。比较体外肿瘤和宿主反应与体内分析的V？谱型，可以确定哪些T细胞特异性最有可能是GVH或GVT反应特异性的。

DESCRIPTION (provided by applicant): Following allogeneic blood and marrow transplantation (BMT), mature donor T cells can enhance engraftment, counteract opportunistic infections, and mount graft-versus-tumor (GVT) responses, but at the risk of developing graft-versus-host disease (GVHD). The key to the future of allogeneic BMT as immunotherapy for the treatment of cancer lies in the ability to enhance the beneficial effects of the donor T cells in mediating GVT while minimizing their capacity to cause GVHD. One approach to accomplish this goal would be to selectively deplete subsets of alloreactive T cells in the hematopoietic stem cell inoculum. In this regard, TCR V¿ repertoire analysis by CDR3-size spectratyping can be a powerful tool for the characterization of alloreactive T cell responses. The general aim of this proposal is the investigation of the immunobiology of lethal GVHD and GVT effects by concentrating on how the donor anti-host minor histocompatibility antigen (miHA) T cell repertoire develops and the broad definition of the TCR specificities involved in disease pathogenesis of the target tissues and GVT responses. To accomplish this, the B10.BR->CBA and the C57BL/6 (B6)->CXB-2, B6->BALB.B, B6->CXB-3 and B6->CXB-7 miHA-mismatched strain combination transplantation models will be utilized. Varying levels of GVHD pathogenesis are mediated by CD8+ and/or CD4+ T cells in each of these transplantation models. In addition, the role of host elements outside the hematopoietic compartment, as immune modulators for GVHD will be examined. The T cell repertoires involved in GVHD and GVT responses will be analyzed by TCR V¿ spectratyping. These latter studies will be accomplished by challenging the CBA or CXB-2 mice with host-derived murine myeloid leukemia cells (MMC6 and MME4). The spectratype analysis will be used to guide manipulation of donor T cell inocula in an effort to diminish GVHD and boost the GVT activity. These preclinical murine studies will establish the foundation for the human studies in which TCR V¿ spectratype analysis will be used to examine the predictive value for the in vivo GVT and GVHD responses from patients by analysis of in vitro mixed lymphocyte culture responses, generated between donor T cells and host tumor samples, as well as alloreactivity between donor and host peripheral blood samples (PBL). These in vitro analyses will be compared with TCR V¿ spectratyping of PBL obtained from the patient post-transplantation. Comparing V¿ spectratypes between the in-vitro tumor- and host- reactive responses with those of the in vivo analysis will allow determination of which T cell specificities are most likely to be GVH or GVT reactive-specific.