The role of TRAIL in bone marrow transplantation

描述（由申请人提供）：供体T细胞在以下方面发挥关键作用： 异基因骨髓移植（BMT）。供体来源的细胞毒性T细胞 主要负责移植物抗肿瘤（GVT）活性， 移植物抗宿主病（GVHD）。细胞毒性T细胞可以发挥其细胞溶解作用， 通过至少两种效应物途径的活性：Fas配体（FasL）和 穿孔素/颗粒酶。这两种细胞毒性效应物途径，除了TNF （已被提出作为第三个T细胞效应途径），发挥重要作用， 在GVHD和GVT的发展中的作用。我们在小鼠模型中的最新研究 和其他人已经证明了这些细胞溶解途径的不同用途， GVHD、GVT和供体白细胞输注（DLI）中的供体T细胞。这表明 细胞溶解途径的选择性抑制可能代表了一种新的 将GVT与GVHD分开的策略。肿瘤坏死因子相关 凋亡诱导配体（TRAIL）是TNF超家族的成员， 包括FasL和TNF。TRAIL已被证明可诱导肿瘤细胞凋亡 而不影响非转化细胞，然而它在健康和疾病中的作用 仍是未知数在本申请中，我们提出剖析 TRAIL在GVHD、GVT和供体移植中的应用 TRAIL缺陷型小鼠和临床中的中和性抗TRAIL抗体 相关鼠BMT模型。在具体目标1中，我们建议研究 a）TRAIL缺陷型B6（B6.TRAIL-/-）供体细胞，或B）体内 施用中和性抗TRAIL抗体对GVHD发病率的影响， 死亡率和特异性GVHD相关器官病理学。我们将研究 TRAIL在受者GVHD病理生理中的作用 T细胞扩增和活性、CD 4/8比率、血清细胞因子水平（IL-1、IL-12、 TNF、IFN）、血清内毒素水平和巨噬细胞活化。该分析 将对以下受体重复进行：a）接受了亚致死剂量的 照射以确定移植物排斥，或B）已接种肿瘤 细胞在BMT的时间，以分析的重要性，肿瘤坏死因子相关凋亡诱导配体通路的GVT (and DLI）与GVHD相关。在具体目标2中，我们将研究 受体中TRAIL缺乏及其对GVHD发展的影响。 在具体目标3中，我们提出产生在以下方面具有多重缺陷的小鼠： 溶细胞途径这些小鼠将用于类似的实验， 目的1和2中所述的目的，以发现与本发明的化合物的任何冗余、协同作用或拮抗作用。 这些细胞溶解途径在GVHD、GVT和移植中的作用。最后，具体 目的4我们提出通过过表达TRAIL来增强GVT活性 (by腺病毒介导的递送）。这些研究可以提供 更好地理解TRAIL通路在（a）T （B）BMT后的GVHD、GVT和移植， 可以立即应用于临床。

DESCRIPTION (provided by applicant): The donor T cell plays a pivotal role in allogeneic bone marrow transplantation (BMT). Cytotoxic T cells of donor origin are primarily responsible for graft-versus-tumor (GVT) activity and graft-versus-host-disease (GVHD). Cytotoxic T cells can exert their cytolytic activity through at least two effector pathways: Fas ligand (FasL) and perforin/granzyme. These two cytotoxic effector pathways, in addition to TNF (which has been proposed as a third T cell effector pathway), play an important role in the development of GVHD and GVT. Recent studies in murine models by us and others have demonstrated a differential use of these cytolytic pathways by donor T cells in GVHD, GVT and donor leukocyte infusion (DLI). This suggests that the selective inhibition of a cytolytic pathway could represent a novel strategy for the separation of GVT from GVHD. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a member of the TNF superfamily, which includes FasL and TNF. TRAIL has been shown to induce apoptosis of tumor cells without affecting nontransformed cells, however its role in health and disease is still largely unknown. We propose in this application to dissect the role of TRAIL in GVHD, GVT, and donor engraftment y using recently generated TRAIL-deficient mice and neutralizing anti-TRAIL antibodies in clinically relevant murine BMT models. In Specific Aim 1 we propose to study the effects of a) TRAIL-deficient B6 (B6.TRAIL-/-) donor cells, or b) in vivo administration of a neutralizing anti-TRAIL antibody on GVHD morbidity and mortality and specific GVHD-associated organ pathology. We will study the role of TRAIL in the pathophysiology of GVHD in the recipients by analysis of donor T cell expansion and activity, CD4/8 ratio, serum cytokine levels (IL-1, IL-12, TNF, IFN), serum endotoxin levels, and macrophage activation. This analysis will be repeated with recipients which either a) have received sublethal irradiation to determine graft rejection, or b) have been inoculated with tumor cells at the time of BMT to analyze the importance of the TRAIL pathway for GVT (and DLI) in relation to GVHD. In Specific Aim 2 we will study the effects of TRAIL-deficiency in the recipient and its effects on the development of GVHD. In Specific Aim 3 we propose to generate mice with multiple deficiencies in the cytolytic pathways. These mice will be used for similar experiments as described in Aims 1 and 2 to discover any redundancy, synergy or antagonism of these cytolytic pathways in GVHD, GVT, and engraftment. Finally, in Specific Aim 4 we propose to enhance GVT activity through the overexpression of TRAIL (by adenovirus-mediated delivery) in donor T cells. These studies could provide a better mechanistic understanding of the role of the TRAIL pathway in (a) T cell cytotoxicity in vivo, and (b) GVHD, GVT and engraftment after BMT, which could have immediate clinical applicability.