HUMAN CTL-MEDIATED INJURY OF GRAFT ENDOTHELIAL CELLS

人类 CTL 介导的移植物内皮细胞损伤

• 批准号: 6490639
• 负责人: JORDAN S POBER
• 金额: $ 35.42万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-01-10 至 2004-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6490639
• 关键词: BCL2 gene /protein; CD44 molecule; MHC class I antigen; biological signal transduction; cytokine; cytotoxic T lymphocyte; gene expression; homologous transplantation; integrins; interleukin 11; laboratory mouse; selectins; transplant rejection; vascular endothelium

Cytolytic T lymphocytes (CTL) have been identified as major effector cells of acute allograft rejection and vascular endothelial cells (EC) are the primary cellular targets of allograft injury. Injury to graft arterial BC (endothelialitis Or type II rejection) is both a harbinger of therapy-resistant acute rejection and a potential precursor lesion for chronic rejection. Rejecting cardiac allografts contain endothelial-specific alloreactive CTL that do not kill donor leukocytes. The investigators hypothesize that the CTL which mediate endotheliaiitis are specific for graft BC and may differ from conventional alloreactive CTL, explaining the prognostic distinction hetween acute parenchymal (type I) and vascular (type II) rejection. The investigators have found that cultured human EC stimulate generation of EC-specific alloreactive CTL in vitro while suppressing the development of conventional CTL. They also have developed novel models, utilizing huPBL-SCID/beige mice, to produce human CTL-mediated injury to human skin microvessel or arterial allografts in vivo. The investigators have optimized conditions for stable retroviral transduction of exogenous genes into human EC and have developed a synthetic microvesse1 system for transplanting transduced EC into SCID/beige mice. Finally, they have discovered that the cytokine IL-11 can make human EC resistant to lysis by CTL. The specific aims of the proposal are: (1) to identify signals (costimulators and cytokines) provided by EC that cause the development of EC-specific CTL while suppressing conventional CTL and to determine if EC-mediated effects are also observed in vivo in various huPBL/SCID beige mouse models; (2) to determine the basis of EC-specific recognition, evaluating the relative contributions of EC-specific peptides, of EC MHC class Ib molecules, and of EC accessory interactions (e.g., involving selectins, integrins or CD44); and (3) to determine the basis of the IL- 11 cytoprotective effect and to evaluate the protective effects of bcl-2 and survivin overexpression in vitro and in vivo. The results of these studies will advance knowledge about EC-CTL interactions in transplantation and provide a basis for novel immunomodulatory or gene-based therapies to improve graft outcome.

溶细胞性T淋巴细胞（CTL）已被确定为急性同种异体移植排斥的主要效应细胞，血管内皮细胞（EC）是同种异体移植损伤的主要细胞靶标。移植动脉 BC 损伤（内皮炎或 II 型排斥反应）既是治疗抵抗性急性排斥反应的先兆，也是慢性排斥反应的潜在先兆病变。排斥心脏同种异体移植物含有内皮特异性同种异体反应性 CTL，不会杀死供体白细胞。研究人员假设介导内皮炎的 CTL 对移植物 BC 具有特异性，并且可能与传统的同种异体反应性 CTL 不同，这解释了急性实质（I 型）和血管（II 型）排斥之间的预后区别。研究人员发现，培养的人类 EC 在体外刺激 EC 特异性同种异体 CTL 的产生，同时抑制传统 CTL 的发育。他们还开发了新的模型，利用 huPBL-SCID/beige 小鼠，在体内对人体皮肤微血管或同种异体动脉移植物产生人类 CTL 介导的损伤。研究人员优化了外源基因逆转录病毒稳定转导至人类 EC 的条件，并开发了一种合成微血管 1 系统，用于将转导的 EC 移植到 SCID/米色小鼠中。最后，他们发现细胞因子IL-11可以使人类EC抵抗CTL的裂解。该提案的具体目标是：(1) 识别 EC 提供的信号（共刺激剂和细胞因子），这些信号导致 EC 特异性 CTL 的发展，同时抑制常规 CTL，并确定在各种 huPBL/SCID 米色小鼠模型体内是否也观察到 EC 介导的效应； (2) 确定 EC 特异性识别的基础，评估 EC 特异性肽、EC MHC Ib 类分子和 EC 辅助相互作用（例如，涉及选择素、整联蛋白或 CD44）的相对贡献； (3)确定IL-11细胞保护作用的基础并评价bcl-2和survivin过表达的体外和体内保护作用。这些研究的结果将增进对移植中 EC-CTL 相互作用的了解，并为新型免疫调节或基于基因的疗法改善移植结果提供基础。