MANIPULATION OF GVL/GVH REACTIONS IN ALLOGENEIC BMT

异基因骨髓移植被认为是治愈的 白血病在一定程度上是通过具有免疫能力的供体细胞的作用来实现的。这个 异基因骨髓移植的抗白血病或“移植物抗白血病(GVL)”效应是一种 针对肿瘤疾病的免疫反应性的戏剧性例子， 以及成功使用异基因骨髓移植治疗的潜在好处 恶性证明有理由进行彻底的分析，以了解和 操纵反应。GVL效应通常与 移植物抗宿主病(GVHD)，但GVL与 反应和临床GVHD是有争议的。有临床和非临床的 GVL反应独立于GVHD的实验证据。 小鼠模型和体外技术提供了一个框架， GVH和GVL反应的动态平衡概念化和研究 在人类身上。在这份修订后的提案中，我们寻求评估以下方法 使用容易掌握的策略来操纵这些反应 在白血病患者身上完成。这项研究的最终目标是 (1)制定和测试治疗白血病宿主的战略，同时 实现长期生存和(Ii)提高治疗的安全性和有效性 以使更多的患者能够得到成功的治疗。要实现这些目标 目标，成熟的异基因骨髓移植小鼠模型将被用于 在不损失GVL的情况下降低GVH反应性的测试策略 在必要时，在没有GVHD的情况下，增强GVL的反应性和效果。我们 建议检验三个主要假说：(1)选择性体外 BM疫苗中T细胞亚群的耗尽可以显著改善 异基因骨髓移植后的长期无白血病存活率；(2)GVH 可以在体内调节反应性，而不会失去GVL效应 异基因骨髓移植后应用MoAbs；以及(3)无效的GVL 白介素2+CD8+T细胞可增强反应，延迟反应 供者淋巴细胞输注或免疫增强剂注射 剂量的抗CD3摩押。三种异基因骨髓移植小鼠模型的建立 供者和宿主之间不同程度的免疫遗传差异将是 使用。供体嵌合的动力学和程度将通过FLOW进行评估 细胞学分析。将使用分子探针来监测 白血病的持久性以及生物检测。不同前置处理的效果 和骨髓移植后对供者-宿主耐受性发展的干预 骨髓移植嵌合体将使用体外和体内相结合的方法来确定 分析，包括极限稀释分析。拟议的研究将 帮助确定值得进一步评估的策略和试剂 临床BMT以及在使用前需要修改的BMT。

Allogeneic bone marrow transplantation is thought to be curative in leukemia, in part, through the action of immunocompetent donor cells. The antileukemia or "graft-vs-leukemia (GVL) effect of allogeneic BMT is a dramatic example of immunological reactivity against neoplastic disease, and the potential benefit from successful use of allogeneic BMT to treat malignancy justifies a thorough analysis in order to understand and manipulate the reaction. The GVL effect usually occurs in association with graft-vs-host disease (GVHD), but the precise relationship between the GVL reaction and clinical GVHD is controversial. There is clinical and experimental evidence for a GVL reaction that is independent of GVHD. Murine models and in vitro techniques provide a framework in which to conceptualize and study the dynamic balance between GVH and GVL reactions in man. In this revised proposal, we seek to evaluate methods to manipulate these reactions using strategies that can be readily accomplished in leukemia patients. The ultimate goals of this research are (i) to develop and test strategies for curing leukemic hosts while achieving long-term survival and (ii) to improve the safety and efficacy of BMT so that more patients can be treated successfully. To achieve these goals, well established murine models of allogeneic BMT will be used to test strategies for decreasing GVH reactivity without loss of the GVL effect and increasing GVL reactivity without GVHD when necessary. We propose to test three major hypotheses: (1) that selective ex vivo depletion of T-cell subsets in the BM inoculum can significantly improve long-term, leukemia-free survival after allogeneic BMT; (2) that GVH reactivity can be regulated in vivo without loss of the GVL effect using MoAbs administered after allogeneic BMT; and (3) that an ineffectual GVL reaction can be enhanced by interleukin-2 + CD8+ T-cells, by delayed infusion of donor lymphocytes, or by administration of immunoenhancing doses of anti-CD3 MoAb. Three murine models of allogeneic BMT with differing degrees of immunogenetic disparity between donor and host will be used. The kinetics and extent of donor chimerism will be assessed by flow cytometric analysis. Molecular probes will be used to monitor the persistence of leukemia along with bioassays. The effect of various pre- and post-BMT interventions on the development of donor-host-tolerance in BMT chimeras will be determined using a combination of in vitro and in vivo assays, including limiting dilution analysis. The proposed studies will help identify strategies and reagents that merit further evaluation in clinical BMT as well as those that require modification before use.