GENETICS AND MECHANISMS OF DLI EFFECTS FOLLOWING NON-MYELOBLATIVE HCT

非清髓性造血细胞移植（HCT）后延迟供体白细胞输注 (DLI)是治疗血液恶性肿瘤包括白血病和 淋巴瘤然而，这种方法的主要局限性包括移植物失败、移植物抗宿主的风险。 疾病，（GVHD）和感染。MGH MHC-近交系小型猪为以下研究提供临床前模型： 移植生物学对HCT的反应与人类相似。初步数据显示， 一种新的、最低限度的骨髓抑制准备方案在高剂量给药后导致稳定的多谱系嵌合体 单倍体相合的HCT，而不引起GVHD。在本建议中，我们的目标是1）确定免疫学 参与控制hbst抗移植物（HVG）和GVH反应的机制， 在这个模型中没有GVHD穿过MHC屏障。这些研究将与以下机构密切合作进行： 项目1和项目2旨在扩大啮齿动物模型中的机制研究。然后我们将优化猪 模型，以促进翻译本协议的临床和分析的重要性，特定的遗传 移植物抗宿主病（GVHD）和单倍性I类和II类，仅I类，仅II类的差异 后续DLI。与项目4合作，我们将测试新的策略，以提高干细胞收获 在通过甲状旁腺激素（PTH）刺激进行细胞因子动员后。增加茎的数量 在PTH刺激和细胞因子动员后，白细胞去除产物中的细胞可以使稳定的 使用较低剂量的细胞移植在临床上更容易实现。希望这些结果 研究将允许开发针对嵌合患者使用DLI的定制方法，具体取决于 与捐赠者的HLA差异此外，我们计划3）进一步开发猪模型， 直接评估HCT和DLI的移植物抗肿瘤效应。为此，我们将建立肿瘤细胞 来自近交系小型猪的肿瘤细胞系，并使这些肿瘤细胞系适应猪体内生长。与 最近可获得的组织相容性小型猪，以及来自这些高度近交系的肿瘤系 动物，我们有独特的机会在临床前大型动物模型中开发可移植肿瘤。 这些研究可以为未来的免疫治疗方法提供基础。 血液恶性肿瘤，可以转化为人类疾病的治疗。

Non-myeloablative hematopoietic cell transplantation (HCT) followed by delayed donor leukocyte infusion (DLI) is a promising immunotherapeutic approach to treat hematologic malignancies including leukemias and lymphomas. Major limitations of this approach, however, include the risks of graft failure, graft-versus-host disease, (GVHD) and infection. MGH MHC-inbred miniature swine provide a pre-clinical model for studies of transplantation biology with responses to HCT resembling those of humans. Preliminary data suggest that a novel, minimally myelosuppressive preparative regimen leads to stable multilineage chimerism following highdose haploidentical HCT, without causing GVHD. In this proposal we aim to 1) determine the immunological mechanisms involved in controlling hbst-versus-graft (HVG) and GVH responses that allow engraftment without GVHD across MHC barriers in this model. These studies will be performed in close collaboration with Projects 1 and 2 to extend the mechanistic studies in rodent models. We will then 2) optimize the swine model to facilitate translation of this protocol to the clinic and analyze the importance of specific genetic disparities (haploidentical class I and II, class I only, class II only) on engraftment, GVHD and the effects of subsequent DLI. In collaboration with Project 4, we will test novel strategies to improve stem cell harvests following cytokine mobilization through parathyroid hormone (PTH) stimulation. Increased numbers of stem cells in the leukapheresis product following PTH stimulation and cytokine mobilization may enable stable engraftment using lower doses of cells more easily attainable in the clinic. It is hoped that results of these studies will permit the development of tailored approaches to the use of DLI in chimeric patients depending on their HLA disparities from the donor. In addition, we plan to 3) further develop the swine model to allow direct assessment of graft-versus-tumor effects of HCT and DLI. For this purpose, we will establish tumor cell lines derived from inbred miniature swine and adapt these tumor lines for in vivo growth in pigs. With the recent availability of histocompatible miniature swine, and tumor lines derived from these highly inbred animals, we have the unique opportunity to develop transplantable tumors in a preclinical large animal model. These studies could provide a foundation for future immunotherapeutic approaches for the treatment of hematological malignancies that may be translated toward treatment of human disease.