ALTERNATE MARROW DONORS

该项目的目标是增加获得正常捐赠者的机会 用于缺乏人类白细胞抗原-1的患者的造血干细胞移植 相同的兄弟姐妹捐赠者，并提高安全性和有效性 这些移植用于治疗血液病患者 恶毒。来自可变和非变种供者的移植 有时未被发现的人类白细胞抗原不匹配有更高的发病率 以及与移植相关的死亡率(TRM)，因为更严重的移植物- 抗宿主病(GVHD)优于人类白细胞抗原相合同胞移植。 本项目四个具体目标中概述的研究是有针对性的 改进供者配型的方法和标准，减少GVHD 和TRM，并理解长期免疫的本质 在不匹配和无关的人类白细胞抗原中经常出现的缺陷 捐赠者移植。DNA分型技术的进步已经 使我们能够识别以前未被识别的人类白细胞抗原基因变异 发生在患者和他们的单倍体相同或无关的患者之间 捐赠者。在这里提出的研究中，我们将确定 人类白细胞抗原-A、B、C、DQ和DP等位基因错配是安全的 在不显著增加严重移植物抗宿主病风险的情况下耐受，以及 我们将更好地定义人类白细胞抗原不匹配和 更强的移植物抗白血病(GVL)效应的可能性可能是 有益的。将进行临床试验以确定TRM是否 可以通过提高植入率和质量来减少 使用生长因子动员的外周血干细胞(PBSC)。新的 人类白细胞抗原不相合骨髓选择性T细胞去除(TCD)方法 或来自单倍体相同的亲属和非亲属捐赠者的外周血干细胞移植 接受检查以确定这种预防GVHD的方法是否将 允许我们安全地为患者进行这种移植 找不到最佳的人类白细胞抗原匹配。实验室研究是 建议研究移植后T细胞的动力学和多样性 细胞重建，尤其是接受TCD干细胞移植的患者 分析T细胞受体(TCR)VB基因家族的表达 利用逆转录酶和聚合酶链式反应 (聚合酶链式反应)扩增单个TCR转录本。的大小变化 由重组VDJ片段编码的TCR的CDR3区将被 通过谱型分析将单个TCR克隆类型识别为 估计克隆多样性和鉴定寄主反应性T细胞的方法 可能参与移植物抗宿主病的细胞克隆。该方法可以提供 一种客观的手段来监测 免疫抑制疗法在防治移植物抗宿主病中的作用 并可能有助于确定耐受性何时发生，患者可以 安全地退出免疫抑制治疗。

The goal of this project is to increase access to normal donor hematopoietic stem cell transplants for patients who lack an HLA- identical sibling donor, and to improve the safety and efficacy of these transplants as therapy for patients with hematological malignancy. Transplants from alternative donors with variable and sometimes undetected HLA mismatching have a higher risk of morbidity and transplant-related mortality (TRM) due to more severe graft- versus-host-disease (GVHD) than HLA identical sibling transplants. Studies outlined in the four specific aims of this project are directed to improving methods and criteria for donor matching, reducing GVHD and TRM, and understanding the nature of the prolonged immune deficiency that frequently occurs in HLA mismatched and unrelated donor transplants. Advances in DNA-based typing technology has allowed us to identify previously unrecognized HLA genetic variations that occur between patients and their haploidentical or unrelated donor. In the studies proposed here we will determine the degree of mismatching for HLA-A,B,C,DQ and DP alleles that can be safely tolerated without significantly increasing the risk of severe GVHD, and we will better define the situations where HLA mismatching and the potential for a stronger graft-versus-leukemia (GVL) effect may be beneficial. A clinical trail will be undertaken to determine if TRM might be reduced by improving the rate and quality of engraftment using growth factor-mobilized peripheral blood stem cells (PBSC). New methods for selected T-cell depletion (TCD) of HLA mismatched marrow or PBSC grafts from haploidentical related and unrelated donors will be examined to determine if this approach to GVHD prevention will allow us to safely undertake these kind of transplants for patients unable to find an optimal HLA match. Laboratory studies are proposed to examine the kinetics and diversity of posttransplant T- cell reconstitution especially in patients receiving TCD stem cell grafts by analyzing the expression of T-cell receptor (TCR) VB gene families using reverse-transcriptase (RT) and the polymerase chain reaction (PCR) to amplify individual TCR transcripts. The size variation of the CDR3 region of the TCR encoded by recombinant VDJ segments will be analyzed by spectratyping to identify individual TCR clonotypes as a means for estimating clonal diversity and identifying host-reactive T- cell clones that may be involved in GVHD. This method may provide an objective means for monitoring the effectiveness of immunosuppression therapy in the prevention and treatment of GVHD, and may help determine when tolerance has occurred and patients can be safely withdrawn from immunosuppression therapy.