Non-Myeloablative Host Conditioning that Protects Against GVHD

本研究计划的目标是利用宿主调节性自然杀伤（NK）I细胞来预防移植物 抗宿主病（GVHD）和保留移植物抗淋巴瘤活性后，MHC-不匹配的骨髓 小鼠移植。特别是，我们将测试的假设，调节NK T细胞，占主导地位的 用全淋巴照射（TLI）和抗胸腺素血清（ATS）调节宿主后的T细胞亚群， 通过分泌IL-4和将供体T细胞极化为Th 2细胞因子谱来预防GVHD。的th 2 极化理论上减弱GVHD，但不干扰供体CD 8 * T细胞对BCLi肿瘤细胞的杀伤， 通过执行细胞溶解分子介导直接细胞接触细胞溶解的细胞。我们将通过以下方式来验证这个假设 确定在TLI和ATS调节的野生型宿主中观察到的针对GVHD的保护是否 在NK T细胞缺陷型CD 1d“”和Ja 281“”宿主中丢失，并且可以通过注射纯化的NK T细胞来恢复 来自野生型而非IL-4~/~宿主品系小鼠的细胞。我们还将确定是否供体CD 4 + T细胞， 分泌IL-4是保护免受GVHD和Th 2极化过程所需的。我们将测试 极化过程是否显著降低供体T细胞在宿主中的早期快速扩增 通过流式细胞术和生物发光成像测量的组织，以及前 炎性Th 1细胞因子损伤宿主组织。NK T细胞将被研究其阻断 混合白细胞反应（MLR）中供体T细胞扩增和Th 1细胞因子分泌，而 将CDS* 细胞溶解性T细胞前体分化为可杀死肿瘤细胞的效应杀伤细胞。 最后，我们将确定p53“7“和Bcl-2转基因宿主是否不能显示NK T细胞的增加， 在照射后所有T细胞中的一个细胞亚群，也不能在用 TLI和ATS。

The goal oftheresearch plan is touse host regulatory natural killer (NK) I cells toprevent graft versus host disease (GVHD) and retain graft anti-lymphoma activity after MHC-mismatched bone marrow transplantation in mice. In particular, we will test the hypothesis that regulatory NK T cells, the predominant T cell subset after conditioning hosts with total lymphoid irradiation (TLI) and anti-thymoctye serum (ATS), prevents GVHD by secreting IL-4, and polarizing donor T cells to a Th2 cytokine profile. The Th2 polarization is theorized to attenuate GVHD, but not interfere with BCLi tumor cell killing by donor CD8* T cells that mediate direct cell contact cytolysis via perform cytolytic molecules. We will test the hypothesisby determining whether protection against GVHD that is observed in TLI and ATS conditioned wild-type hosts is lost in NK T cell deficient CD1d''" and Ja281''" hosts, and can be restored by the injection of purified NK T cells from wild-type but not IL-4~/~ host strain mice. We will also determine whether donor CD4+ T cells that secrete IL-4 are required for protection against GVHD and for the Th2 polarization process. We will test whether the polarization process markedly reduces the early rapid expansion of donor T cells in the host tissues as measured by flow cytometry and bioluminescence imaging, and the early secretion of pro- inflammatory Th1 cytokines that injure host tissues. NK T cells will be studied for their capacity to block donor T cell expansion and Th1 cytokine secretion in vitro in the mixed leukocyte reaction (MLR), while permiting the differentiation of CDS* cytolytic T cell precursors into effector killer cells that can kill tumor cells. Finally, we will determine whether p53"7"and Bcl-2 transgenic hosts that fail to show an increase in the NK T cell subset among all T cells after irradiation, also fail to be protected against GVHD after conditioning with TLI and ATS.