Sefrioui H, Billiau A D, Waer M
Laboratory of Experimental Transplantation, University of Leuven, Belgium.
Transplantation. 2000 Jul 27;70(2):348-53. doi: 10.1097/00007890-200007270-00020.
Previous studies have demonstrated that delayed donor leukocyte infusion (DLI) can increase graft-versus-leukemia (GVL) without increasing graft-versus-host-disease (GVHD) in MHC mismatched bone marrow (BM) chimeras. In our report, the immune status of minor antigen mismatched BM chimeras given DLI was studied. Particularly the role of donor ASGM1 positive or T cells in the graft-versus-leukemia effect (GVL) was investigated.
AKR mice (H2k, Mls1a, Thy1.1) received TBI (9,5 Gy) and T cell-depleted (TCD) C3H (H2k, Mls2a, Thy1.2) BM alone (BM chimeras), or TCD BM together with immunocompetent C3H spleen cells at the time of BM transplantation (BM+SP chimeras), or TCD BM and 3 weeks later C3H spleen cells (DLI chimeras). Chimerism and T lymphocyte subsets were scored using FACS and anti-Thy, anti-Vbeta6, anti-IL2-beta receptor, anti-CD4, anti-CD3, and anti-CD8 mAbs. Leukemia challenge consisted of 5 x 10(6) AKR T cell lymphoma (BW4157) cells injected i.v. ASGM1 positive (ASGM1+) cells and T cells were depleted using anti-ASGM1 or anti-Thy1.2 antibodies, respectively. Immune tolerance was studied using MLR and CML tests.
BM + SP chimeras developed acute and lethal GVHD, whereas DLI chimeras were totally free from GVHD. In DLI chimeras, host-reactive cytotoxic T cells (CTL) could not be induced and host-reactive CD8Vbeta6 cells were deleted whereas CD4Vbeta6 cells and MLR reactivity persisted temporarily. In contrast, in BM+SP chimeras, anti-host CTL were easily generated and an expansion of both host-reactive CD8Vbeta6 and CD4Vbeta6 T cells was found as well as high anti-host MLR reactivity. Depletion of either ASGM1 + cells or T cells from the DLI inoculum resulted in an abrogation of GVL reactivity, suggesting that both cell populations were involved in the protection against BW4157 leukemia. Three weeks after DLI, the GVL effect waned which correlated with the disappearance of host-reactive CD4 cells and MLR reactivity.
In minor antigen mismatched BM chimeras, anti-host reactivity after DLI is characterized by (1) an absence of clinical GVHD, (2) clonal deletion of host-reactive CD8 cells, (3) an absence of anti-host CTL induction, and ( 4) a temporary persistence of host-reactive CD4 T cells and of MLR reactivity. In addition, either donor ASGM1+ cells or an interaction between these cells and T cells contribute to the GVL effect.
先前的研究表明，在主要组织相容性复合体（MHC）不匹配的骨髓嵌合体中，延迟供体白细胞输注（DLI）可增强移植物抗白血病（GVL）效应，而不增加移植物抗宿主病（GVHD）。在本报告中，我们研究了接受DLI的次要抗原不匹配骨髓嵌合体的免疫状态。特别研究了供体ASGM1阳性细胞或T细胞在移植物抗白血病效应（GVL）中的作用。
AKR小鼠（H2k、Mls1a、Thy1.1）接受全身照射（TBI，9.5 Gy），并单独接受去除T细胞（TCD）的C3H（H2k、Mls2a、Thy1.2）骨髓（骨髓嵌合体），或在骨髓移植时接受TCD骨髓与具有免疫活性的C3H脾细胞（BM+SP嵌合体），或TCD骨髓并在3周后接受C3H脾细胞（DLI嵌合体）。使用荧光激活细胞分选术（FACS）以及抗Thy、抗Vbeta6、抗IL2-β受体、抗CD4、抗CD3和抗CD8单克隆抗体对嵌合状态和T淋巴细胞亚群进行评分。白血病攻击包括静脉注射5×10⁶个AKR T细胞淋巴瘤（BW4157）细胞。分别使用抗ASGM1或抗Thy1.2抗体去除ASGM1阳性（ASGM1+）细胞和T细胞。使用混合淋巴细胞反应（MLR）和细胞毒性淋巴细胞（CML）试验研究免疫耐受性。
BM+SP嵌合体发生急性致死性GVHD，而DLI嵌合体完全没有GVHD。在DLI嵌合体中，无法诱导出宿主反应性细胞毒性T细胞（CTL），宿主反应性CD8Vbeta6细胞被清除，而CD4Vbeta6细胞和MLR反应性暂时持续存在。相比之下，在BM+SP嵌合体中，很容易产生抗宿主CTL，并且发现宿主反应性CD8Vbeta6和CD4Vbeta6 T细胞均有扩增以及高抗宿主MLR反应性。从DLI接种物中去除ASGM1+细胞或T细胞均导致GVL反应性丧失，表明这两种细胞群体均参与了对BW4157白血病的保护。DLI后3周，GVL效应减弱，这与宿主反应性CD4细胞和MLR反应性的消失相关。
在次要抗原不匹配的骨髓嵌合体中，DLI后的抗宿主反应具有以下特征：（1）无临床GVHD；（2）宿主反应性CD8细胞的克隆性清除；（3）无抗宿主CTL诱导；（4）宿主反应性CD4 T细胞和MLR反应性的暂时持续存在。此外，供体ASGM1+细胞或这些细胞与T细胞之间的相互作用有助于GVL效应。
