Levy R B, Cotterell A H, Jones M, Malek T R
Department of Microbiology and Immunology, University of Miami School of Medicine, FL 33101.
J Immunol. 1988 Mar 15;140(6):1717-25.
To investigate the effects of graft-vs-host reactions (GvHR) on cells in a central lymphoid compartment, GvHR were induced across class I/II or class II only major histocompatibility complex differences utilizing the parent into nonirradiated F1 hybrid (P----F1) model. Thymocytes were subsequently examined during the acute stage of GvHR for the expression of Lyt-2, L3T4, and Ly-6 cell surface molecules. Class I/II "suppressive" GvHR resulted in a dramatic decrease (greater than 85%) in total thymocyte numbers by 2 wk after parental cell injection. Although a dramatic decrease in the percentages of Lyt-2 (85%----30%) and L3T4 (95%----50%) expression was observed, the percentage of thymocytes expressing Ly-6 was markedly increased compared to uninjected controls (5%----greater than 80%). This increased percentage was not due solely to a selective loss of Ly-6 negative cells from the thymus, since the actual number of Ly-6 positive cells was greater in GvHR mice than in controls. Class II GvHR during the same time interval resulted in a less dramatic decrease (20 to 60%) in total thymocyte numbers. In addition, the effect on the percentages of Lyt-2 (85%----approximately 70%) and L3T4 (95%----approximately 85) expression was subtle and transient. However, intrathymic Ly-6 expression was again clearly enhanced (5%----20 to 30%). Class I/II "proliferative" or "stimulatory" GvHR differ from "suppressive" reactions in that they are characterized by stimulatory pathologic symptoms and the appearance of autoimmune abnormalities. Such GvHR were found to result in minimal alteration of total thymocyte numbers. Similarly, the percentage expression of Lyt-2 and L3T4 was marginally affected. However, the percentage of Ly-6 expression was increased from 5%----20 to 30% and thus these intrathymic lymphocyte profiles more closely resemble those of class II as compared to class I/II "suppressive" GvHR. The present findings therefore demonstrate that major histocompatibility complex differences alone do not necessarily determine the effects of GvHR on recipient thymocytes and that Ly-6 is a useful marker for the early detection of GvHR-associated immunologic events.
为了研究移植物抗宿主反应（GvHR）对中枢淋巴区室中细胞的影响，利用亲代到未受照射的F1杂种（P→F1）模型，在I类/II类或仅II类主要组织相容性复合体差异上诱导GvHR。随后在GvHR急性期检查胸腺细胞中Lyt-2、L3T4和Ly-6细胞表面分子的表达。I类/II类“抑制性”GvHR导致亲代细胞注射后2周时总胸腺细胞数量急剧减少（超过85%）。虽然观察到Lyt-2（85%→30%）和L3T4（95%→50%）表达百分比急剧下降，但与未注射对照相比，表达Ly-6的胸腺细胞百分比显著增加（5%→超过80%）。这种增加的百分比并非仅仅由于胸腺中Ly-6阴性细胞的选择性丢失，因为GvHR小鼠中Ly-6阳性细胞的实际数量比对照小鼠中的多。同一时间间隔内的II类GvHR导致总胸腺细胞数量减少幅度较小（20%至60%）。此外，对Lyt-2（85%→约70%）和L3T4（95%→约85%）表达百分比的影响细微且短暂。然而，胸腺内Ly-6表达再次明显增强（5%→20%至30%）。I类/II类“增殖性”或“刺激性”GvHR与“抑制性”反应不同，其特征在于刺激性病理症状和自身免疫异常的出现。发现此类GvHR导致总胸腺细胞数量变化最小。同样，Lyt-2和L3T4的表达百分比受到的影响很小。然而，Ly-6表达百分比从5%→20%至30%增加，因此与I类/II类“抑制性”GvHR相比，这些胸腺内淋巴细胞谱更类似于II类。因此，目前的研究结果表明，仅主要组织相容性复合体差异不一定决定GvHR对受体胸腺细胞的影响，并且Ly-6是早期检测GvHR相关免疫事件的有用标志物。
