Sugiura K, Lee S, Nagahama T, Adachi Y, Ishikawa J, Ikehara S
First Department of Pathology, Kansai Medical University, 10-15 Fumizono-cho, Moriguchi City, Osaka 570-8506, Japan.
Immunol Lett. 2001 May 1;77(1):25-30. doi: 10.1016/s0165-2478(01)00195-x.
We have previously succeeded in inducing persistent donor-specific tolerance across Mls plus multiple minor histocompatibility barriers by portal venous (p.v.) injection of donor spleen or bone marrow cells plus cyclophosphamide (CY) treatment. Microchimerism was established in the lymph-hemopoietic organs of the tolerant recipients. However, the mechanisms, particularly the roles of CY in the tolerance induction, have not been clarified. We examined the tolerance induction using other anti-mitotic agents and evaluated the in vitro proliferative responses and cytokine expression of T cells from the recipients after stimulation with donor alloantigens. The administration of not only CY but also mitomycin C (MMC) and cytosin arabinoside (Ara C) elicited a prolongation of skin graft survival. CY induced tolerance when it was administered 2 days after the p.v. injection, but not immediately or 4 days after the p.v. injection. T cells collected from the tolerant recipients showed no proliferative responses as a result of stimulation with donor alloantigens whereas the responses of T cells from non-tolerant recipients were significantly enhanced. Interferon-gamma (IFNgamma) was extensively expressed in the non-tolerant T cells from 24 to 48 h after the stimulation with donor alloantigens. In contrast, the expression of IFNgamma was observed in the tolerant T cells from 72 h after the stimulation. Also, the tolerant T cells showed the expression of interleukin-10 (IL-10) and transforming growth factor-beta 1 (TGF-beta1) from 72 h after the stimulation whereas the non-tolerant T cells did not. These data suggest that CY, when administered 2 days after the p.v. injection, induces persistent tolerance by inhibiting T helper type 1 (Th1) activity in the early period but not the Th1 activity in the later periods.
我们之前通过门静脉注射供体脾细胞或骨髓细胞并联合环磷酰胺（CY）处理，成功诱导了跨越Mls以及多个次要组织相容性屏障的持续性供体特异性耐受。微嵌合体在耐受受体的淋巴造血器官中得以建立。然而，其机制，尤其是CY在耐受诱导中的作用，尚未阐明。我们使用其他抗有丝分裂剂研究了耐受诱导情况，并评估了受体T细胞在受到供体同种异体抗原刺激后的体外增殖反应和细胞因子表达。不仅CY，丝裂霉素C（MMC）和阿糖胞苷（Ara C）的给药也能延长皮肤移植存活时间。CY在门静脉注射后2天给药时可诱导耐受，但在门静脉注射后立即给药或4天给药则不能。从耐受受体收集的T细胞在受到供体同种异体抗原刺激后无增殖反应，而未耐受受体的T细胞反应则显著增强。在受到供体同种异体抗原刺激后24至48小时，干扰素-γ（IFNγ）在未耐受的T细胞中广泛表达。相比之下，在受到刺激72小时后，在耐受的T细胞中观察到IFNγ的表达。此外，耐受的T细胞在受到刺激72小时后开始表达白细胞介素-10（IL-10）和转化生长因子-β1（TGF-β1），而未耐受的T细胞则不表达。这些数据表明，CY在门静脉注射后2天给药时，通过在早期抑制1型辅助性T细胞（Th1）活性而非后期抑制Th1活性来诱导持续性耐受。
