Hao J, Liu J, Xie S
Immunology of Department, Peking University Health Science Center, Beijing 100083, China.
Zhonghua Yi Xue Za Zhi. 2001 May 25;81(10):593-6.
To study skin allograft tolerance induced by intravenous injection of allogeneic spleen cells and intraperitoneal injection of cyclophosphamide (CP), followed by anti-TCR monoclonal antibody injections in adult recipient mice and its mechanisms.
Injecting the spleen cells of BALB/c mice (H-2(d)) were injected to C57BL/6 mice (H-2(b), B6) via the tail vein. Two days later an intraperioneal injection of cyclophosphamide was given to the B6 mice, and followed by anti-TCR alpha beta monoclonal antibody injection via the tail vein, after which skin of BALB/c mice were grafted to the tolerance-induced B6 mice. The control groups were: (1) normal B6 mice grafted with BABL/c skin; (2) normal B6 mice grafted with KM skin; (3) B6 mice treated with SC + CP + anti-TCR alpha beta monoclonal antibody administration and grafted with BALB/c skin allograft; (4) B6 mice treated as group 3, and grafted with KM skin instead of BALB/c skin. Detection of chimerism, adoptive transfer assay and the effect of exogenous IL-2 on MLR were performed to explore tolerance mechanisms. Group data in each experiment were compared with Group's t-test.
The survival of BALB/c skin allograft in recipient B6 mice was 66.3 days, P < 0.001 compared with the other three groups. The results of FACS analysis showed that a mixed microchimerism was developed in the thymus and spleen of tolerant mice. The percentage of cells of BALB/c origin in the thymus on day 15, 35, and 70 after induction of tolerance was 2.67%, 1.61%, and 0.47%, and in the spleen is 7.66%, 5.99%, and 3.87%, respectively. No suppressive activity in the spleen cells of tolerant mice was observed by in vivo and in vitro cell transfer experiments. MLR of spleen cells in the tolerant B6 mice to spleen cells of BALB/c origin was specifically suppressed, which was 4 725 +/- 406 cpm by (3)H-TdR incorporation. However, the specific inhibition of MLR of tolerant B6 mice could be partially reversed (P < 0.01), the (3)H-TdR incorporation reached 18 175 +/- 3 642 cpm by adding exogenous IL-2.
Chimerism and clonal anergy are the main mechanisms of the tolerance.
研究成年受体小鼠经静脉注射同种异体脾细胞和腹腔注射环磷酰胺（CP），随后注射抗TCR单克隆抗体诱导的皮肤同种异体移植耐受及其机制。
将BALB/c小鼠（H-2(d)）的脾细胞经尾静脉注射到C57BL/6小鼠（H-2(b)，B6）体内。两天后给B6小鼠腹腔注射环磷酰胺，随后经尾静脉注射抗TCRαβ单克隆抗体，之后将BALB/c小鼠的皮肤移植到诱导耐受的B6小鼠身上。对照组为：（1）移植BABL/c皮肤的正常B6小鼠；（2）移植KM皮肤的正常B6小鼠；（3）经脾细胞+环磷酰胺+抗TCRαβ单克隆抗体处理并移植BALB/c皮肤同种异体移植物的B6小鼠；（4）按第3组处理、但移植KM皮肤而非BALB/c皮肤的B6小鼠。进行嵌合体检测、过继转移试验及外源性白细胞介素-2对混合淋巴细胞反应（MLR）的影响试验以探讨耐受机制。各实验中的组间数据采用成组t检验进行比较。
受体B6小鼠体内BALB/c皮肤同种异体移植物的存活时间为66.3天，与其他三组相比，P<0.001。流式细胞术分析结果显示，耐受小鼠的胸腺和脾脏中出现了混合微嵌合体。诱导耐受后第15、35和70天，胸腺中BALB/c来源细胞的百分比分别为2.67%、1.61%和0.47%，脾脏中分别为7.66%、5.99%和3.87%。体内和体外细胞转移实验均未观察到耐受小鼠脾细胞的抑制活性。耐受的B6小鼠脾细胞对BALB/c来源脾细胞的MLR受到特异性抑制，通过掺入（3）H-TdR检测为4725±406 cpm。然而，耐受的B6小鼠MLR的特异性抑制可被部分逆转（P<0.01），加入外源性白细胞介素-2后，（3）H-TdR掺入量达到18175±3642 cpm。
嵌合体和克隆无能是耐受的主要机制。
