Sugito K, Inoue M, Ikeda T, Hagiwara N, Koshinaga T, Kusafuka T
Department of Pediatric Surgery, Nihon University, Tokyo, Japan.
Transplant Proc. 2007 Dec;39(10):3432-5. doi: 10.1016/j.transproceed.2007.07.083.
We investigated the extent of apoptosis in crypt cells and Peyer's patches (PPs) during small bowel allograft rejection in rats to examine the effect of FTY720 and ex vivo graft irradiation during rejection.
Orthotopic small bowel transplantations (SBT) were performed from Brown Norway (BN) rats to Lewis (LEW) rats. Four groups of SBT animals were studied on days 3, 5, and 7 after operations: untreated allograft, allograft with FTY720, allograft with irradiation, and allograft with FTY720+irradiation. Cryostat sections were prepared from the grafts, including PPs. An in situ end-labeling (ISEL) technique was used to detect apoptotic cells. Indirect immunoperoxidase staining was also performed using monoclonal antibodies against rat Fas/FasL.
The graft survival was prolonged in the FTY720-treated groups. In the FTY720-treated group, the number of ISEL-positive enterocytes was significantly down-regulated on days 3, 5, and 7 compared with the untreated allograft group. The number of ISEL-positive mononuclear cells was also significantly down-regulated compared with the untreated allograft group. The FTY720 the radiation and the FTY720+irradiation treated groups showed significantly down-regulated numbers of Fas/FasL-positive enterocytes on day 7 compared with the untreated allograft group. Fas/FasL-positive mononuclear cells were also significantly down-regulated in the allograft compared with the untreated allograft group.
FTY720 and ex vivo graft irradiation prevented up-regulation of the number of apoptotic enterocytes, lymphocytes, and Fas/FasL-positive lymphocytes, and also prolonged small bowel allograft survival. Combination FTY720 and ex vivo graft irradiation did not affect graft survival and apoptotic cell expression compared with the FTY720 only group. These findings suggest that FTY720 may prevent both rejection-associated and sepsis-induced apoptosis during the late phase of small bowel graft rejection.
我们研究了大鼠小肠同种异体移植排斥反应期间隐窝细胞和派尔集合淋巴结（PPs）中的细胞凋亡程度，以检测FTY720和排斥反应期间离体移植物照射的效果。
将棕色挪威（BN）大鼠的小肠原位移植到刘易斯（LEW）大鼠体内。在术后第3、5和7天对四组小肠移植动物进行研究：未处理的同种异体移植物、接受FTY720处理的同种异体移植物、接受照射的同种异体移植物以及接受FTY720+照射的同种异体移植物。从包括PPs在内的移植物制备低温切片。采用原位末端标记（ISEL）技术检测凋亡细胞。还使用抗大鼠Fas/FasL单克隆抗体进行间接免疫过氧化物酶染色。
FTY720处理组的移植物存活时间延长。在FTY720处理组中，与未处理的同种异体移植物组相比，第3、5和7天时ISEL阳性肠上皮细胞数量显著下调。与未处理的同种异体移植物组相比，ISEL阳性单核细胞数量也显著下调。与未处理的同种异体移植物组相比，FTY720处理组、照射处理组以及FTY720+照射处理组在第7天时Fas/FasL阳性肠上皮细胞数量显著下调。与未处理的同种异体移植物组相比，同种异体移植物中Fas/FasL阳性单核细胞数量也显著下调。
FTY720和离体移植物照射可防止凋亡肠上皮细胞、淋巴细胞以及Fas/FasL阳性淋巴细胞数量上调，还可延长小肠同种异体移植物存活时间。与仅使用FTY720组相比，联合使用FTY720和离体移植物照射对移植物存活和凋亡细胞表达无影响。这些发现表明，FTY720可能在小肠移植物排斥反应后期预防与排斥相关和脓毒症诱导的细胞凋亡。
