FTY720对小肠移植物中淋巴细胞及单核细胞浸润的影响

目的：研究FTY720对同种异体小鼠小肠移植排斥反应的作用及可能机制。方法：以C3H小鼠（H-2k）为供者，C57BL/6小鼠(H-2b）为受者，行异位小肠移植。分别建立FTY720治疗组、空白对照组及同系移植组，在移植后6 d与12 d进行组织学观测评定排斥分数，流式细胞术分析移植物肠系膜淋巴结（MLN）、派氏结（PP）、粘膜上皮细胞间淋巴组织（IEL）与固有层淋巴组织（LPL）中淋巴细胞中受者淋巴细胞及单核细胞浸润情况。结果：FTY720在移植后6 d可有效抑制排斥反应，但在移植后14 d，排斥反应仍可发生在空白对照组，移植后6 d移植物内受者淋巴细胞基本取代供者细胞；而在FTY720治疗组，受者淋巴细胞进入移植物的速度及数量明显减缓，包括CD4+与CD8+ T细胞，以及CD19+ B细胞。受者来源的γδT淋巴细胞也显著减少。FTY720对Gr1+CD11b+单核细胞系也有一定的抑制作用。结论：FTY720可通过减少受者淋巴细胞及单核细胞进入移植小肠，起到缓解排斥反应的作用。

The effects of FTY720 on lymphocytes and monocytes in mouse intestinal transplantation

AIM：To test the effects of FTY720 on mouse intestinal allografts.METHODS：C3H mice（H-2k）were used as donor and C57BL/6 mice (H-2b) as recipients.FTY720 group,allogeneic control group and isogeneic control group were set up.6 and 14 days after transplantation,murine intestinal grafts were harvested for histologic assessment.Lymphocytes were collected from mesenteric lymph nodes (MLN),Peyer’s patch (PP),lamina propria lymphocytes (LPL) and intraepithelial lymphocytes (IEL) in the graft,then were analyzed by cytometry.RESULTS：Rejection was inhibited in FTY720 group at the 6th post-transplant day,although not at the 14th day.Recipient CD4+ and CD8+ T cells,CD19+ B cells,as well as γδ TCR lymphocytes,were greatly reduced by FTY720 therapy.The similar action of FTY720 was also revealed in Gr1+CD11b+ monocytes.CONCLUSION：FTY720 is efficient on alleviating allo-immune response by reducing the infiltration of both lymphocytes and monocytes into the graft in a mouse intestinal transplantation model.