受体淋巴细胞向小肠移植物相关淋巴组织迁移的实验研究

目的：动态分析移植小肠各淋巴组织内供、受体淋巴细胞的表型及免疫状态，以推断其在小肠移植排斥反应中的作用。 方法： 小鼠小肠移植后2、4、6 d，观测移植物排斥病理形态变化，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）中淋巴细胞中供、受体淋巴细胞的比例及激活状态。 结果:在移植后6 d，组织学观测到移植物开始出现排斥征象；移植后2、4 d，移植肠MLN、PP内受体来源的淋巴细胞迅速取代供体细胞，而移植肠IEL与LPL内受体来源的淋巴细胞比例增加速度略慢，但在移植后6 d也基本取代供体细胞；在移植后4 d，受体来源的T细胞表达激活分子CD69与CD25的比例达到89.8%±3.4％和84.5%±10.2％，显著高于供体T细胞与受体自身肠道中的T细胞。 结论:移植小肠内的淋巴组织在移植后早期即被受体来源的淋巴细胞迅速取代并激活，抑制这一过程可应用于缓解排斥反应。

Rapid migration of host lymphocytes into the lymphoid tissue of the intestinal graft at early stage after transplantation

AIM:To determine the migration mode of host lymphocytes into the intestinal graft by analyzing different lymphoid compartments of the graft. METHODS:2, 4, 6 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 for analyzing by cytometry. RESULTS:At the day 2 and day 4, no evidence of rejection in intestinal allograft was found, while the rejection signs were apparent at the 6th day. At day 2 and day 4, host lymphocytes had rapidly replaced donor cell in graft MLN and PP. The migration of host lymphocytes into the LPL and IEL was not as fast as MLN and PP, however, the near-total replacement took place at the 6th post transplant day. The host lymphocytes were activated at the early stage of recruitment into the graft. CONCLUSION:The rapid recruitment of recipient lymphocytes and early activation could be responsible for the formidable rejection of intestinal transplantation.