脐血移植发生移植物抗宿主病与T细胞表达CD94的关系

Correlation of graft versus host disease to CD94 molecule on T lymphocytes following umbilical cord blood transplantation

背景:据作者检索脐血移植中有关T细胞表达CD94与移植后发生急/慢性移植物抗宿主病的关系尚无报道。目的:初步探讨T细胞表达CD94在脐血移植免疫耐受中的作用。设计:病例-对照分析。对象:1999-01/2007-06中山大学附属第二医院造血干细胞移植中心行脐血移植的14例患儿,年龄2~9岁,中位年龄6.8岁;接受HLA全相合血缘相关脐血移植患儿9例,接受无关供者脐血移植5例。同时选取体检正常的34例儿童外周血标本作为对照,由中山大学附属二院儿科提供,男18例,女15例,平均年龄4.5岁。方法:抽取正常儿童外周静脉血2mL,14例患儿均在脐血移植后造血恢复至中性粒细胞绝对数≥0.5×109L-1时开始采集外周静脉血2mL,血液样本均置于EDTA-2Na抗凝管,待测细胞表面抗原。每1~3个月检测1次,至随访结束。所有样本在6h内完成标定,均采用双色和三色直接免疫荧光标记法,流式细胞仪检测外周血T细胞表面CD94的表达。主要观察指标:脐血移植后移植物抗宿主病的发生。移植物抗宿主病与外周血T细胞表面CD94表达的关系。结果:9例接受同胞脐血移植的患儿中,有6例未发生急性移植物抗宿主病,其余3例及接受非血缘相关脐血移植的5例患儿均于移植后6d^50d发生急性移植物抗宿主病,5例患儿发生慢性移植物抗宿主病。与正常对照比较,全部脐血移植患儿CD3+CD4+CD94+T细胞、CD3+CD8+CD94+T细胞的表达均明显升高(P<0.05)。与未发生急性移植物抗宿主病患儿比较,急/慢性移植物抗宿主病患儿CD3+CD4+CD94+T细胞、CD3+CD8+CD94+T细胞的表达均明显升高(P<0.05)。结论:脐血移植后发生急/慢性移植物抗宿主病时T细胞高表达CD94,提示T细胞CD94分子的活化参与了移植物抗宿主病的发生。

AIM： There are no studies on the correlation of T cells expressing CD94 to acute/chronic graft versus host disease after umbilical cord blood transplantation. OBJECTIVE： To determinate the effect of CD94 molecule on T lymphocyte in immune tolerance after umbilical cord blood transplantation. DESIGN： Case-control analysis. PARTICIPANTS： Fourteen children aged 2-9 years, averagely 6.8 years, undergoing umbilical cord blood transplantation were enrolled at the Center of Hematopoietic Stem Cell Transplantation, Second Affiliated Hospital, Sun Yat-sen University from January 1999 to June 2007. Nine children received HLA compatible transplantation, and five received unrelated donor transplantation. Simultaneously, peripheral blood samples of 34 children, who were normal after body examination, were used as controls, which were obtained from the Department of Pediatrics, Second Affiliated Hospital, Sun Yat-sen University, including 18 males and 15 females, averagely 4.5 years in age. METHODS： 2 mL of peripheral vein blood was collected from each normal child. 2 mL of peripheral vein blood was collected from each child patient following their absolute number of neutrophilic granulocytes was ≥0.5×10^9 L^-1 after umbilical cord blood transplantation. Blood samples were placed in EDTA-2Na anticoagulation tube for measuring cell surface antigen, The measurement was performed once every 1-3 month until the end of the follow-up. All samples were subjected to standardization within 6 hours using double color and three color immunofluorescent staining. Flow cytometry was used to detect the CD94 expression on the T cell surface in the peripheral blood. MAIN OUTCOME MEASURES： Occurrence of graft versus host disease following umbilical cord blood transplantation; Correlation of graft versus host disease to CD94 expression on the T cell surface in the peripheral blood, RESULTS： Six cases undergoing compatible related umbilical cord blood transplantation had no acute graft versus host disease, but others developed acute graft versus host disease at 6-50 days after transplantation, Five cases developed chronic graft versus host disease. Compared with the normal controls, expression of CD3＋CD4＋CD94＋ T cells and CD3＋CD8＋CD94＋T cells significantly increased （P 〈 0.05）. Compared with patients who did not develop acute graft versus host disease, the expression of CD3＋CD4＋CD94＋ T cells and CD3＋CD8＋CD94＋ T cells in patients with acute/chronic graft versus host disease significantly increased （P 〈 0.05）. CONCLUSION： The patients after umbilical cord blood transplantation with acute graft versus host disease expressed CD94 on T lymphocytes in a high level, which suggested that the activation of CD94 molecule on T lymphocyte takes part in the development of graft versus host disease.