γ射线对小鼠造血功能及T细胞亚群功能的影响  

The effects of γ-ray radiation on hematopoiesis and T lymphocyte subset function

作　　者：韩文秀[1] 郑智茵[2] 尹利明[1] 高瑞兰[1] 

机构地区：[1]浙江中医药大学第一临床医学院,杭州310006 [2]浙江省中医院血液科

出　　处：《中华放射医学与防护杂志》2014年第3期172-175,187,共5页Chinese Journal of Radiological Medicine and Protection

基　　金：浙江省科技计划项目（2010C33098）;浙江省中管局项目（2010ZB035）

摘　　要：目的 观察γ射线对小鼠造血功能及外周血T细胞相关细胞因子和脾脏T细胞转录因子的影响,探讨射线引起的造血功能损伤与免疫异常的相关性.方法 将50只BALB/e小鼠用随机数字表法分为两组：照射组（40只）和空白对照组（10只）,照射组小鼠予60Coγ射线（1.0 Gy/min,5.5 min）照射,空白对照组予假照射,照射组于照射后4、8、12及20 d,空白对照组于20 d,计数小鼠外周血白细胞和血小板;骨髓病理切片观察骨髓造血组织增生情况;流式细胞微球芯片捕获技术（CBA）检测外周血中Th 1/Th2/Th 17细胞因子含量变化;Western blot法检测脾脏Th1/Th2、Th17/Treg细胞分化特异性转录因子T-bet/GATA-3、RORγt/Foxp3蛋白表达水平.结果 照射组小鼠外周血白细胞和血小板计数较空白对照组显著降低（t白细胞=18.48、15.72、9.79、3.30,t血小板=22.52、19.74、11.78、4.70,P＜0.05）.照射组骨髓病理切片与空白对照组相比,骨髓增生显著低下,造血组织面积减少,被脂肪组织大量替代,巨核细胞少见,照射后8d较20 d骨髓抑制更明显.照后8和12d,照射组小鼠外周血Th1类细胞因子IFN-γ、TNF-α及Th2类细胞因子IL-4、IL-6含量较空白对照组明显升高,IL-17A含量照射组较空白对照组亦明显升高（tIFN-γ=2.93、3.36,tTNF-α=6.09、8.11、6.43、4.49,tIL-4=4.49、3.18,tIL-6=5.11、8.67、6.67、8.55,P＜0.05）.与空白对照组比较,照射组脾脏RORγt蛋白在照射后4、8和12d及GATA-3、Foxp3蛋白在各时间点表达水平均降低（tRORγt=6.79、4.31、4.47,tGATA-3=3.88、8.06、2.84,3.23,tFoxp3=10.00、8.06、2.89、5.93,P＜0.05）.而照射组T-bet蛋白表达较空白对照组升高（t=5.64、2.75、3.56、4.65,P＜0.05）.结论 5.5 Gyγ射线照射后引起小鼠骨髓造血抑制,同时导致Th 1/Th2、Th17/Treg细胞亚群功能失衡,提示由射线引起的免疫异常可能参与骨髓造血功能的损伤.Objective To observe the effects of whole body ^-ray radiation on hematopoiesis and cytokines related to T cell subsets in mouse, to detect the expression of transcription factors of splenic T cell subsets, and to investigate the correlation between hematopoiesis injury and abnormal immune function. Methods Totally 50 BALB/c mice were divided into radiation group and blank control group with the random number table method. The former group were given 5.5 Gy 60Co γ-ray radiation on whole body and another received sham radiation. The numbers of white blood cells and platelets of radiation group were counted at 4, 8, 12 and 20 d after radiation, and these numbers of blank control mice were counted only at 20 d. Hematopoietic tissue proliferation was evaluated by biopsy sections of mice femur. The contents of Thl, Th2, and Thl7 in peripheral blood were detected with eytometrie bead array （CBA）. The expressions of T-bet/GATA-3 and RORγt/Foxp3 proteins related to the differentiation of T cell subsets in spleen tissue were measured by Western blot. Results The numbers of white blood cells and platelets of radiation group mice were reduced obviously （t wsc = 18.48, 15.72, 9.79, 3.30; t PLT = 22.52, 19.74, 11.78, 4. 70, P 〈 0.05） compared with blank control group. Biopsy sections showed that bone marrow hematopoietic cells of the radiated mice were less than those of blank group, and adipocytes became more. At 8 d, the marrow suppressions were more obvious than those at 20 d. Serum contents of Thl cytokines IFN-/, TNF-c~ and Th2 cytokines IL-4, IL-6 in the radiation group were higher than those in the blank control group at8 and 12 d（ t IFN-y =2.93, 3.36, t rNr-~ =6.09, 8. 11, 6.43, 4.49, tiL.~ =4.49, 3. 18, t IL~ = 5. 11, 8. 67, 6. 67, 8. 55, P 〈 0.05）. IL-17A secreted mainly by Thl7 cells was also higher than the blank （t = 3.68, 6.24, 5.32, 4.06, P 〈 0. 05 ）. Compared with the blank control group, the expression of T-bet protein increased significantly （ t = 5.64, 2.75, 3.56, 4.65, P 〈 0. 05

关 键 词：Γ射线 T细胞亚群 细胞因子 转录因子 

分 类 号：R818[医药卫生—放射医学]