胸腺切除对小鼠胸腺功能及外周T淋巴细胞的影响

Effects of surgical thymectomy on thymic function and peripheral T cell populations in mice

目的通过小鼠模型研究胸腺切除对免疫学功能的影响。方法将新生期及幼龄期BALB/c小鼠分别随机分为2组,每组20只:行开胸手术并切除胸腺为手术组;除不切除胸腺外其余操作同前为假手术组。然后将2组再分别随机分为2个亚组,每组10只:一组于术后1个月,另一组于术后2个月,分别通过实时定量PCR检测T细胞受体重排删除环(TREC)、流式细胞术检测外周血T淋巴细胞及其亚群评估胸腺功能及外周血T淋巴细胞的变化。结果手术组外周血T淋巴细胞总数及其亚群、TREC明显低于假手术组,差异有统计学意义(P<0.01)。新生期与幼龄期比较以及术后1月与术后2月检测指标比较,差异无统计学意义(P>0.05)。结论幼年个体在开胸手术中切除胸腺会造成术后T细胞免疫功能降低,其影响可能与手术时年龄无关,且长期存在。

Objective To investigate the effect of surgical thymectomy on immune function and peripheral blood T lymphocytes of a mouse model. Methods Neonatal（ aged 72 hours） and infant（ aged 1 week） BALB /c mice were randomly divided into two groups with 20 mice in each group,respectively. The mice of surgical group underwent a surgical thymectomy; the sham operation group excluded the thymectomy procedure. Then surgical group and sham operation group were randomly divided into two subgroups with 10 mice in each group,respectively. One subgroup was sacrificed one month after operation; the other was sacrificed two months after operation. To evaluate thymic function and peripheral T cell populations,T cell receptor rearrangement excision circles（ TREC） were assessed by real-time quantitative PCR and T lymphocyte and its subset were detected by flow cytometry. Results The levels of peripheral T cell populations and TREC of the operation group were significantly lower than those of the sham operation group（ P〈 0. 01）. There were no significant differences in the measurements between neonatal and infant mice or between one month after operation and two months after operation（ P〉 0. 05）. Conclusion Thymectomy in young mice can make damage on T cell immune system. The damage may continue in a long term and the age of operation maybe don＇t have an effect on it.