各年龄段小鼠胸腺TEC中IL-7表达的变化

The expression of IL-7 on the age-related thymic involution in mice

目的探讨IL-7在小鼠胸腺增龄性萎缩中的作用。方法 SPF级C57BL/6小鼠分成老龄组(18月)、中龄组(12月)、中青龄组(6月)、青龄组(1月),每组雌雄各6只。无菌取胸腺,比较小鼠胸腺重量、胸腺指数及胸腺细胞数;应用RTPCR技术检测胸腺组织中IL-7基因的表达。结果小鼠胸腺重量及胸腺细胞数随年龄增长显著减少;C57BL/6小鼠胸腺IL-7相对表达量分别为:(1.052±0.137)、(0.578±0.040)、(0.441±0.171)、(0.184±0.139),表现为随年龄增长显著下调,各年龄组间存在显著差异。结论 IL-7参与了胸腺的形成、发育、成熟和退化萎缩各个阶段,其表达水平在TECs不同的发育时期呈现不同的特点,IL-7对胸腺维持和萎缩衰老具有显著影响,IL-7表达随着年龄的增长呈显著减少,从而影响到TECs分化和增殖,造成胸腺微环境恶化引起胸腺萎缩。

Objective To investigate role of IL-7 on the age-related thymic involution in mouse. Methods SPF grade C57BL/6 mice were divided into older age（ 18 months ） , middle-aged （ 12 months ） , younger age （ 6 and 4 months ） , young age groups （ 1 months ） , 6 male and 6 female of each group. Sterile thymus compare mouse thymus weight, thymus index and the number of thymocytes were compared and the IL-7 gene expression in thymus tissue was detected by real-time PCR. Results The thymus weight and thymocyte were significantly reduced along with the age growth;the relative expression of IL-7 in the thymus of C57BL,/6 mice were 1-month-old 1. 052 ：t： 0. 137, 6-month-old 0. 578 ± 0. 040, 12-month-old 0. 441 ± 0. 171, 18-month-old 0. 184 ± O. 139, and there were significant differences among the four groups. Conclusions IL-7 involves in the formation of the thymus, the development, maturation and degradation in various stages, the ex-pression levels of IL-7 in the different developmental period present different characteristics.