小鼠脾脏和外周血免疫细胞及部分细胞因子的增龄性变化

Age-related changes of immune cells and some cytokines in spleen and peripheral blood of mice

目的探索不同年龄小鼠脾脏和外周血免疫细胞、细胞因子的变化。方法24只雄性C57BL/6J小鼠分为幼年(1月龄)组7只、青年(2月龄)组7只、中年(12月龄)组7只、老年(17月龄)组3只。分别用流式细胞术和ELISA检测小鼠脾脏和外周血免疫细胞(CD3^(-)CD19^(+)B细胞、CD3^(+)CD4^(+)T细胞、CD3^(+)CD8^(+)T细胞、CD3^(-)CD49b^(+)NK细胞、CD11b-CD11c^(+)DC细胞、CD11b^(+)Ly6C^(med) Ly6G^(+)粒细胞、CD11b^(+)Ly6C^(hi) Ly6G^(-)单核细胞)的比例和细胞因子(IL-1β、IL-6、IFN-γ)的水平。结果中年组小鼠脾脏CD3^(-)CD19^(+)B细胞比例比幼年组、青年组显著降低(P<0.05),同样,老年组小鼠脾脏CD3^(-)CD19^(+)B细胞比例比幼年组、青年组显著降低(P<0.05);青年组小鼠脾脏CD3^(+)CD4^(+)T细胞比例比幼年组小鼠升高(P<0.01);中年组小鼠脾脏CD11b^(+)Ly6C^(hi) Ly6G^(-)单核细胞比例比幼年组、青年组小鼠明显升高(P<0.05)。外周血中,中年组小鼠CD3^(+)CD4^(+)T细胞比例比幼年组、青年组小鼠降低(P<0.05),同样,老年组小鼠CD3^(+)CD4^(+)T细胞比例比幼年组、青年组小鼠降低(P<0.05);中年组小鼠外周血CD3^(+)CD8^(+)T细胞比例比幼年组、青年组小鼠明显升高(P<0.05);中年组小鼠外周血CD11b^(+)Ly6C^(hi) Ly6G^(-)单核细胞比例比幼年组、青年组小鼠显著升高(P<0.01),老年组小鼠外周血CD11b^(+)Ly6C^(hi) Ly6G^(-)单核细胞比例比幼年组、青年组小鼠显著升高(P<0.01)。中年组、老年组小鼠脾脏IL-1β水平比青年组小鼠明显降低(P<0.05)。而中年组小鼠血清IL-6水平比幼年组、青年组鼠显著升高(P<0.01),同样,老年组小鼠血清IL-6水平均比幼年组、青年组鼠显著升高(P<0.05)。其余免疫细胞与细胞因子随月龄增长差异无统计学意义。结论随着月龄增长,脾脏中CD3^(-)CD19^(+)B细胞比例、IL-1β水平逐渐降低,外周血中CD3^(+)CD4^(+)T细胞比例逐渐降低、CD11b^(+)Ly6C^(hi) Ly6G^(-)单核细胞比例IL-6水平也逐渐升高,可能与不同月龄机体免疫状态相关。

Objective To explore the dynamic changes of immune cells and cytokines in the spleen and peripheral blood of mice at different ages.Methods Twenty-four male C57BL/6 mice were divided into four groups:childhood group(one month old,n=7),youth group(two months old,n=7),middle-age group(12 months old,n=7)and aged group(17 months old,n=3).The proportions of CD3^(-)CD19^(+)B cells,CD3^(+)CD4^(+)T cells,CD3^(+)CD8^(+)T cells,CD3^(-)CD49b^(+)natural killer(NK)cells,CD11b-CD11c^(+)dendritic cells(DC),CD11b^(+)Ly6C^(med) Ly6G^(+)granulocytes and CD11b^(+)Ly6C^(hi) Ly6G^(-)monocytes in spleen and peripheral blood of mice were detected by flow cytometry.The levels of interleukin-1β(IL-1β),interleukin-6(IL-6),and interferon-γ(IFN-γ)in spleen and peripheral blood of mice were detected by enzyme-linked immunosorbent assay.Results The proportion of CD3^(-)CD19^(+)B cells in spleen in middle-age group and aged group was significantly lower than that in childhood group and youth group(P<0.05).The proportion of CD3^(+)CD4^(+)T cells in spleen in youth group was higher than that in childhood group(P<0.01),and the proportion of CD11b^(+)Ly6C^(hi) Ly6G^(-)monocytes in spleen in middle-age group was significantly higher than that in childhood group and youth group(P<0.05).In peripheral blood,the proportion of CD3^(+)CD4^(+)T cells in middle-age group and aged group was lower than that in childhood group and youth group(P<0.05).The proportion of CD3^(+)CD8^(+)T cells in peripheral blood in middle-age group was significantly higher than that inchildhood group and youth group(P<0.05).The proportion of CD11b^(+)Ly6C^(hi) Ly6G^(-)monocytes in peripheral blood of mice in middle-age group was significantly higher than that in childhood group and youth group(P<0.01).The proportion of CD11b^(+)Ly6C^(hi) Ly6G^(-)monocytes in peripheral blood in aged group mice was significantly higher than that in childhood group and youth group(P<0.01).The level of IL-1βin spleen in middle-age group and aged group was significantly lower than that in youth group(P<0.05).The serum level of IL-6 in middle-age group was significantly higher than that in childhood group and youth group(P<0.01),and it was also significantly higher in aged group than in childhood group and youth group(P<0.05).There was no significant difference in the other immune cells and cytokines between four groups.Conclusion With the increase of age,the proportion of CD3^(-)CD19^(+)B cells and the level of IL-1βin spleen decrease gradually,the proportion of CD3^(+)CD4^(+)T cells decreases gradually in peripheral blood,while the proportion of CD11b^(+)Ly6C^(hi) Ly6G^(-)monocytes and the level of IL-6 increase gradually,which may be related to the immune status of different months of age.