老年人外周血淋巴细胞CD28及CD95表达变化研究

Change of the expression of CD28 and CD95 on peripheral blood lymphocytes in the elderly

目的通过对老年人与成年人外周血淋巴细胞CD28及CD95表达水平的比较性研究，观察淋巴细胞凋亡在免疫衰老中的作用。方法采用免疫荧光标记流式细胞术，分析成年组（20-59岁）与老年组（60-90岁）各20例的外周血淋巴细胞表型水平。结果老年组CD28^＋CD95^-[（8.80±4、86）％]及CD28^＋细胞[（36．32±10．38）％]明显低于成年组[（23.09±3．48）％、（52．29±4、90）％]（P〈0.01），而CD28^-CD95^＋[（53．23±8．28）％]、CD95^＋[（80．25±7、19）％]及CD28^-细胞[（63．68±10、38）％]明显高于成年组[（33．58±4．72）％、（63．18±4．12）％、（47.71±4．90）％]（P〈0．01）。结论老年人CD28^＋表达随年龄增长而下降。CD28^-及CD95^＋表达随年龄增长而上升。提示淋巴细胞凋亡在免疫衰老中可能具有重要作用。

Objective To observe the change of the cell immune function with aging by detecting the expression of CD28 and CD95 on peripheral blood lymphocytes. Methods The fluorescent flow cytometry was used to analyze the expression of peripheral blood lymphocyte phenotype of the adult and elderly groups, Results CD28^＋ CD95^- , CD28^＋ cells of the peripheral blood lymphocyte in the elderly group（ 8, 80±4.86% , 36.31±10. 38% ） were significantly lower than those in the adult group（23.09±3.48% ,52.29±4. 90% ） （P 〈 0. 01 ）, CD28^- CD95^＋ , CD95^＋ and CD28^- cells in the elderly group（53.23±8.28% ,80.25±7.19% ,63.68±10. 38% ） were significantly higher than those in the adult group（33.58±4. 72% ,63.18±4.12% ,47. 71±4.90% ） （P 〈0.01 ）, Conclusions The decreased CD28^＋ expression and the increased CD28^- and CD95^＋ expression with aging suggest that lymphocyte apoptosis may play an important role in the immunosenescence.