目的　研究老年人淋巴细胞亚群及其细胞凋亡过程 ,探讨中药成分PE对细胞凋亡的调控作用。方法　用间接免疫荧光技术检测淋巴细胞表型 ,用MTT法测定淋巴细胞增殖应答 ;用流式细胞仪及自动图象分析来检测细胞凋亡。结果　老年人淋巴细胞比青年人淋巴细胞的增殖应答能力低 ,CD4 5RA+细胞亚群减少 ,而CD4 5RO+细胞亚群增多 ,后者易发生凋亡。而中药成分PE对老年人淋巴细胞凋亡有抑制作用。结论　老年人淋巴细胞易于细胞凋亡 ,取决于活化 ,称为活化诱导性细胞死亡 ,此在免疫衰老中起着重要作用。研究结果启示可从中药开发细胞凋亡的调节药物 Objective To study the lymphocyte subsets and its apoptosis process in the elderly and to explore the regulation effect of PE, a component of traditional Chinese medicine, on apoptosis. Methods The in vitro immunofluorescence technique was used to detect the phenotype of lymphocytes. The lymphocyte proliferation response was measured by MTT assay. Apoptosis was detected by flow cytometry and automated image analysis. Results The lymphocyte proliferative response capacity of lymphocytes in the elderly was lower than that in young people, and CD4 5RA+ cell subsets decreased, while CD4 5RO+ cell subsets increased, and the latter prone to apoptosis. The traditional Chinese medicine ingredient PE has inhibitory effects on lymphocyte apoptosis in the elderly. Conclusion Lymphocytes in the elderly are prone to apoptosis, which is dependent on activation and is called activation-induced cell death. This plays an important role in immune aging. The results of the study suggest that regulatory drugs that can develop apoptosis from TCM can be developed