正常人外周血淋巴细胞凋亡受体的表达与细胞凋亡的关系

本研究检测凋亡受体Fas、TNFRⅠ、TNFRⅡ在人外周血淋巴细胞（PBL）增殖过程中的表达情况及其细胞周期特异性,并探讨其与凋亡受体途径介导的细胞周期特异性细胞凋亡的关联性。应用双参数流式细胞术检测人外周血淋巴细胞在G0期和经植物凝集素刺激（PHA）进入细胞周期后Fas、TNFRⅠ、TNFRⅡ的表达情况以及细胞周期特异性,同时检测肿瘤坏死因子-α、抗Fas抗体诱导人外周血淋巴细胞的凋亡。结果表明：经植物凝集素刺激24小时后的外周血淋巴细胞Fas、TNFRⅠ、TNFRⅡ表达率较G0期外周血淋巴细胞分别增加了（35.55±6.63）%,（30.63±2.66）%,（26.62±5.14）%,均具有显著性差异（P〈0.01）,而且主要表达在G1期;未经植物凝集素刺激的外周血淋巴细胞停留在G0期,TNF-α和anti-Fas诱导后没有发生凋亡,而刺激后进入细胞周期的淋巴细胞经TNF-α和anti-Fas诱导后发生凋亡,其凋亡主要在G1期。结论：凋亡受体在外周血淋巴细胞中的表达与凋亡受体途径介导的细胞凋亡有明显的量效关系,凋亡受体途径介导细胞凋亡的细胞周期特异性与凋亡受体表达的细胞周期特异性有关,细胞凋亡的发生与细胞是否进入细胞周期有关。

Relationship of Apoptotic Receptor Expression in Normal Human Peripheral Blood Lymphocytes to Cell Apoptosis

The aim of this study was to detect the expression and cell cycle specificity of Fas, TNFRI and TNFRII in human peripheral blood lymphocytes (PBL), and to study the potential role of Fas, TNFRIand TNFRII in cell cycle specific apoptosis. The improved double-parameter flow cytometry was used to detect the expressions of Fas, TNFRI and TNFRII and cell cycle specificity in PBL which were incubated for 24 hours in the presence or absence of phytohaematoagglutinin (PHA) respectively. Apoptosis induced by IgM type anti-Fas and TNF-alpha was detected by API method. The results showed that compared with PBL treated in the absence of PHA in G(0) phase, the ratio of Fas, TNFRI and TNFRII expressions in PHA-stimulated PBL entering cell cycle increased (35.55 +/- 6.63)%, (30.63 +/- 2.66)%, (26.62 +/- 5.14)% respectively (P < 0.01), and mainly appeared at G(1)-phase; no apoptosis was induced by anti-Fas and TNF-alpha in G(0)-phase PBL cultured in the absence of PHA. On the contrary, the apoptosis was induced by anti-Fas and TNF-alpha in PBL which entered cell cycle after stimulation with PHA and mainly initiated at G(1)-Phase. It is concluded that there is evident dose-effect relationship between apoptotic receptor and receptor-mediated apoptosis. Moreover, the cell cycle specificity of receptor-mediated apoptosis is correlated with the cell cycle specific expressions of apoptotic receptor. The induction of apoptosis by apoptotic factors (anti-Fas and TNF-alpha) depends on whether cell entering cell cycle or not.