槲皮素对小鼠T细胞体外活化的抑制作用

目的:通过分析槲皮素对淋巴细胞早期活化标记物CD69表达的影响,探讨其对T淋巴细胞体外活化抑制作用的机制。方法:分离小鼠淋巴结细胞,加入多克隆刺激剂及槲皮素共同培养,分别于2、6、24h收获细胞,进行双色免疫荧光标记,以流式细胞仪对T细胞的CD69分子表达情况进行分析并计算抑制率。结果:槲皮素(终浓度10μmol/L)对未受刺激的T细胞CD69表达百分率无明显影响,而经佛波醇酯(PDB)及刀豆蛋白A(ConA)活化同时加入槲皮素的T细胞CD69表达百分率在2h、6h及24h均显著下降(P＜0.01)。槲皮素对PDB的抑制率随作用时间延长而明显下降,对ConA的抑制率平缓而持久。结论:槲皮素对PDB、ConA活化的T淋巴细胞均显示明显的抑制效应,表明该药可能作用于T细胞活化信号传递通路蛋白激酶Cθ或其下游部位,并且,这种抑制效应表现出一定的可逆性。

The inhibitory effect of quercetin on in vitro activation of T lymphocytes

AIM:To investigate the inhibitory effect of quercetin on in vitro activation of T lymphocytes by polyclonal activators with CD69 expression as an activation marker.METHODS:After being separated from lymphoid nodes of a C57BL/6 mouse, the lymphocytes were exposed to polyclonal activators (PDB or Con A) with or without quercetin. Then they were harvested at 2 h, 6 h and 24 h, respectively. The expressional rates of CD69 on T lymphocytes were assessed by two-color immunofluorescent staining and flow cytometry, and the inhibitory rates of quercetin at different time points were estimated.RESULTS:Quercetin had no effect on the expressional rate of CD69 on T lymphocytes under resting states. After the stimulation with PDB or Con A, the expressional rates of CD69 on T lymphocytes in the present of quercetin (10 μmol/L) showed significant decrease compared with those of control groups at different time points (P＜0.01). The inhibitory rate of quercetin on CD69 expression stimulated by PDB dropped sharply from 2 h to 24 h, whereas the inhibitory rate of quercetin on Con A action were relatively stable.CONCLUSION:Quercetin has inhibitory effects on the activation of T lymphocytes by Con A or PDB, suggesting that the action site of quercetin may be on PKCθ or its downstream. Furthermore,these inhibitory effect seems to be reversible.