中文摘要：

目的：研究喜树碱（CPT）对刀豆蛋白A（ConA）介导的小鼠T淋巴细胞体外活化、增殖及细胞周期的影响。方法：以ConA刺激小鼠T淋巴细胞，建立小鼠T淋巴细胞活化、增殖的模型，以不同浓度的CPT作用于该模型，流式细胞术检测T细胞早期活化标志CD69分子的表达；以活体染料羧基荧光素乙酰乙酸（CFDA-SE）染色流式细胞术分析CPT在ConA刺激下小鼠淋巴细胞的增殖相关指数（PI）；以碘化丙啶染色流式细胞术分析细胞周期的分布情况。结果：ConA作用6h后流式细胞术分析显示CD69的表达率为（58．88±0．55）％，不同浓度的CPT组（10nmoL／L、20nmol／L、50nmol／L、100nmol／L）CD69的表达率分别为（55．48±0．98）％、（54．67±1．05）％、（50．40±0．82）％、（42．47±1．32）％，均可明显抑制CD69的表达（P〈O．01）；ConA刺激48h后流式细胞术分析显示，不同浓度的CPT组（10nmol／L、20nmol／L、50nmol／L、100nmol／L）的增殖指数（PI）明显低于对照组（P〈0．05）；细胞周期分析显示刺激48h后不同浓度的CPT组（10nmol／L、20nmol／L、50nmol／L、100nmol／L）均出现明显的凋亡峰（apoptosis peak，AP），sub-G1期、G0／G1期细胞的比率明显高于ConA刺激组（P〈0．01）。结论：CPT可明显抑制ConA刺激的T淋巴细胞的活化、增殖，同时使淋巴细胞阻滞于G0／G1期。

英文摘要：

AIM： To study the effects of camptothecin （CPT） on the activation, proliferation and cell - cycle distribution of the mouse T lymphocytes stimulated by concanvalin A （ConA） in vitro. METHODS： A model of T cell activation and proliferation was established by stimulated the cells with Con A. T cells were treated with different concentrations of CPT. The expression of CD69, the early marker of CD3^＋ T cell activation, was measured by FACS. The proliferation index was determined by carboxyl fluorescin diacetate succinmidyl ester by flow cytometry. The cell - cycle distribution was analyzed by propidium iodide staining. RESULTS： After stimulation with Con A for 6 h, the activation rate of CD69^＋ T cell in Con A group was （58. 88±0. 55 ） %. The percentages of CD69 positive cells were （55.48±0. 98 ） %, （54. 67±1.05） %, （50. 40±0. 82） %, （42.47±1.32） %, correspond to the treatments with different concentrations of CPT （ 10 nmol/L, 20 nmol/L, 50 nmol/L, 100 nmol/L）, respectively. After 48 h treatment with Con A, the proliferation index in different concentrations of CPT treatment （ 10 nmol/L, 20 nmol/L, 50 nmol/L and 100 nmol/L） exerted a definite inhibitory effect on the proliferation （ P 〈0. 01 ）. Moreover, the cell-cycle distribution analysis showed that apoptosis peak was observed in different concentrations of CPT treatment after 48 h cultured with Con A. CONCLUSION： CPT significantly inhibits the early stages of the Con A-induced T cell activation and proliferation, and detents the T lymphocytes in G0/G1 phase.