可溶性CD40配体对人B细胞淋巴瘤细胞系BJAB增殖、凋亡的影响及其机制

Effects of soluble CD40 ligand on proliferation and apoptosis of Human B cell lymphoma cell line BJAB and its mechanism

目的观察可溶性CD40配体(s CD40L)对人B细胞淋巴瘤细胞系BJAB增殖、凋亡的影响,并探讨其机制。方法培养BJAB细胞并将其分为实验组、阳性对照组、空白对照组。实验组分别加入0、1、2、3、4、5、6、7g/m L的s CD40L,空白对照组加入同量生理盐水,阳性对照组加入10 mol/L的地塞米松。用不同浓度为的s CD40L作用于BJAB细胞,在24、48、72 h用MTT法测算细胞增殖抑制率;应用流式细胞术观察凋亡细胞及不同周期细胞;采用Western blotting法检测细胞中的Bax、Bcl-2、Caspase-3蛋白。结果阳性对照组及实验组不同浓度s CD40L处理的细胞培养48、72 h后增殖抑制率高于培养24 h时(P均<0.05)。随着s CD40L作用浓度升高,实验组BJAB细胞增殖抑制率升高。实验组、阳性对照组G_1期细胞百分比增高,S期细胞百分比下降;实验组中,6 g/m L亚组G_1期细胞百分比高于2、4 g/m L亚组,S期细胞百分比低于2、4 g/m L亚组(P均<0.05)。实验组、阳性对照组细胞凋亡率高于空白对照组(P均<0.05);实验组中6 g/m L亚组细胞凋亡率低于阳性对照组(P<0.05)。实验组及阳性对照组细胞中Bax、Caspase-3蛋白相对表达量高于空白对照组,Bcl-2蛋白相对表达量低于空白对照组(P均<0.05)。结论 s CD40L可抑制BJAB细胞增殖、诱导其凋亡,机制可能与上调Bax、Caspase-3蛋白表达及下调Bcl-2蛋白表达和干扰细胞周期有关。

Objective To observe the effects of soluble CD40 ligand（ s CD40L） on cell proliferation and apoptosis of human lymphoma BJAB cell line and to investigate its mechanism. Methods BJAB cells were cultured and then were divided into the experimental group,positive control group and blank control group. The 1,2,3,4,5,6 and 7 g / m L s CD40 L were separately added to the experimental group,the same amount of normal saline was added to the blank control group,and 10 mol / L dexamethasone was added to the positive control group. Different concentrations of s CD40 L were applied to BJAB cells at 24,48 and 72 h. MTT assay and flow cytometry（ FCM） were used to detect the inhibition rate,apoptosis and cell cycle distribution,respectively. Western blotting was used to detect the expression of Bax,Bcl-2 and Caspase-3. Results The proliferation inhibition rates of the positive control group and experimental group treated with different concentrations of s CD40 L after 48 and 72 h was higher than that after 24 h（ P〈0. 05）. With the increase of s CD40 L concentration,the proliferation inhibition rate of BJAB cells was increased in the experimental group. The cell percentage of G_1 phase increased both of the experimental group and positive control group,and the cell percentage of S phase decreased. In the experimental group,the cell percentage of G_1 phase in 6 g / m L subgroup was higher than that of 2,4g / m L subgroups,and the cell percentage of S phase was lower than that of 2,4 g / m L subgroups（ all P〈0. 05）. The apoptosis rates of the experimental group and positive control group were higher than that of the control group（ all P〈0. 05）.In the experimental group,the apoptosis rate of 6 g / m L subgroup was lower than that of the positive control group（ P〈0. 05）. The relative expression of Caspase-3 and Bax protein in the experimental group and positive control group was higher than that in the blank control group,and the relative expression of Bcl-2 protein was lower than that of the control group（ all P〈0. 05）. Conclusions s CD40 L can inhibit cell proliferation and induce apoptosis in BJAB cells,and the mechanism may be related to up-regulation of Bax,Caspase-3 protein expression,down-regulation of Bcl-2 protein expression and interfering with the cell cycle.