再生障碍性贫血模型小鼠骨髓造血细胞CD95和Bcl-2的表达

Expressions of CD95 and Bcl-2 in bone marrow haemopoietic cells from mice with aplastic anemia

目的探讨再生障碍性贫血模型小鼠骨髓造血细胞凋亡过程中CD95和Bcl-2的表达以及相互之间的关系。方法用辐射和免疫介导的方法制造小鼠的再生障碍性贫血模型。用流式细胞术分析模型组和正常对照组CD34＋细胞和CD45^＋细胞，以及细胞表面CD95和胞内Bcl-2的表达。结果模型组骨髓细胞中低表达CD45的CD34＋细胞（CD34^＋CD45^＋low细胞）比例低于对照组[（0．85±0．19）％比（1．21±O．28）％，P〈0．05]。有核细胞中，CD95在模型组中的表达比例明显高于对照组[（66．30±7．68）％比（42．78±15．12）％]，在这2组CD34±CD45±细胞的表达分别为（69．21±9．36）％和（22．31±3．33）％，CD34^＋CD45low细胞的表达分别为（53．70±16．46）％和（7．68±4．42）％，均P〈0．01。Bcl-2的表达比例仅在模型组CD34±CD45low细胞中增加，与对照组相比差异有统计学意义（7．60±2．40）％比（0．70±0．64）％，P〈0．05]。对照组细胞的CD95与Bel-2表达无相关，而模型组CD34＋CD45＋和CD34＋CD45low细胞中，CD95与Bcl-2表达均呈负相关（r分别为-0．93和-0．81，P〈0．05）。结论冉生障碍性贫血模型小鼠中，骨髓中造血细胞的比例下降，有核细胞和CD34＋细胞的CD95表达比例升高，凋产明显，针对不同的凋亡指标进行相应捌节，可能是有效治疗再生障碍性贫血的途径之一。

Objective To investigate the expressions of CD95 and Bcl- 2 in bone marrow haemopoietic cells from mice with aplastic anemia and their relationship. Methods The mouse model of aplastic anemia was established by irradiation and immuno- mediation. Flow cytometry was employed to analyze the CD34 ＋ cells, CD45 ＋ cells, as well as expressions of surface CD95 and intracellular Bcl-2. Results The ratio of CD34＋ cells with low expresson of CD45 （CD34＋ CD45low） cells in the bone marrow was significantly lower in model group than that in control group [ （0.85±0.19）% vs （1.21±0.28）%, P〈 0.05 ]. The ratio of CD95 expression in model group was increased significantly on nucleated cells compared to control group [ （66.30±7.68）% vs （42.78±15.12）%], on CD34＋CD45＋ cells [ （69.21±9.36）% vs （22.31±3.33）%], and on CD34＋CD45 low cells [ （53.70±16.46）% vs （7.68±4.42）%1, respectively, all P〈0.01. The ratio of Bel-2 expression appeared comparable on different cells except on CD34＋CD45 low cells, which was （7.60±2.40） % in the model group and （0.70±0.64）% in control group with significant difference （P〈0.05）. The expressions of CD95 was not correlated with Bcl-2 in control group, but CD95 was negatively correlated with Bcl-2 on CD34＋CD45＋cells （r=-0.93, P〈0.05）and CD34＋CD45 low cells （r=-0.81, P〈0.05） of model group. Conclusions Mice with aplastic anemia showed lower ratio of haemopoietic cells, higher expression ratio of CD95 on nucleated and CD34＋ cells in bone marrow, and obvious apoptosis. Regulation targeting at different markers of apoptosis may be helpful tot effective treatment of aplastic anemia.