重型再生障碍性贫血模型小鼠脾脏CD4＋CD25＋T细胞凋亡影响及机制研究  

Apoptosis and its mechanisms of spleen CD4 ＋ CD25 ＋ regulatory T cells in severe aplastic anemia mouse model L

作　　者：陆雯萍 林赠华[1] 刘红[1] 陆伟[1] 刘海燕[1] 王旭丽[1] 

机构地区：[1]南通大学附属医院血液内科,226001

出　　处：《中华血液学杂志》2013年第11期931-935,共5页Chinese Journal of Hematology

基　　金：国家自然科学基金（81070400）;江苏省医学创新团队与领军人才（LJ201136）;江苏省中医药局科技项目（LZ11096）;南通市科技计划社会发展项目（$2010023）;南通大学研究生科技创新计划（YKC12026）

摘　　要：目的探讨干扰素（IFN吖）联合白消安诱导建立的重型再生障碍性贫血（AA）模型小鼠脾脏中CD4＋CD25＋调节性T（Treg）细胞的凋亡情况以及可能的机制。方法应用IFN-γ腹腔注射联合白消安灌胃诱导建立BALB／c重型AA模型小鼠（联合组），以正常组、IFN—γ组和白消安组（各16只）为对照。采用免疫磁珠法分选各组小鼠脾脏Treg细胞，应用流式细胞术检测各组小鼠脾脏Treg细胞的分选纯度及凋亡率，通过Westernblot法检测各组小鼠脾脏Treg细胞的蛋白激酶B（Akt）和转化生长因子-β（TGF—β）的表达水平。结果联合组小鼠脾脏Treg细胞的凋亡率为（33．21±0．65）％，较正常组[（27．38±1．89）％]、IFN—γ组[（17．62±1．05）％]和白消安组[（21．58±0．64）％]升高，差异有统计学意义（P〈0．05），而Akt、TGF—D蛋白表达水平分别是0．30±0．05和0．17±0．05，较其他3组降低，差异有统计学意义（P〈0．05）。结论IFN-γ联合白消安诱导的重型AA模型小鼠的脾脏Treg细胞存在过度凋亡现象，这可能是AA患者Treg细胞减少的原因之一；而Akt和TGF．B的表达水平下调可能在其过度凋亡中起一定作用，相关实验结果可能为AA免疫治疗提供新的理论思路。Objective To explore the apoptosis and its mechanisms of spleen CD4＋CD25＋ regulatory T （Treg） cells in severe aplastic anemia （SAA） mouse model induced by interferon （IFN-γ） in combination with busulphan （BU）. Methods The BALB/c female mice SAA model was induced by intraperitoneal injection with IFN-γ and intragastric administration with BU （combined group, n=16）, with BU group （n=16）, IFN-γ group （n=16） and normal group （n=16） as controls. Spleen Treg cells were purified by using of immunomagnetic beads. Apoptosis was detected by flow cytometry. Akt and TGF-13 expression was measured by Western blot. Results Apoptosis of spleen Treg cells in combined group [ （33.21±0.65）%]was significantly higher than that in BU group [ （21.58±0.64）%], IFN-3, group [ （ 17.62± 1.05）% ], and control [ （27.38± 1.89）% ] （P 〈 0.05）. A significantly lower expression of Akt and TGF-β protein was also seen in combined group （0.30±0.05 and 0.171±0.05 ）, as compared to the other three groups （P 〈 0.05）. Conclusion Excessive apoptosis of Treg cells was found in SAA mouse model, which may be a cause of Treg cells decrease in patients with AA. The down-regulated expression of Akt and TGF-D could play a role in increased apoptosis of Treg cells. Our data may provide a new treatment strategy in AA.

关 键 词：贫血 再生障碍性 T淋巴细胞 调节性 细胞凋亡 蛋白质丝氨酸苏氨酸激酶 转化生长因子β 

分 类 号：R556.5[医药卫生—血液循环系统疾病]