再生障碍性贫血（AA)是一种T细胞免疫稳态异常引起造血干细胞损伤的骨髓衰竭性疾病。Treg是一组维持机体免疫平衡的T细胞亚群，前期研究已发现儿童AA发病与Treg减少和功能缺陷相关。Blimp-1作为调控Treg的重要上游转录因子，通过IL-2负反馈环路及IL-10调控Treg功能，据此提出“Blimp-1通过IL-2及IL-10调控Treg介导AA 发病机制”的假设。拟在Blimp-1基因敲除AA小鼠模型和临床AA患儿样本中，检测Treg数量和功能以及Treg上Blimp-1、IL-2和IL-10 mRNA及蛋白表达水平，分析Blimp-1、Treg以及IL-2、IL-10与AA发病的相关性；观察IL-2干预Blimp-1表达前后IL-2、IL-10 mRNA及蛋白水平以及Treg的变化，以明确Blimp-1调控Treg的作用机制及在AA发病中的作用，对提高儿童AA疗效具有重要意义。

Aplastic anemia(AA) is a bone marrow failure syndrome mainly due to the abnormal T cell immune. Regulatory T cells (Treg) is a T cell subgroup maintaining immune homeostasis. Our previous studies have confirmed that the frequency of Treg was lower and the function of Treg was impaired in both peripheral blood and bone marrow in children with AA. As an important upstream transcription factor of Treg, Blimp-1 regulates and maintains the function of Treg through the IL-2 negative feedback loop and IL-10. And thus, we hypothesized that the abnormal regulation of Blimp-1 on Treg might be a new pathogenesis of AA in children. So we want to establish an AA mice model with Blimp-1 gene knockout and collect the peripheral blood and bone marrow from children with AA, detecting the frequency and function of Treg and the expression level (mRNA and protein) of Blimp-1, IL-2, IL-10 on Treg, to analyze the correlation of Blimp1, Treg, IL-2, IL-10 and AA. In addition, we give IL-2 or IL-2 antagonist to induce or block the Blimp1, detecting the changes of the expression level(mRNA and protein) of IL-2, IL-10 and the frequency and function of Treg to clarify the mechanism of Blimp-1 regulating Treg and its role in the pathogenesis of AA, which will make great importance in improving the clinical efficacy for AA in children.