Regulation of Treg activity by controlling FOXP3 expression

这项资助的目的是确定小分子来控制调节性T细胞（Treg）的活性， 用于小鼠和人foxp 3基因表达的报告系统。Treg最初被鉴定为抑制T细胞， 细胞和预防自身免疫性疾病必不可少。因此，增强Treg活性可以提供新的 在自身免疫性疾病中将免疫重编程为耐受性的治疗策略， 移植虽然Treg可以预防自身免疫性疾病，但Treg在自身免疫性疾病中有意想不到的贡献。 增加微生物（包括病毒和细菌）感染的风险并增加癌细胞的存活能力。 细胞毒性CD 8 + T细胞应答导致微生物病原体和癌细胞的清除，但这些 活动似乎被Treg抑制。最近的研究表明，在糖尿病患者中，Treg的频率增加。 微生物感染和癌症患者，在感染的组织、肿瘤和循环中。因此，抑制 Treg活性可能为传染病和癌症提供新的治疗策略。发展和 Treg的功能受转录因子FOXP 3的调控，表明我们可以操纵Treg的活性 通过控制FOXP 3基因的表达来治疗自身免疫性疾病、感染性疾病和癌症。 为此，我们和许多其他小组一直在研究Foxp 3表达的调控。foxp 3基因 表达通过位于启动子中的至少四个调控区和保守的非- 编码序列（CNS 1、CNS 2和CNS 3）。我们证明了cRel（启动子中）、NFAT和Smad 3（启动子中） CNS 1）以及STAT 5和AP 1（在CNS 2中）调节Foxp 3基因表达，并且激活Foxp 3的抑制剂 这些转录因子可以阻断Treg的发育和活性。然而，这些重要的转录 因子不仅调节Foxp 3基因表达，而且还调节抗微生物和抗肿瘤免疫应答， 这表明这些抑制剂不适用于治疗感染性疾病和癌症。自从Foxp 3 基因表达通过极其复杂的机制通过至少四个调节区进行调节， 寻找控制Foxp 3基因表达的小分子也很困难。为了解决这些问题，我们 产生用于小鼠和人foxp 3基因表达的报告系统。这些系统的能力是 通过使用参与Foxp 3基因表达的转录因子抑制剂进行验证，我们还发现， mTOR抑制剂Torin 1可以使用该系统增强FOXP 3基因表达。因此，我们将确定 更多潜在的小分子使用这些报告系统开发治疗策略， 传染病和癌症。

The objective of this grant is identifying small molecules to control activity of regulatory T cells (Treg) using reporter systems for mouse and human foxp3 gene expression. Treg are originally identified as suppressor T cells and essential in preventing autoimmune disease. Therefore, enhancing Treg activity may offer new therapeutic strategies in re-programing immunity towards tolerance in autoimmune diseases and transplantations. Although Treg prevent autoimmune disease, there is an unexpected contribution by Treg in enhancing risk of microbial (including viral and bacterial) infection and increasing cancer cell survivability. Cytotoxic CD8+ T cells response leads to clearance of microbial pathogens and cancer cells, but these activities seem to be suppressed by Treg. Recent studies show that there is an increased frequency of Treg in microbial infected and cancer patients, within infected tissues, tumors, and in circulation. Therefore, inhibiting Treg activity may offer new therapeutic strategies for infectious diseases and cancer as well. Development and function of Treg are regulated by a transcription factor FOXP3, indicating that we can manipulate Treg activity through controlling FOXP3 gene expression for therapies of autoimmune and infectious diseases and cancer. To this end, we and many other groups have been studying regulation of Foxp3 expression. Foxp3 gene expression is controlled through at least four regulatory regions located in the promoter and conserved non- cording sequences (CNS1, CNS2 and CNS3). We demonstrated that cRel (in promoter), NFAT and Smad3 (in CNS1) and STAT5 and AP1 (in CNS2) regulate Foxp3 gene expression, and that inhibitors for activation of these transcription factors can block development and activity of Treg. However, these important transcription factors do not only regulate Foxp3 gene expression but also anti-microbial and anti-tumor immune responses, suggesting that these inhibitors are not suitable for therapies of infectious disease and cancer. Since Foxp3 gene expression is regulated by extremely complicated mechanisms through at least four regulatory regions, seeking small molecules to control Foxp3 gene expression is also difficult. To resolve these problems, we generated reporter systems for mouse and human foxp3 gene expression. Ability of these systems are validated by using inhibitors of transcription factors involved in Foxp3 gene expression, and we also found that a mTOR inhibitor Torin1 could enhance FOXP3 gene expression using this system. We will, therefore, identify more potential small molecules using these reporter systems to develop therapeutic strategies for autoimmune and infectious diseases, and cancer.