Mechanisms of immune homeostasis and regulation of intraocular inflammation

先天淋巴细胞、单核细胞、调节性 T 细胞 (Treg) 和调节性 B 细胞 (Breg) 通过分泌 IL-10 和 IL-35 来抑制中枢神经系统自身免疫性疾病，例如葡萄膜炎或多发性硬化症。这些免疫抑制细胞因子的活性是通过 JAK/STAT 信号通路的激活介导的，并受到严格的调控。在这项研究中，我们试图鉴定体内产生两种细胞因子的主要细胞类型，并描述调节其产生的机制。 与先天性或Tregs相比，我们发现Bregs是眼部炎症疾病期间体内IL-35和IL-10的主要产生者。我们还发现 BATF、IFN 调节因子 (IRF)-4 和 IRF-8 转录因子被募集并与 il12a、ebi3 和/或 il10 位点的 AP1-IRF 复合元件 (AICE) 结合，表明这些转录因子通过活化的 B 细胞调节 IL-10 和 IL-35 的表达。我们还发现 STAT3 依赖和独立途径控制眼部炎症。这些研究表明，靶向 STAT3 通路和 BATF/IRF-4/IRF-8 轴可用于治疗调节 IL-10/IL-35-Bregs 的生理水平和眼部炎症。

Innate lymphocytes, monocytes, regulatory T cells (Tregs) and regulatory B cells (Bregs) suppress CNS autoimmune diseases such as Uveitis or Multiple Sclerosis by secreting IL-10 and IL-35. The activities of these immune suppressive cytokines are mediated through activation of JAK/STAT signaling pathway and are under stringent regulation. In this study, we sought to identify major cell types that produce both cytokines in-vivo and to characterize mechanisms that regulate their production. Compared to innate or Tregs we found that Bregs are the major producers of IL-35 and IL-10 in vivo during ocular inflammatory diseases. We also found that BATF, IFN regulatory factor (IRF)-4, and IRF-8 transcription factors are recruited and bind to AP1-IRF-composite elements (AICEs) of il12a, ebi3, and/or il10 loci, suggesting that these transcription factors regulate IL-10 and IL-35 expression by activated B cells. We also found that STAT3-dependent and independent pathways control ocular inflammation. These studies suggest that targeting STAT3 pathways and the BATF/IRF-4/IRF-8 axis can be exploited therapeutically to regulate physiological levels of IL-10/IL-35-Bregs and ocular inflammation.