Role of TIM Molecules in Regulatory and Inflammatory B cells in Allo andAutoimmunity

除了体液免疫外，B细胞还通过抗原在塑造T效应反应中发挥重要作用 呈现、共刺激和细胞因子的产生。因此，B细胞耗尽可以改善自身免疫性糖尿病 和小鼠的关节炎，并迅速改善人类的RA和MS，结果与跌倒无关 自身抗体。相比之下，在人类和小鼠中，B细胞耗尽也会恶化自身免疫力，并可能 促进肾移植和心脏移植患者的急性排斥反应和慢性血管病变。这些 研究表明，B细胞可以增强或抑制炎症反应。在这方面，转让 不同的B细胞亚群可以通过IL-10抑制自身免疫和同种异体移植排斥反应，以及越来越多的其他 机械装置。然而，缺乏这些Bregs的通用表型或主要转录因子(Tf) 阻碍了赛场。目前尚不清楚这些不同的细胞是不同的还是相互关联的，或者是什么调节了 它们的分化或细胞因子的表达。我们的初步数据表明：1)TIM-1是一种包容性标记 IL-10+Bregs。2)B细胞上完整的TIM-1信号调节转录因子和多种调控因子的表达 分子(“调节模块”)。这使我们能够测试它们在Breg分化和功能中的作用。3)我们还 显示CpG激活的Pro-B细胞在成熟Breg后代的介导下，转移能力超过了抑制能力 在不同的位置表现出不同的作用机制。祖代和子代都是Tim-1+， 这使我们能够研究TIM-1和TFS在Breg分化和调节模块表达中的作用。 在自身免疫和感染环境中，B细胞也可以表达各种促炎细胞因子 强烈促进炎症反应。这种效应B细胞(Beff)的表型尚未确定， 目前还不清楚所描述的各种细胞是不同的还是相互关联的。Beff生物学的主要方面 是完全未知的，包括分化和细胞因子的表达是如何调节的。我们有 研究发现：1)TIM-4可鉴定BEF能表达干扰素γ和IL-17，并能加速同种异体移植排斥反应。2)IL-17 值得注意的是，它既是一种有效的效应细胞因子，也是BeFF炎性疾病发展所必需的 程序。B细胞IL-17的丧失不仅逆转了它们的炎症作用，还抑制了免疫反应， 促进同种异体移植耐受。3)TIM-4结扎可抑制促炎细胞因子的表达。 基于我们新的初步数据，PPG将利用自身免疫和同种异体移植模型来测试 中心假设TIM-1和TIM-4分别是Bregs和BeFf的统一标记，并调节 转录因子和其他对其发育和功能至关重要的分子的表达。这个问题将在 3个互动和相互支持的项目：项目1：TIM-1和Bregs在宽容和自动化方面的作用 项目2：TLR激活的TIM-1+ProB细胞在移植中的免疫调节；以及项目3： 同种异体免疫反应中TIM-4所定义的炎性B细胞这一理解是发展的关键 临床相关的方法，选择性地靶向Beff和Bregs，以增强或抑制免疫反应。

In addition to humoral immunity, B cells play an important role shaping T effector responses through antigen presentation, costimulation, and cytokine production. Thus, B cell depletion ameliorates autoimmune diabetes and arthritis in mice, and rapidly improves RA and MS in humans, and outcomes do not correlate with fall in autoantibodies. In contrast, in both humans and mice, B cell depletion can also worsen autoimmunity, and can promote acute rejection and chronic vasculopathy in renal and cardiac transplant patients, respectively. These studies indicate that B cells can either enhance, or inhibit, inflammatory responses. In this regard, transfer of various B cell subsets can inhibit autoimmunity and allograft rejection through IL-10, and a growing list of other mechanisms. However, lack of a universal phenotype or master transcription factor (TF) for these Bregs has stymied the field. It is unknown whether these disparate cells are distinct or inter-related, or what regulates their differentiation or cytokine expression. Our preliminary data show that: 1) TIM-1 is an inclusive marker for IL-10+ Bregs. 2) Intact TIM-1 signaling on B cells regulates the expression of both TFs and various regulatory molecules (“regulatory module”). This allows us to test their role in Breg differentiation and function. 3) We also show that CpG-activated Pro-B cells transfer exceeding potent suppression, mediated by mature Breg progeny exhibiting different mechanisms of action in different locations. Both progenitors and progeny are TIM-1+, which allows us to examine the role of TIM-1 and TFs in Breg differentiation and regulatory module expression. B cells can also express various proinflammatory cytokines in autoimmune and infectious settings that strongly promote inflammatory responses. No phenotype for such effector B cells (Beff) has been established, and it is unclear whether the various cells described, are distinct or inter-related. Major aspects of Beff biology are completely unknown, including how differentiation and cytokine expression are regulated. We have discovered that: 1) TIM-4 identifies Beff that express IFNγ and IL-17 and accelerate allograft rejection. 2) IL-17 is notably, both a potent effector cytokine, and is also required for development of the Beff inflammatory program. Loss of B cell IL-17 not only reverses their inflammatory role, but also, inhibits the immune response, promoting allograft tolerance. 3) TIM-4 ligation inhibits proinflammatory cytokine expression. Based on our novel preliminary data, this PPG will utilize autoimmune and allograft models to test the central hypothesis that TIM-1 and TIM-4, respectively, are unifying markers for Bregs and Beff and regulate expression of TFs and other molecules important for their development and function. This will be addressed in 3 interactive and mutually supportive projects: Project 1: Role of Tim-1 and Bregs in Tolerance and Auto- immunity; Project 2: Immunoregulation by TLR-activated TIM-1+ ProB Cells in Transplantation; and Project 3: Inflammatory B Cells Defined by TIM-4 in the Alloimmune Response. This understanding is key to developing clinically relevant approaches to selectively target Beff and Bregs to enhance or inhibit the immune response.