Therapeutic Intervention of the JAK/STAT Pathway for Neuroinflammation

项目摘要/摘要 多发性硬化(MS)的特点是中枢神经系统局灶性炎性浸润、脱髓鞘病变和轴突 损伤，导致神经功能障碍。先天免疫和获得性免疫系统的细胞参与了MS 发病机制。多发性硬化症的特征还包括产生激活免疫细胞的细胞因子，包括干扰素、IL-6、GM-CSF、 IL-12和IL-23。JAK/STAT通路被细胞因子用来进行信号传递，对细胞的发育、调节起关键作用 和免疫反应的终止。在之前的资助期间，我们开发了一种实验性自身免疫模型 脑脊髓炎(EAE)，其中JAK/STAT通路在髓系细胞中异常激活， 对Th1和Th17细胞分化的影响。该模型表现为非典型EAE的非分辨形式。在这 在JAK/STAT通路高度激活的非典型模型中，我们证明了AZD1480，一种 JAK/STAT通路，抑制疾病严重程度，阻止免疫细胞进入中枢神经系统，抑制分化 在Th1和Th17细胞中，STAT激活减少，细胞因子/趋化因子的表达减少。此外，我们 我已经在其他四种EAE模型(经典、复发缓解(RR)、Th1或Th17的过继转移)中测试了AZD1480 细胞)，并观察到显著的临床疗效。另一种JAK/STAT抑制剂AZD5776也可以抑制EAE的临床症状。 我们假设，JAK/STAT通路的不适当激活促进了细胞的异常反应 先天和获得性免疫系统，导致多发性硬化症的神经炎症，并具有治疗作用 这一途径的干预将改变多发性硬化症的进展。在这个修订的、竞争性的更新中，我们将评估两个 在五种EAE模型中，不同的JAK抑制剂AZD1480和AZD5776。AZD1480是JAK1和JAK2的抑制剂，而AZD5776 抑制JAK1。在目标1中，靶向JAK/STAT通路在活动期EAE中的治疗效果(经典，非典型， RR)将被审查。我们将评估1)哪些JAK/STAT参与了疾病的发病机制；2)哪种细胞类型(S) (CD4+T细胞、巨噬细胞、小胶质细胞、DC)JAK/STAT通路的激活是有害的；3)分子基础 为了JAK抑制剂的治疗益处。在目标2中，JAK/STAT通路在调节 将测试Th1和Th17细胞的致病潜力。Th1和Th17细胞均具有诱导中枢神经系统的能力 自身免疫，但有不同的致病机制。我们的初步结果表明，AZD1480是有效的 抑制Th1和Th17诱导的EAE。我们将评估AZD1480/AZD5776在体内如何治疗 MOG免疫的背景调节Th1和Th17细胞的发育程序和/或致病性。在《目标3》中， JAK抑制剂AZD1480和AZD5776调节免疫细胞功能的机制将是 检查过了。用JAK抑制剂处理的NA小鼠的巨噬细胞和DC将对其抗原进行评估 呈现能力，分化为促炎或抗炎表型，以及潜在的神经保护 属性。来自JAK抑制剂处理的小鼠的CD4+T细胞将被检测其随后的分化能力 转化为致病和/或保护性T细胞亚群。这些研究将建立必要的临床前基础 最终在人类多发性硬化症中测试JAK/STAT通路的抑制剂。

PROJECT SUMMARY/ABSTRACT Multiple Sclerosis (MS) is characterized by focal inflammatory infiltrates of the CNS, demyelinating lesions and axonal damage, leading to neurologic dysfunction. Cells of the innate and adaptive immune system are involved in MS pathogenesis. MS is also characterized by production of cytokines that activate immune cells, including IFN-¿, IL-6, GM-CSF, IL-12 and IL-23. The JAK/STAT pathway is used by cytokines for signaling, and is critical for the development, regulation and termination of immune responses. In the previous funding period, we developed a model of Experimental Autoimmune Encephalomyelitis (EAE) in which the JAK/STAT pathway is aberrantly activated in myeloid cells, with functional consequences for Th1 and Th17 cell differentiation. This model presents as a non-resolving form of atypical EAE. In this atypical model with heightened activation of the JAK/STAT pathway, we demonstrate that AZD1480, an inhibitor of the JAK/STAT pathway, suppresses disease severity, prevents entry of immune cells into the CNS, suppresses differentiation of Th1 and Th17 cells, decreases STAT activation, and reduces expression of cytokines/chemokines. Furthermore, we have tested AZD1480 in four other EAE models (Classical, Relapsing-Remitting (RR), Adoptive Transfer of Th1 or Th17 cells) and observed striking clinical efficacy. Another JAK/STAT inhibitor, AZD5776, also inhibits EAE clinical symptoms. We hypothesize that inappropriate activation of the JAK/STAT pathway promotes aberrant responses of cells of the innate and adaptive immune systems, leading to the neuroinflammation seen in MS, and that therapeutic intervention of this pathway will alter the progression of MS. In this revised, competing renewal, we will evaluate two distinct JAK inhibitors, AZD1480 and AZD5776, in five EAE models. AZD1480 is a JAK1 and JAK2 inhibitor, and AZD5776 inhibits JAK1. In Aim 1, the therapeutic efficacy of targeting the JAK/STAT pathway in active EAE (classical, atypical, RR) will be examined. We will evaluate 1) which JAKs/STATs are involved in disease pathogenesis; 2) in which cell type(s) (CD4+ T-cells, macrophages, microglia, DCs) activation of the JAK/STAT pathway is detrimental; and 3) the molecular basis for the therapeutic benefit of the JAK inhibitors. In Aim 2, the role of the JAK/STAT pathway in regulating the pathogenic potential of Th1 and Th17 cells will be tested. Both Th1 and Th17 cells have the capacity to induce CNS autoimmunity, but have differential pathogenic mechanisms. Our preliminary results indicate that AZD1480 is effective in inhibiting both Th1-induced and Th17-induced EAE. We will assess how in vivo treatment with AZD1480/AZD5776 in the context of MOG-immunization regulates the developmental program and/or pathogenicity of Th1 and Th17 cells. In Aim 3, the mechanism by which the JAK inhibitors AZD1480 and AZD5776 regulate immune cell function will be examined. Macrophages and DCs obtained from na¿ve mice treated with JAK inhibitors will be evaluated for their antigen presentation capability, polarization into proinflammatory or anti-inflammatory phenotypes, and potential neuroprotective properties. CD4+ T-cells derived from JAK inhibitor treated mice will be examined for their subsequent ability to differentiate into pathogenic and/or protective T-cell subsets. These studies will establish the pre-clinical foundation necessary to ultimately test inhibitors of the JAK/STAT pathway in human MS.