Roles of the Src-Family Kinases LynA and LynB in Macrophage Inflammatory Signaling

摘要 自身免疫性疾病青少年特发性关节炎（JIA），导致关节，眼睛和骨骼损伤， 慢性疼痛是美国最常见的儿童慢性疾病。JIA患者关节液 含有大量的巨噬细胞免疫细胞，并能驱动巨噬细胞分泌炎症因子 这种疾病目前针对JIA的疗法阻断了这种炎症信号，但不能区分疾病- 相关的炎症信号和对感染的正常免疫反应。因此，压制- 抗微生物免疫是这些现有疗法的严重副作用。我们发现了一个信号机器人- 巨噬细胞通过蛋白LynA进行过敏性炎症信号传导，但 病原体识别并不严格要求。我们现在也产生了第一个LynA-/-小鼠，并提出 测试LynA调节途径是否有希望作为一种新的治疗靶点， 炎症巨噬细胞信号传导而不抑制免疫系统。我们的长期目标是 开发专门针对病理性巨噬细胞的新治疗方法。为了评估跨- 我们的信号发现的潜在作用，我们的目标是测试LynA在分离的巨噬细胞中的作用，在小鼠中， 炎症性关节炎、感染和人类JIA患者的样本中。具体而言，我们建议：1） 检查巨噬细胞中LynA缺失的影响：我们将使用最近在我们的研究中开发的新型LynA-/-小鼠。 实验室测试LynA对骨髓源性巨噬细胞中信号传导的独立贡献。我们 预测LynA-/-巨噬细胞对小刺激的反应迟钝，但对大刺激的反应正常， 病原体模拟刺激2)检查LynA在小鼠炎症性关节炎和感染中的作用：我们将 评估野生型和LynA-/-小鼠中炎性关节炎以及真菌和细菌感染的进展。 我们还将分析巨噬细胞功能的标志物，并测试脾脏和滑膜MAC中的信号反应。 Rolling来评估LynA在炎症中的作用。我们预测LynA-/-小鼠的关节炎不太严重， 但对感染的反应正常。3)测试炎症驱动的LynA上调和信号- 在人类巨噬细胞中：我们假设，与小鼠一样，JIA影响关节的炎症诱导LynA 在人巨噬细胞中上调。我们将测试JIA患者的滑液是否诱导LynA上调， 和巨噬细胞超敏反应，以及这种病理功能是否被敲低 Lyna表情。我们预测JIA滑液将诱导人类巨噬细胞中LynA的上调， 导致超敏感信号。该项目将受益于我们在巨噬细胞信号传导和关闭的专业知识 与以研究为导向的儿科流变学诊所和该中心的其他研究人员合作， 明尼苏达大学的免疫学。这些研究将确定靶向LynA的可行性， velop是JIA和其他巨噬细胞驱动的炎症性疾病的更安全、有针对性的治疗选择。

ABSTRACT The autoimmune disease juvenile idiopathic arthritis (JIA), which causes joint, eye, and bone damage and chronic pain, is the most common chronic childhood disease in the United States. Joint fluid from JIA patients contains large numbers of macrophage immune cells, and macrophage secretion of inflammatory factors drives the disease. Current therapies for JIA block this inflammatory signaling but do not discriminate between disease- associated inflammatory signaling and the normal immune response to infection. Therefore, suppression of an- timicrobial immunity is a severe side effect of these existing therapies. We have discovered a signaling mecha- nism through the protein LynA that is required for hypersensitive inflammatory signaling by macrophages, but is not strictly required for pathogen recognition. We have now also generated the first LynA-/- mice and propose to test whether the LynA regulatory pathway has promise as a novel therapeutic target, to specifically suppress inflammatory macrophage signaling without suppressing the immune system generally. Our long-term goal is to develop new therapeutic approaches targeted specifically to pathological macrophages. To evaluate the trans- lational potential of our signaling discovery, we aim to test the role of LynA in isolated macrophages, in mouse inflammatory arthritis, in infection, and in samples from human JIA patients. More specifically, we propose to: 1) Examine the effect of LynA deletion in macrophages: We will use novel LynA-/- mice developed recently in our laboratory to test the independent contributions of LynA to signaling in bone-marrow-derived macrophages. We predict that LynA-/- macrophages will have blunted responses to small stimuli but normal responses to large, pathogen-mimetic stimuli. 2) Examine the role of LynA in mouse inflammatory arthritis and infection: We will assess the progression of inflammatory arthritis and fungal and bacterial infections in wild-type and LynA-/- mice. We will also analyze markers of macrophage function and test signaling responses in splenic and synovial mac- rophages to assess the role of LynA in inflammation. We predict that LynA-/- mice will develop less severe arthritis than wild-type mice but respond normally to infection. 3) Test inflammation-driven LynA upregulation and signal- ing in human macrophages: We hypothesize that, as in mice, inflammation in JIA-affected joints induces LynA upregulation in human macrophages. We will test whether synovial fluid from JIA patients induces LynA upreg- ulation and macrophage hypersensitivity and whether this pathological function is suppressed by knocking down LynA expression. We predict that JIA synovial fluid will induce upregulation of LynA in human macrophages, leading to hypersensitive signaling. This project will benefit from our expertise in macrophage signaling and close collaborations with the research-oriented Pediatric Rheumatology Clinic and other investigators in the Center for Immunology at the University of Minnesota. These studies will establish the feasibility of targeting LynA to de- velop safer, targeted treatment options for JIA and other macrophage-driven inflammatory diseases.