Neutrophil Chemotaxis in Autoinflammation

描述（由申请人提供）：自身炎症综合征包括一组异质性的遗传性疾病，其特征是涉及先天免疫系统细胞的无菌性炎症反复发作。这些疾病的一个特征是中性粒细胞异常浸润到组织中，这表明中性粒细胞运输或运动的缺陷可能有助于疾病的发病机制。炎症反应的关键步骤包括白细胞的极化和向趋化物方向的迁移。我们工作的长期目标是确定体外调节中性粒细胞趋化性的信号通路，并通过斑马鱼作为模型系统检查体内中性粒细胞趋化性和炎症，了解这些机制对慢性炎症性疾病的影响。了解调节中性粒细胞趋化性的基本机制应该为自身炎症综合征和其他炎症是发病机制核心的疾病状态提供治疗靶点。我们实验室最近的研究表明，钙依赖性蛋白酶calpain对中性粒细胞趋化性至关重要。我们最近的研究还表明，磷脂酰肌醇磷酸激酶PIPKIgamma与钙蛋白酶2相互作用，是趋化性所必需的。我们提出验证在自身炎症综合征中突变的PSTPIP1和其他蛋白调节对细胞迁移和趋化至关重要的信号通路的假设，包括由calpain 2和PIPKIgamma介导的新途径，从而影响体内中性粒细胞趋化和炎症。具体目的：1 .阐明calpain2和PIPKIgamma如何调节中性粒细胞趋化和炎症。我们提出验证calpain2和PIPKIgamma在调节中性粒细胞趋化性和炎症的正反馈回路中起作用的假设。2。研究在PAPA综合征中突变的衔接蛋白PSTPIP1如何调节中性粒细胞趋化性和炎症。我们建议研究calpain2和PSTPIP1之间的相互作用，以及它在中性粒细胞趋化和炎症中的作用。3。以斑马鱼为模型系统，在体内检测中性粒细胞趋化性和炎症反应。靶向和非靶向方法将用于识别中性粒细胞趋化和体内炎症相关的关键信号通路。我们建议表征斑马鱼PSTPIP1并建立自身炎症的疾病模型。

DESCRIPTION (provided by applicant): Autoinflammatory syndromes comprise a heterogeneous group of inherited disorders characterized by recurrent episodes of aseptic inflammation involving cells of the innate immune system. A hallmark of these disorders is the abnormal infiltration of neutrophils into tissues, suggesting that defects in neutrophil trafficking or motility may contribute to disease pathogenesis. Critical steps during the inflammatory response include leukocyte polarization and migration in the direction of chemoattractant. The long term goal of our work is to define signaling pathways that regulate neutrophil chemotaxis in vitro, and to understand the implications of these mechanisms to chronic inflammatory disease by using zebraflsh as a model system to examine neutrophil chemotaxis and inflammation in vivo. Knowledge of the basic mechanisms that regulate neutrophil chemotaxis should provide therapeutic targets for autoinflammatory syndromes and other disease states in which inflammation is central to pathogenesis. Recent studies from our laboratory demonstrate that the calcium-dependent protease calpain is critical for neutrophil chemotaxis. Our recent studies also show that the phosphatyidylinositol phosphate kinase, PIPKIgamma, interacts with calpain 2 and is required for chemotaxis. We propose to test the hypothesis that PSTPIP1 and other proteins mutated in autoinflammatory syndromes modulate signaling pathways critical for cell migration and chemotaxis, including a novel pathway mediated by calpain 2 and PIPKIgamma, thereby affecting neutrophil chemotaxis and inflammation in vivo. Specific Aims: I. Elucidate how calpain 2 and PIPKIgamma regulate neutrophil chemotaxis and inflammation. We propose to test the hypothesis that calpain 2 and PIPKIgamma function in a positive feedback loop that regulates neutrophil chemotaxis and inflammation. II. Examine how PSTPIP1, an adaptor protein mutated in PAPA syndrome, modulates neutrophil chemotaxis and inflammation. We propose to examine the interaction between calpain 2 and PSTPIP1, and its role during neutrophil chemotaxis and inflammation. III. Use zebraflsh as a model system to examine neutrophil chemotaxis and inflammation in vivo. Both targeted and non-targeted approaches will be used to identify key signaling pathways involved in neutrophil chemotaxis and inflammation in vivo. We propose to characterize zebrafish PSTPIP1 and develop disease models of autoinflammation.