Chemical Mediators of Acute Pulmonary Disorders

描述（由申请人提供）： 这是一个持续的，合作的努力，以了解调节肥大细胞（MC）相关的效应器功能和相关性，这些过程与哮喘。MC在造血效应细胞中是独特的，因为它们在肺和其他血管化组织中的组成性驻留，以及它们对先天性和适应性免疫应答的传入和传出阶段的显著贡献。该项目的中心假设是，MC，凭借其组成性和诱导性效应途径，形成先天性和获得性免疫反应和哮喘的临床表现之间的功能性桥梁。纯化的重组MC类胰蛋白酶的可用性和小鼠品系的开发缺乏必要的酶合成serglyin蛋白聚糖允许蛋白聚糖在调节的各种功能的胰蛋白酶在体外和体内的作用的研究。一种新的体外方法将被用来定义的机制，GP 49 B1，一个反调节受体轴承免疫酪氨酸为基础的抑制基序（ITIM），通过机械调节MC激活不同的受体，以限制MC依赖性病理过敏和先天性免疫反应。将鉴定小鼠2号和6号染色体上相互作用以在A/J小鼠中赋予固有MC依赖性AHR的基因，并且将通过将MC过继转移至由于c-kit酪氨酸激酶突变而导致MC缺陷的A/J小鼠中来证实该表型的MC依赖性。分别缺乏造血PGD 2合酶（PGDS）和LTC 4合酶（LTC 4S）的小鼠品系，以及缺乏PGD 2和LTC 4的每种受体的敲除品系，将用于定义这些类花生酸在体外和体内的互补和反调节功能。支气管保护性类花生酸、PGE 2和诱导型PGE 2激酶在阿司匹林不耐受性哮喘（AIA）中的作用将采用一种新的体外方法从特征明确的AIA供体中培养人MC（hMC）。在相关酶和PGE受体的缺失将促使重新测序发现多态性变体。负责PGE 2对hMC激活的抑制作用的受体和机制将被定义。这些研究共同提供了关键的信息，了解生化和遗传调控的关键MC相关的效应功能，并确定其在控制内源性AHR，炎症和组织修复后，过敏和先天性免疫反应，可能有助于哮喘的病理生理学的作用。

DESCRIPTION (provided by applicant): This is a continuing, collaborative effort to understand the regulation of mast cell (MC)-associated effector functions and the relevance of these processes to asthma. MCs are unique among hematopoietic effector cells for their constitutive residence in the lung and other vascularized tissues, and their prominent contribution to both afferent and efferent phases of innate and adaptive immune responses. The central hypothesis of this Program Project is that MCs, by virtue of their constitutive and inducible effector pathways, form a functional bridge between innate and acquired immune responses and the clinical expression of asthma. The availability of purified recombinant MC tryptases and the development of mouse strains lacking the enzymes necessary to synthesize serglyin proteoglycans permits study of the role of proteoglycans in regulating the diverse functions of tryptases in vitro and in vivo. A novel in vitro approach will be used to define the mechanism by which GP49B1, a counterregulatory receptor bearing immunotyrosine-based inhibitory motifs (ITIMs), regulates MC activation through mechanistically diverse receptors to limit MC-dependent pathology in both allergic and innate immune esponses. The genes on mouse chromosomes 2 and 6 that interact to confer intrinsic MC-dependent AHR in A/J mice will be identified, and the MC-dependency of this phenotype will be confirmed with adoptive transfer of MCs into A/J mice rendered MC-deficient due to a mutation in the c-kit tyrosine kinase. Mouse strains lacking hematopoietic PGD2 synthase (PGDS) and LTC4synthase (LTC4S), respectively, as well as knockout strains lacking each receptor for PGD2 and LTC4, will be used to define the complementary and counterregulatory functions of these eicosanoids in vitro and in vivo. The role of the bronchoprotective eicosanoid, PGE2, and inducible PGE2 synthases in aspirin intolerant asthma (AIA) will be studied using a novel in vitro approach to the development of human MCs (hMCs) from well-characterized donors with AIA. Abnormalities in relevant synthases and PGE receptors will prompt resequencing for discovery of polymorphic variants. The receptors and mechanisms responsible for the inhibitory effects of PGE2 on hMC activation in vitro will be defined. These studies collectively provide information critical to understanding the biochemical and genetic regulation of key MC-associated effector functions, and defining their role in the control of intrinsic AHR, inflammation, and tissue repair subsequent to both allergic and innate immune responses that likely contribute to the pathophysiology of asthma.