The Role of CD11/CD Integrins In Experimental Asthma

描述(申请人提供)：哮喘是一种常见的问题，表现为病理性炎症性疾病的过程，其特点是发作性和 气流阻塞的可逆症状。这两个国家的流行率都在上升 美国和全世界都反映了一个日益严重的公共卫生问题。一 最近的估计表明，哮喘每年的总成本为58亿美元， 住院费用占总支出的一半以上。 传统的哮喘疗法在减少哮喘发病率方面成效有限。 发病率和死亡率，显然将需要新的治疗方法。 在过去的十年里，人们普遍认为哮喘是一种 炎症性疾病，似乎是由激活和增殖引起的 Th2淋巴细胞。治疗哮喘的一个潜在靶点包括 选择性抑制与Th2募集相关的黏附蛋白 进入呼吸道的细胞，如果没有这些细胞，哮喘就会消失 实验模型。初步数据强烈表明CD18的缺失 导致小鼠实验性哮喘表型完全丧失 模特。CD11/CD18整合素是异源二聚体跨膜蛋白 由可变的α(CD11a，b，c，d)亚基组成，与 共同的β-2(CD18)亚单位。CD11/CD18整合素在多种细胞上表达 白细胞和介导与血管内皮细胞的黏附相互作用 细胞外基质在暴露于任何一种物质后募集白细胞中的作用 大量的炎症刺激。该项目的目的是确定 CD11/CD18整合素在过敏性呼吸道疾病小鼠模型中的作用 使用CD18缺乏的小鼠，四个CD11中每一个都缺乏的小鼠 亚基，以及多种CD11整合素联合缺陷的小鼠。全 将用卵清蛋白和卵清蛋白的混合抗原免疫不同基因型的小鼠 烟曲霉培养滤液诱导实验性哮喘的实验研究 表型。要测量的参数将包括对以下各项的呼吸道反应 静脉注射乙酰胆碱，支气管肺泡灌洗嗜酸性粒细胞增多症，卵清蛋白- 特异性IgE产生和杯状细胞化生。酶联免疫点 (ELISPOT)检测将用于定量IL-4和干扰素-γ产生的T细胞 突变小鼠和野生型小鼠脾、肺组织细胞的亲缘关系 Th2细胞向外迁移的差异。免疫磁学过继转移 从免疫突变小鼠到淋巴细胞缺陷小鼠的纯化的CD4+T细胞 (RAG-/-)和对野生型小鼠的影响将阐明特定基因的影响 Th2淋巴细胞向肺转运的缺陷。体外T细胞 另外还将进行刺激以确定Th2的容量 在缺乏CD11整合素的情况下进行分化。

DESCRIPTION (provided by applicant): Asthma, a common problem that exemplifies a pathologic inflammatory disease process, is characterized by episodic and reversible symptoms of airflow obstruction. The increasing prevalence both in the United States and worldwide reflects a growing public health problem. One recent estimate suggests the total annual cost of asthma to be $5.8 billion, with hospitalization accounting for over half of total expenditures. Traditional therapies of asthma have had limited success in reduction of morbidity and mortality, and it is clear that novel therapies will be needed. Over the last decade it has become widely accepted that asthma is an inflammatory disease and appears to result from activation and proliferation of Th2 lymphocytes. One potential target for therapy of asthma includes the selective inhibition of adhesive proteins responsible for recruitment of Th2 cells into the airway, the absence of which results in abolition of asthma in experimental models. Preliminary data strongly suggest that absence of CD18 results in complete loss of the experimental asthma phenotype in a murine model. CD11/CD18 integrins are heterodimeric, transmembrane proteins consisting of a variable alpha (CDlla, b, c, d) subunit coexpressed with the common beta-2 (CD18) subunit. CD11/CD18 integrins are expressed on a variety of leukocytes and mediate adhesive interactions with endothelium and extracellular matrix in recruiting leukocytes following exposure to any of numerous inflammatory stimuli. The aim of this project is to determine the role of CDll/CD18 integrins in a murine model of allergic airway disease, using mice deficient in CD18, mice singly deficient in each of the four CD11 subunits, and mice with combined deficiencies in multiple CD11 integrins. All genotypes of mice will be immunized with a hybrid antigen of ovalbumin and culture filtrate from Aspergillus fumigatus to induce the experimental asthma phenotype. Parameters to be measured will include airway response to intravenous acetylcholine, bronchoalveolar lavage eosinophilia, ovalbumin- specific IgE production, and goblet cell metaplasia. Enzyme-linked immunospot (ELISPOT) assays will be used to quantitate IL-4 and IFN-gamma producing T cells in spleens and lungs of mutant and wild type mice to assess relative differences in Th2 cell emigration. Adoptive transfer of immunomagnetically purified CD4+ T cells from immunized mutant mice to lymphocyte deficient mice (RAG -/-) and to wild type mice will clarify the effects of specific gene deficiencies on Th2 lymphocyte trafficking to the lung. In vitro T cell stimulation will additionally be performed to determine the capacity for Th2 differentiation in the absence of each of the CD11 integrins.