The Role of CD11/CD Integrins In Experimental Asthma

描述（由申请人提供）：哮喘，一种常见的问题， 一种病理性炎症疾病过程，其特征在于发作性和 可逆的气流阻塞症状。无论是在 美国和世界范围内反映了一个日益严重的公共卫生问题。一 最近的估计表明每年哮喘的总费用为58亿美元， 住院费用占总支出的一半以上。 哮喘的传统疗法在减少哮喘发作方面的成功有限。 发病率和死亡率，很明显，需要新的治疗方法。 在过去的十年里，人们已经广泛接受哮喘是一种 炎症性疾病，似乎是由活化和增殖引起的 Th 2淋巴细胞治疗哮喘的一个潜在靶点包括 选择性抑制负责募集Th 2的粘附蛋白 细胞进入气道，缺乏这种细胞会导致哮喘的消除， 实验模型初步数据强烈表明，缺乏CD 18 导致小鼠实验性哮喘表型完全丧失 模型CD 11/CD 18整合素是异二聚体跨膜蛋白 由与共表达的可变α（CDlla、B、c、d）亚基组成 共同β-2（CD 18）亚单位。CD 11/CD 18整合素表达于多种 介导与内皮细胞的粘附相互作用， 细胞外基质在招募白细胞后暴露于任何 大量的炎症刺激。该项目的目的是确定 CD 11/CD 18整联蛋白在变应性气道疾病鼠模型中的作用， 使用缺乏CD 18的小鼠，单独缺乏四种CD 11的小鼠， 亚基和多种CD 11整合素联合缺陷的小鼠。所有 基因型的小鼠将用卵清蛋白的杂合抗原免疫， 烟曲霉培养滤液诱发实验性哮喘 表型待测量的参数将包括气道反应， 静脉乙酰胆碱，支气管肺泡灌洗嗜酸性粒细胞增多，卵清蛋白- 特异性IgE产生和杯状细胞化生。酶联免疫斑点 将使用ELISPOT（酶联免疫斑点法）测定来定量产生IL-4和IFN-γ的T细胞 突变型和野生型小鼠的脾和肺中的细胞，以评估相对 Th 2细胞迁移的差异。免疫磁性连续转移 从免疫突变小鼠到淋巴细胞缺陷小鼠的纯化的CD 4 + T细胞 (RAG-/-）和野生型小鼠的研究将阐明特定基因 Th 2淋巴细胞运输到肺部的缺陷。体外T细胞 将另外进行刺激以确定Th 2的能力 在不存在每种CD 11整联蛋白的情况下的分化。

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.