Analysis of Fel d 1-specific T cells after airway allergen challenge in asthma

项目SUMIVIARY(请参阅说明)： 过敏性哮喘患者在实验室吸入变应原会导致哮喘的大多数表现，包括可逆性气流阻塞、AHR和呼吸道炎症。这种方法已经被用来研究嗜酸性粒细胞、T细胞和树突状细胞往返于骨髓的转运机制。 血液和呼吸道。目前的提案将利用这种过敏原特异性直接支气管挑战模型提供的独特机会，通过使用MHC II类过敏原四聚体试剂在局部支气管过敏原挑战前后在体外丰富和表征FEL d 1表位特异性T细胞。这一提议的首要假设是，变态反应原特异性T细胞的运输 (四聚体)从血液到呼吸道和骨髓与晚期哮喘反应的发生有关。这项研究将测量FEL-1特异性T细胞的频率，这些细胞如何在相关的隔室(血液、骨髓和呼吸道)之间运输，以及它们的功能表型如何随着变应原的挑战而改变。这项建议的具体目标是： 目的1：检测肺段变应原激发后血和呼吸道中FEL-1特异性(FEL-d-1-MHC-II类四聚体)T细胞的频率和功能表型。 目的：检测肺段变应原激发后骨髓中FEL-d1特异性(FEL-d1-MHC-II类四聚体)T细胞的频率和功能表型。 目的：在人类白细胞抗原-DR4转基因变态反应性呼吸道疾病小鼠模型中，测定吸入性变应原攻击后血液、呼吸道(BAL和消化肺组织)、引流淋巴结、脾和骨髓中FEL-1特异性(FEL-1 MHC II类四聚体)T细胞的频率和功能表型，并评价目前正在临床试验的人疫苗成分多肽免疫治疗对这些参数的影响。 这些研究的结果将有助于阐明过敏原特异性T细胞如何在哮喘的发病机制中发挥作用，并为开发合理的治疗干预方法提供信息。

PROJECT SUMIVIARY (See instructions): Allergen inhalation by atopic asthmatics in the laboratory results in most of the manifestations of asthma, including reversible airflow obstruction, AHR and airway inflammation. This methodology has been used to examine the mechanisms of eosinophil, T-cell, and dendritic cell trafficking to/from the bone marrow to/from the blood and to the airways. The current proposal will capitalize on the unique opportunity offered by this allergen-specific model of direct bronchial challenge, by using MHC class II allergen tetramer reagents to enrich and characterize, ex vivo, Fel d 1 epitope-specific T cells before and after a localized bronchial allergen challenge. The overarching hypothesis of this proposal is that trafficking of allergen-specific T cells (tetramer+) from the blood to the airways and bone marrow is associated with the development of the late asthmatic reaction. This study will measure the frequency of Fel d 1-specific T cells, how these cells traffic between relevant compartments (blood, bone marrow and airways) and how their functional phenotype changes in response to allergen challenge. The specific aims of this proposal are: Aim 1: To determine the frequency and functional phenotype of Fel d 1-specific (Fel d 1 MHC class II tetramer+) T cells in the blood and the airways following lung segmental allergen challenge. Aim 2: To determine the frequency and functional phenotype of Fel d 1-specific (Fel d 1 MHC class II tetramer+) T cells in the bone marrow following lung segmental allergen challenge. Aim 3: To determine the frequency and functional phenotype of Fel d 1-specific (Fel d 1 MHC class II tetramer+) T cells in the blood, the airways (BAL and digested lung tissue), the lymph nodes draining the airways, the spleen and the bone marrow following inhaled allergen challenge in an HLA-DR4-transgenic murine model of allergic airways disease, and to assess the effects of peptide immunotherapy, using components of a human vaccine currently in clinical trials, on these parameters. The results of these studies will help to clarify how allergen-specific T cells contribution to the pathogenesis of asthma and inform development of rational approaches to therapeutic intervention.