The effect of peptide therapy and allergen provocation on Fel d1-specific T Cells

拟议的过敏原表位研究和验证中心将使用含有主要猫过敏原Pel d 1的T细胞表位的独特的主要组织相容性（MHO）II类四聚体，以表征在用（1）基于肽的治疗性疫苗（由Pel d 1的免疫显性T细胞表位组成）和（2）猫支气管（节段性）过敏原激发干预前后的过敏原特异性T细胞。 过敏原提取物。提出了两个研究项目和两个核心。核心（管理核心A和临床试验核心B）将促进和支持研究项目的科学目的和目标。 项目1（肽免疫疗法）特异性目标1将使用四聚体富集和鉴定来自肽疫苗已完成临床试验的冷冻外周血单核细胞（PBMC）样本（治疗前与治疗后）中的过敏原特异性T细胞。项目1具体目标2将采用肽免疫疗法的前瞻性临床试验，以产生更大的血液样本，用于更深入的分析。 过敏原特异性（四聚体+）T细胞的频率和功能表型。项目1具体目标3将解决肽对MHC分子的亲和力与疗效之间的关系。该目的将在HLA-DR转基因小鼠中进行，因为所提出的研究问题无法在人类受试者中回答。项目2（支气管过敏原激发）具体目标1和2将涉及48名猫过敏性哮喘受试者的节段性过敏原激发。在过敏原激发前和激发后24小时采集血液和骨髓样本。攻毒后24小时，从生理盐水和过敏原攻毒的肺叶中回收支气管肺泡灌洗液（BAL）样本。在所有样本中。Pel d 1四聚体将用于富集（适当的）和鉴定变应原特异性T细胞，以进一步分析每个解剖区室中的频率和功能表型。项目2特定目标3将进行类似的分析，但在HLA-DR 4转基因小鼠中进行，但将分析人类受试者中无法获得的其他几个区室（除血液、BAL和骨髓外，还包括脾脏、肺组织、引流淋巴结）。此外，本研究还将评估肽免疫疗法在小鼠过敏原激发模型中的作用

The proposed Allergen Epitope Research and Validation Center will use unique Major Histocompatibility (MHO) class II tetramers containing T cell epitopes of the major cat allergen Pel d 1 in order to characterize allergen-specific T cells before and after intervention with (1) a peptide-based therapeutic vaccine comprised of immunodominant T cell epitopes of Pel d 1, and (2) bronchial (segmental) allergen challenge with cat allergen extract. Two research Projects and two Cores are proposed. The Cores (Administrative Core A and Clinical Trial Core B) will facilitate and support the scientific objectives and goals of the research Projects. Project 1 (peptide immunotherapy) Specific Aim 1 will use tetramers to both enrich and identify allergenspecific T cells in frozen peripheral blood mononuclear cell (PBMC) samples (before vs. after treatment) from a completed clinical trial of the peptide vaccine. Project 1 Specific Aim 2 will employ a prospective clinical trial of peptide immunotherapy to generate larger blood samples for more in depth analysis of the frequency and functional phenotype of allergen-specific (tetramer+) T cells. Project 1 Specific Aim 3 will address the relationship between peptide affinity for MHC molecules and efficacy. This Aim will be performed in HLA-DR transgenic mice as the research question posed cannot be answered in human subjects. Project 2 (bronchial allergen challenge) Specific Aims 1 & 2 will involve segmental allergen challenge in 48 catallergic asthmatic subjects. Samples of blood and bone marrow will be taken before and 24 hours after allergen challenge. Samples of bronchoalveolar lavage (BAL) fluid will be recovered from saline and allergen challenged lung lobes 24 hours after challenge. In all samples. Pel d 1 tetramers will be used to enrich (were appropriate) and identify allergen-specific T cells for further analysis of frequency and functional phenotype in each anatomical compartment. Project 2 Specific Aim 3 will perform a similar analysis but in HLA-DR4 transgenic mice, but will analyze several other compartments not accessible in human subjects (spleen, lung tissue, draining lymph nodes in addition to blood, BAL and bone marrow). Additionally this Aim will assess the effects of peptide immunotherapy in the murine allergen challenge model