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

拟议的变应原表位研究和验证中心将使用独特的主要组织相容性(MHO)类四聚体，其中包含主要猫变应原Pel d 1的T细胞表位，以便在干预(1)由Pel d 1的免疫优势T细胞表位组成的多肽治疗性疫苗和(2)用猫挑战支气管(节段性)变应原之前和之后表征变应原特异性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(行政核心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的。 项目1(多肽免疫治疗)特定目标1将使用四聚体来丰富和鉴定来自已完成的多肽疫苗临床试验的冷冻外周血单核细胞(PBMC)样本中的过敏原特异性T细胞(治疗前和治疗后)。项目1特定目标2将采用多肽免疫疗法的前瞻性临床试验，以产生更大的血液样本，以便更深入地分析 变应原特异性(四聚体)T细胞的频率和功能表型。项目1的具体目标3将解决MHC分子的多肽亲和力与疗效之间的关系。这一目标将在人类白细胞抗原DR转基因小鼠身上实现，因为提出的研究问题在人类受试者身上无法得到回答。项目2(支气管变应原挑战)特殊目标1和2将涉及48名儿童过敏性哮喘患者的节段性变应原挑战。在过敏原激发前和激发后24小时分别采集血液和骨髓样本。支气管肺泡灌洗液(BAL)的样本将在攻击后24小时从生理盐水和过敏原攻击的肺叶中恢复。在所有样品中。PEL D 1四聚体将被用来丰富和鉴定变应原特异性T细胞，以进一步分析每个解剖间隔中的频率和功能表型。项目2的特殊目标3将在人类白细胞抗原DR4转基因小鼠身上进行类似的分析，但将分析人类受试者无法进入的其他几个部分(脾、肺组织、除血液、BAL和骨髓外的引流淋巴结)。此外，这一目的将评估多肽免疫疗法在小鼠变应原攻击模型中的效果。

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