Antigenic determinants of asthma-associated allergens for design of immunotherapy

用于免疫治疗设计的哮喘相关过敏原的抗原决定簇

• 批准号: 8086141
• 负责人: MARTIN D. CHAPMAN
• 金额: $ 32.11万
• 依托单位: INDOOR BIOTECHNOLOGIES
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-01 至 2011-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8086141
• 关键词: Accident and Emergency department; Admission activity; Affect; Allergen Immunotherapy; Allergens; Allergic; Allergic Disease; Allergic Reaction; Am 80; Amino Acids; Antibodies; Antibody Binding Sites; Antibody Formation; Area; Aspartic Endopeptidases; Asthma; Basophils; Binding; Biological Assay; Breathing; Cells; Child; Complex; Crystallization; Crystallography; Cysteine Protease; Dermatophagoides farinae antigen f 1; Dermatophagoides pteronyssinus; Dermatophagoides pteronyssinus antigen p 1; Development; Dictyoptera; Dimerization; Dose; Environment; Enzyme-Linked Immunosorbent Assay; Epitopes; Felis catus; Goals; Health; High Prevalence; Homologous Gene; House Dust Mite Allergens; Hypersensitivity; IgE; Immunoglobulin Fragments; Immunoglobulin G; Immunologics; Immunotherapy; Individual; Inflammatory Response; Lung; Lung Inflammation; Maps; Mediator of activation protein; Mites; Molecular; Monoclonal Antibodies; Nature; Papain; Patients; Pepsin A; Phage Display; Pichia; Process; Property; Recombinants; Reporting; Risk Factors; Site-Directed Mutagenesis; Structure; Surface; T-Cell Proliferation; T-Lymphocyte; Technology; Testing; Th2 Cells; Time; Vaccine Design; Vaccines; abstracting; allergen Bla g 2; base; cockroach allergen; cross reactivity; crosslink; cytokine; design; inner city; insight; mast cell; mutant; novel vaccines; public health relevance; pyroglyphid

DESCRIPTION (provided by applicant): Antigenic determinants of asthma-associated allergens for design of immunotherapy Project Summary/Abstract Allergic reactions to cockroach and dust mite are important health problems in the U.S. affecting up to 83% of asthmatic children in inner city areas and are a risk factor for emergency room admission with asthma. The main cockroach species in the U.S., Blattella germanica, produces Bla g 2 which induces sensitization at exposure levels 10-100 times lower than cat and mite allergens, and has the highest prevalence of sensitization among cockroach allergens (40-70%). Der p 1 and Der f 1 are cysteine proteases produced by the dust mites Dermatophagoides pteronyssinus and D. farinae, respectively. IgE sensitization to these Group 1 allergens is >80% among mite allergic patients. Proteolytic activity of Der p 1 may enhance IgE antibody production and contribute to lung inflammation in asthma but Bla g 2 is an inactive aspartic protease- homolog. The main goal of this project is to investigate the antigenic structure of proteolytic (mite Group 1) and non-proteolytic (Bla g 2) allergens associated with asthma. Allergens will be co-crystallized with monoclonal antibodies, and the key amino acids involved in antibody (IgE and mAb) binding will be identified. Alternatively, identification of IgE antibody binding epitopes will be performed by phage display technology. The specific aims are: 1) mapping of antigenic determinants in Bla g 2 by crystallography; 2) mapping of antigenic determinants of Group 1 mite allergens by crystallography and analysis of the structural basis for the cross-reactivity between Der p 1 and Der f 1; and 3) localization of the key amino acids involved in the antibody binding epitopes by site-directed mutagenesis studies and identification of hypoallergenic mutants with T cell reactivity that could be used for immunotherapy. IgE antibody binding to the epitope mutants will be analyzed by ELISA, multiplex array technology and cell mediator release assays. Mutants will be compared to select hypoallergenic forms for the design of vaccines for immunotherapy of mite and cockroach allergy. PUBLIC HEALTH RELEVANCE: Cockroach and mite allergy is associated with the development of asthma, which affects 17 million people in the U.S. The antigenic determinants of Bla g 2 and Group 1 mite allergens will be identified to elucidate the importance of the intrinsic properties of these allergens on allergic disease. Hypoallergenic mutants will be produced and tested for IgE antibody binding and T cell proliferation, and the information obtained will facilitate a rational design of allergy vaccines.

描述（由申请人提供）：用于免疫治疗设计的哮喘相关过敏原的抗原决定簇项目摘要/摘要在美国，对蟑螂和尘螨的过敏反应是重要的健康问题，影响到内城地区高达83%的哮喘儿童，并且是哮喘急诊室入院的危险因素。美国的主要蟑螂种类，德国小蠊产生Bla g 2，其在比猫和螨变应原低10-100倍的暴露水平下诱导致敏，并且在蟑螂变应原中具有最高的致敏流行率（40-70%）。Derp 1和Derf 1是由屋尘螨Dermatophagoides pteronyssinus和屋尘螨Dermatophagoides pteronyssinus产生的半胱氨酸蛋白酶。farinae，分别。在螨过敏患者中，对这些第1组过敏原的IgE致敏率>80%。Derp 1的蛋白水解活性可能增强IgE抗体的产生并促进哮喘中的肺部炎症，但Blag 2是一种无活性的天冬氨酸蛋白酶同源物。本项目的主要目的是研究与哮喘相关的蛋白水解（螨组1）和非蛋白水解（Bla g 2）过敏原的抗原结构。过敏原将与单克隆抗体共结晶，并将鉴定抗体（IgE和mAb）结合中涉及的关键氨基酸。或者，通过噬菌体展示技术进行IgE抗体结合表位的鉴定。具体目标是：（1）Bla g 2抗原决定簇的晶体学定位（2）第1组螨变应原抗原决定簇的晶体学定位及Der p 1与Der f 1交叉反应的结构基础分析;和3）通过位点定位抗体结合表位中涉及的关键氨基酸，定向诱变研究和鉴定可用于免疫治疗的具有T细胞反应性的低变应原突变体。IgE抗体与表位突变体的结合将通过ELISA、多重阵列技术和细胞介质释放测定法进行分析。将比较突变体以选择低变应原性形式，用于设计螨和蟑螂过敏的免疫疗法的疫苗。公共卫生相关性：蟑螂和螨过敏与哮喘的发生有关，哮喘影响美国1700万人。将鉴定Bla g 2和组1螨过敏原的抗原决定簇，以阐明这些过敏原的内在特性对过敏性疾病的重要性。将生产低变应原突变体，并检测IgE抗体结合和T细胞增殖，获得的信息将有助于合理设计过敏疫苗。