Phylogenetic Approach to Plant Allergy Vaccines

植物过敏疫苗的系统发育方法

• 批准号: 6723560
• 负责人: Randall M Goldblum
• 金额: $ 26.17万
• 依托单位: UNIVERSITY OF TEXAS MED BR GALVESTON
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-03-01 至 2008-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6723560
• 关键词: SDS polyacrylamide gel electrophoresis; active immunization; allergens; asthma; binding sites; cell proliferation; clinical research; complementary DNA; enzyme linked immunosorbent assay; genetic library; helper T lymphocyte; human subject; hypersensitivity; immune response; immunoglobulin E; immunotherapy; nucleic acid sequence; plant extracts; plant genetics; pollen; polymerase chain reaction; rhinitis; vaccine development; western blottings

DESCRIPTION (provided by applicant): Allergic diseases of the airways, including asthma and allergic rhinitis are increasing in industrialized countries, where up to 30% of some populations are now affected. Cedar pollen is a major cause of seasonal allergic rhinitis (pollinosis) in Central U.S.A, Southern Europe and Japan. Effective immunization holds the greatest promise for preventing and treating allergic diseases. Current immunotherapy is limited by the risk of producing IgE-mediated, localized or anaphylactic reactions. The hypothesis to be tested in this proposal is that the molecular biodiversity of plants can be used to identify natural sources of allergens with reduced capacity to bind IgE, while retaining their capacity to induce T-helper cell responses. The specific aims to test this hypothesis are to: 1) Create a library of genetic sequences for homologues of two major mountain cedar allergens, by PCR amplification and automated nucleotide sequencing of genomic and cDNA from up to 138 cedar / cypress species. 2) Identify within this library genetic variants of the allergens, in which the amino acid sequence of the IgE binding sites (epitopes) differ from those of the sensitizing allergens and use novel computational algorithms and automated homology modeling to determine in which variants the 3-D structures of one or more IgE epitopes are likely to be disrupted. 3) Express the genes for the selected variants of the allergens as fusion proteins and test their binding of serum IgE from cedar allergic patients from Central U.S.A, Southern Europe and Japan, their ability to induce degranulation of blood basophils from cedar-allergic patients, and to induce T-helper responses. These studies will be performed by an established, multidisciplinary team of immunologists, structural biologists and a botanist, who have experience in the discovery and characterization of cedar allergens. Successful completing these studies will result in a new generation of allergy vaccines, the efficacy of which can be tested, without expensive safety testing. A better understanding of the structural characteristics of allergenic epitopes will expedite the development of new vaccines against numerous allergens.

描述（由申请人提供）：气道的过敏性疾病，包括哮喘和过敏性鼻炎，在工业化国家正在增加，在这些国家，高达30%的人口现在受到影响。雪松花粉是美国中部、南欧和日本季节性过敏性鼻炎（花粉症）的主要原因。有效的免疫是预防和治疗过敏性疾病的最大希望。目前的免疫治疗受到产生ige介导、局部或过敏性反应的风险的限制。本提案中需要验证的假设是，植物的分子生物多样性可以用来识别与IgE结合能力降低的过敏原的天然来源，同时保留其诱导t辅助细胞反应的能力。验证这一假设的具体目的是：1)通过对多达138种雪松/柏树的基因组和cDNA进行PCR扩增和自动核苷酸测序，建立两个主要山雪松过敏原同源物的基因序列库。2)在该文库中识别出与致敏过敏原不同的IgE结合位点（表位）氨基酸序列的过敏原遗传变异，并使用新的计算算法和自动同源建模来确定哪些变异中一个或多个IgE表位的3-D结构可能被破坏。3)将选定的变异体基因表达为融合蛋白，检测其与美国中部、南欧和日本雪松过敏患者血清IgE的结合、诱导雪松过敏患者血液嗜碱性粒细胞脱粒和诱导t辅助反应的能力。这些研究将由一个由免疫学家、结构生物学家和一名植物学家组成的成熟的多学科团队进行，他们在发现和表征雪松过敏原方面有经验。成功完成这些研究将产生新一代的过敏疫苗，可以测试其功效，而无需进行昂贵的安全性测试。更好地了解致敏抗原表位的结构特征将加快针对众多过敏原的新疫苗的开发。