Understanding IgE Biology

了解 IgE 生物学

• 批准号: 10396243
• 负责人: Duane R. Wesemann
• 金额: $ 30万
• 依托单位: BRIGHAM AND WOMEN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-07-01 至 2022-03-09
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10396243
• 关键词: Affinity; Allergens; Allergic; Allergic Disease; Allergic inflammation; Alternative Splicing; Anaphylaxis; Anatomic Models; Antibodies; Antigens; Apoptosis; Asthma; B-Cell Antigen Receptor; B-Lymphocytes; Basophils; Biological; Biology; Bone Marrow; Bone Marrow Aspiration; Cell Degranulation; Cell Lineage; Cell Surface Receptors; Cell physiology; Cell surface; Cells; Complex; Data; Development; Distal; Food; Food Hypersensitivity; Gene Expression Profiling; Geography; Health; Heavy-Chain Immunoglobulins; Human; Human Volunteers; Hypersensitivity; IgE; Immunity; Immunoglobulin Class Switching; Immunoglobulin Switch Recombination; Immunoglobulins; Individual; Inflammation; Inflammation Mediators; Interleukin-13; Interleukin-4; Knowledge; Lead; Literature; Location; Longevity; Mediating; Membrane; Memory; Memory B-Lymphocyte; Messenger RNA; Mission; Mus; Nature; Pathogenesis; Patients; Pattern; Peripheral; Plants; Plasma Cells; Plasmablast; Play; Process; Production; Property; Proteins; Public Health; RNA Splicing; Research; Role; Signal Transduction; Site; Source; Stimulus; Surface; Surface Immunoglobulins; Systemic disease; Testing; Tissues; United States National Institutes of Health; Variant; Work; Yang; antigen binding; base; cytokine; deep sequencing; density; disability; experimental study; genetic manipulation; insight; mast cell; pathogen; receptor density; response; transcriptomics

Project Summary IgE-mediated allergic disease is a growing problem. The pathogenesis of allergic disease requires that immunoglobulin (Ig) E (IgE) molecules be produced against what are otherwise usually innocuous substances. Upon activation in the setting of cytokines such as IL-4 or IL-13, B cells can undergo IgH CSR to IgE. IgE secreted from B lineage cells can, in the presence of cognate antigen, activate mast cells and basophils to release potent inflammatory mediators. While IgE responses can lead to protective immunity as a part of a specialized responses to multicellular pathogens or other noxious threats, they also underlie allergic disease. Allergic disease can be manifest by localized inflammation, or by multiorgan involvement, including deadly systemic anaphylactic reactions via IgE-sensitized mast cell degranulation. Thus, the production and dissemination of IgE play a significant role in dictating the strength and extent of tissue mast cell sensitization. It is therefore critical to understand not only how B cell IgE production is controlled, but also the principles underlying distribution of IgE from point of origin to distal sites throughout the body. The overall objective of this application is to understand biological aspects of IgE production and dissemination and to gain insights into how this is influenced in allergic disease. Emerging literature and preliminary data from the applicant suggest a general hypothesis that biological constraints cooperate to restrict IgE dissemination under homeostatic conditions, and that accumulation of bone marrow IgE LLPCs is an aberrancy underlying systemic manifestations of allergic disease. This hypothesis will be tested by pursuing three specific aims, which are: 1) to determine the mechanisms of IgE expression dynamics on IgE B cell function; 2) to elucidate mechanisms underlying IgE distribution from point of origin to effector sites; and 3) to characterize IgE plasma cells in allergic patients. Under the first aim, IgE mRNA splicing and IgE surface density will be genetically perturbed to examine the hypothesis that mRNA production away from the mIg splice variant (i.e. the BCR variant) restricts the number and longevity IgE expressing cells, thus constraining IgE secretion largely to the insult site. Under the second aim, models of anatomic location-specific allergic challenge will be deployed to examine the degree to which IgE distribution is locally biased, and the role of B cells in this process. Under the third aim, bone marrow aspirations from healthy and allergic individuals will be obtained for IgH isotype-resolved deep sequencing as well as single cell transcriptomics to elucidate the cellular sources and biological properties of IgE in patients with long-standing severe allergies. This contribution is significant because it is expected to elucidate a more complete picture of how IgE responses are regulated. Ultimately, such knowledge has the potential to inform the development of new strategies that will help to reduce the growing problem of allergic disease.

项目总结