Abstract:
Food allergy, a group of adverse immune responses to normally innocuous food protein antigens, is an increasingly prevalent public health issue. The most common form is IgE-mediated food allergy in which food antigen-induced crosslinking of the high-affinity IgE-receptor, FcεRI, on the surface of mast cells triggers the release of inflammatory mediators that contribute to a wide range of clinical manifestations, including systemic anaphylaxis. Mast cells also play a critical function in adaptive immunity to foods, acting as adjuvants for food-antigen driven Th2 cell responses. While the diagnosis and treatment of food allergy has improved in recent years, no curative treatments are currently available. However, there is emerging evidence to suggest that both allergen-specific IgA and IgG antibodies can counter the activating effects of IgE antibodies on mast cells. Most notably, both antigen-specific IgA and IgG antibodies are induced in the course of oral immunotherapy. In this review, we highlight the role of mast cells in food allergy, both as inducers of immediate hypersensitivity reactions and as adjuvants for type 2 adaptive immune responses. Furthermore, we summarize current understanding of the immunomodulatory effects of antigen-specific IgA and IgG antibodies on IgE-induced mast cell activation and effector function. A more comprehensive understanding of the regulatory role of IgA and IgG in food allergy may provide insights into physiologic regulation of immune responses to ingested antigens and could seed novel strategies to treat allergic disease.
摘要:
食物过敏,一组对通常无害的食物蛋白抗原的不良免疫反应,是一个日益普遍的公共卫生问题。最常见的形式是IgE介导的食物过敏,其中食物抗原诱导的高亲和力IgE受体交联,FcεRI,在肥大细胞的表面触发炎症介质的释放,有助于广泛的临床表现,包括全身过敏反应.肥大细胞在对食物的适应性免疫中也起着至关重要的作用,作为食物抗原驱动的Th2细胞反应的佐剂。虽然近年来食物过敏的诊断和治疗有所改善,目前尚无治愈性治疗方法。然而,有新的证据表明,过敏原特异性IgA和IgG抗体均可对抗IgE抗体对肥大细胞的激活作用.最值得注意的是,抗原特异性IgA和IgG抗体均在口服免疫治疗过程中诱导.在这次审查中,我们强调肥大细胞在食物过敏中的作用,既可作为即时超敏反应的诱导剂,也可作为2型适应性免疫反应的佐剂。此外,我们总结了目前对抗原特异性IgA和IgG抗体对IgE诱导的肥大细胞活化和效应功能的免疫调节作用的理解。对IgA和IgG在食物过敏中的调节作用的更全面了解可能提供对摄入抗原的免疫反应的生理调节的见解,并可能为治疗过敏性疾病提供新的策略。