IgE高亲合力受体的研究进展

Progress in the research of high affinity IgE receptor

IgE Fc段高亲和力受体(FcεRⅠ)在变态反应性疾病中起重要作用。典型的FcεRⅠ是αβγ2异四聚体复合物,表达在超敏反应效应细胞(即肥大细胞和嗜碱性粒细胞)膜表面。IgE与FcεRⅠ结合,导致肥大细胞和嗜碱粒细胞激活,并释放和合成各种炎症性介质和细胞因子等。IgE高亲和力受体也表达于嗜酸粒细胞和抗原提呈细胞(APC)如单核细胞、郎格汉斯细胞和树突状细胞表面。表达在抗原提呈细胞表面的FcεRⅠ是αγ2三聚体形式,它不能引起细胞脱颗粒,但可诱导炎症性细胞因子基因表达,并以IgE依赖性方式放大APC的抗原提呈效应。本文对FcεRⅠ的研究进展进行综述。

The FcεR Ⅰ, a high affinity receptor for immunoglobulin E (IgE), plays a pivotal role in the pathogenesis of allergic diseases. The classic FceR Ⅰ expressed on the effector cells of anaphylaxis (i.e., mast cells and basophils) is a tetrameric (αβγ2) molecule. The binding of IgE and FceR Ⅰ lead to the activating of mast cells and basophils, which then release an array of inflammatory mediators and cyto-kines. FcεRⅠ is also expressed on eosinophils and antigen-presenting cells (APCs) including monocytes, langerhans cells. and dendritic cells, The FceRⅠ expresed on APCs possess an unique trimeric (αγ2) structure, which can induce the expression of inflammatory cytokine gene, but not the cell-degranulation. Thus, FcεR Ⅰ on APCs acts as an allergen-focusing structure and can efficiently amplify allergen presentation ability of these cells in an IgE-dependent manner.