Immunoglobulin E antibody and Antigen-presenting cell (IgE and APC)

IgE antibodies (Immunoglobulin E, IgE) are a class of immunoglobulin involved in type I hypersensitivity reactions such as allergies and anaphylaxis. IgE binds with high affinity to its primary receptor, FcεRI, on mast cells and basophils, and to a lesser degree to CD23 (FcεRII) on various antigen-presenting cells (APCs) such as dendritic cells, B cells, and macrophages. Cross-linking of cell surface-bound IgE by specific antigens leads to degranulation of mast cells and basophils, resulting in rapid release of inflammatory mediators. APCs, meanwhile, are a heterogeneous group of immune cells (not a single molecular entity) that specialize in capturing, processing, and presenting antigens to T cells, performing a crucial role in both the induction of IgE-mediated responses (via priming of Th2 cells and B cell class-switching) and the establishment of immune tolerance. IgE can also engage with APCs to enhance antigen uptake and cross-presentation, influencing adaptive immunity and potentially contributing to anti-tumor responses or amplified allergies. While IgE itself is a bona fide molecular target (notably by anti-IgE monoclonal antibodies like omalizumab), 'antigen-presenting cell' is a functional cell type, not a single molecular target, and should not be considered a discrete molecular drug target[2][4][5][6].

Other names

IgE (Immunoglobulin E)Antigen-presenting cell (APC)IgE antibodyAllergen-specific IgEDendritic cell (when referring to an APC subtype)Macrophage (when referring to an APC subtype)Monocyte (when referring to an APC subtype)FcεRI (high-affinity IgE receptor)CD23 (low-affinity IgE receptor)

IgE neutralization (prevents FcεRI/IgE binding) Blockade of mast cell/basophil degranulation Inhibition of cross-linking of IgE on effector cells Modulation of APC function (by immunomodulatory drugs)