FcER2

FcER2, also known as CD23, is a type II transmembrane protein that functions as a low-affinity receptor for immunoglobulin E (IgE). It is primarily expressed on B lymphocytes, eosinophils, basophils, mast cells, and dendritic cells. FcER2 plays a crucial role in the regulation of IgE production and is involved in B cell activation, proliferation, and differentiation. It exists in two isoforms, FcER2-a and FcER2-b, which are generated by alternative splicing and have distinct functional properties. The soluble form of FcER2, cleaved from the cell surface, can also exert regulatory effects. FcER2 is implicated in allergic responses, parasitic infections, and immune homeostasis. Its expression is upregulated by interleukin-4 (IL-4) and downregulated by interferon-gamma (IFN-γ). Dysregulation of FcER2 has been associated with various immune-mediated diseases. Research continues to explore its precise mechanisms of action and therapeutic potential.