CD23, also known as Fc epsilon RII, or FcεRII, is the "low-affinity" receptor for IgE, an antibody isotype involved in allergy and resistance to parasites, and is important in regulation of IgE levels.

This review summarizes recent data on CD23, a low affinity receptor for IgE (Fc epsilon RII). CD23 is the only FcR which does not belong to the immunoglobulin gene superfamily.

May 16, 2016 · We examined the expression of CD23 in different subsets of peripheral B cells and the impact of CD23 expression on the early events of B-cell receptor (BCR) activation using CD23 knockout...

While evidence from experimental disease models as well as allergic patient studies on CD23 is still lacking, evidence shows that i) CD23 can absorb and clear IgE from the serum in a non‐inflammatory fashion, ii) CD23 reduces the synthesis of IgE from B cells, iii) CD23 regulates antigen‐specific IgG and T cell responses.

The lower-affinity IgE Fc receptor, CD23, has multiple functions in enhancing the ... The association of immunoglobulin E (IgE) with allergic diseases and asthma is well established. IgE binds to two receptors on various immune and inflammatory cells.

39.5.2.2 CD23 (FcεRII): The Low-affinity Receptor for IgE. CD23 is a type II integral membrane protein with an extracellular C-terminal domain that is homologous to C-type lectins.

The structure of CD23 and the trimer model, the location of its binding sites for IgE and CD21, and the clustering of CD23 caused by IgE Fc lend support to this mechanism and suggest strategies for down-regulation of IgE levels to treat allergic disease.