CD16
CD16 (FCGR3A, also known as CD16a, FcgammaRIIIa and FcGRIIIA) is a low affinity receptor for the Fc portion of immunoglobulin G. It helps clear antigen-antibody complexes from the circulation and mediates antibody-dependent cellular cytotoxicity. Browse Assay Genie's current range of CD16 research reagents below, or read on for the biology behind the target.
CD16 is a receptor for the Fc region of immunoglobulin G. It is involved in removing antigen-antibody complexes from the circulation and in other antibody-driven responses, including antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent enhancement (ADE) of virus infection. In the Dengue virus setting, secondary infection raises levels of afucosylated, non-neutralising IgG1 antibodies that react with the viral envelope protein. Complexes of viral antigen and IgG1 bind CD16 with high affinity, which promotes virus entry into myeloid cells and subsequent viral replication.
The FCGR3A gene encodes the Fc gamma receptor IIIa protein, which UniProt lists as low affinity immunoglobulin gamma Fc region receptor III-A. UniProt records both cell membrane and secreted forms. The receptor is expressed on natural killer (NK) cells as an integral membrane glycoprotein anchored through a transmembrane peptide. The CD16 gene is highly similar to a nearby gene on chromosome 1, FCGR3B. FCGR3B is expressed on polymorphonuclear neutrophils, where its receptor is anchored through a phosphatidylinositol linkage instead. Alternatively spliced transcript variants encoding different isoforms have been reported.
HGNC places the gene in the CD molecules, immunoglobulin-like domain containing and Fc receptors groups. Earlier names include Fc fragment of IgG, low affinity IIIa, receptor (CD16a), and the symbols FCGR3 and FCG3 have also been used. Mutations in the gene are associated with immunodeficiency 20. They have also been linked to susceptibility to recurrent viral infections, to systemic lupus erythematosus and to alloimmune neonatal neutropenia. The mouse ortholog is Fcgr4 and the rat ortholog is Fcgr3a.
CD16 is the IgG Fc receptor expressed on natural killer cells, making it central to studies of antibody-dependent cellular cytotoxicity.
The receptor contributes to removal of antigen-antibody complexes from the circulation, relevant to immune regulation and autoimmune mechanisms.
Binding of afucosylated IgG1-antigen complexes to CD16 supports Dengue virus entry into myeloid cells, a model of antibody-dependent enhancement.
Variants in the gene are linked to immunodeficiency 20, recurrent viral infection, systemic lupus erythematosus and alloimmune neonatal neutropenia.
CD16 binds the Fc portion of IgG. It is involved in clearing antigen-antibody complexes from the circulation, in antibody-dependent cellular cytotoxicity and in antibody-dependent enhancement of virus infection. On NK cells it is an integral membrane glycoprotein anchored through a transmembrane peptide.
The two genes are highly similar and lie close together on chromosome 1. The FCGR3A receptor is expressed on NK cells and anchored by a transmembrane peptide. FCGR3B is expressed on neutrophils and anchored through a phosphatidylinositol linkage. Check the datasheet of any product for its validated reactivity.
Mutations in the CD16 gene are associated with immunodeficiency 20. They have also been linked to susceptibility to recurrent viral infections, systemic lupus erythematosus and alloimmune neonatal neutropenia. The receptor also contributes to Dengue virus pathogenesis through antibody-dependent enhancement. The mouse ortholog is Fcgr4.
Other Fc gamma receptors that bind immunoglobulin G and shape antibody-driven immune responses.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P08637; product specifications from Assay Genie datasheets.