Recombinant Human Low affinity immunoglobulin gamma Fc region receptor II-b (FCGR2B), partial

Function

Receptor for the Fc region of complexed or aggregated immunoglobulins gamma. Low affinity receptor. Involved in a variety of effector and regulatory functions such as phagocytosis of immune complexes and modulation of antibody production by B-cells. Binding to this receptor results in down-modulation of previous state of cell activation triggered via antigen receptors on B-cells (BCR), T-cells (TCR) or via another Fc receptor. Isoform IIB1 fails to mediate endocytosis or phagocytosis. Isoform IIB2 does not trigger phagocytosis

Subcellular Location

Cell membrane (Single-pass type I membrane protein)

Disease Association

Systemic lupus erythematosus (SLE) : A chronic, relapsing, inflammatory, and often febrile multisystemic disorder of connective tissue, characterized principally by involvement of the skin, joints, kidneys and serosal membranes. It is of unknown etiology, but is thought to represent a failure of the regulatory mechanisms of the autoimmune system. The disease is marked by a wide range of system dysfunctions, an elevated erythrocyte sedimentation rate, and the formation of LE cells in the blood or bone marrow. [Disease susceptibility is associated with variants affecting the gene represented in this entry]

Tissue Specificity

Is the most broadly distributed Fc-gamma-receptor. Expressed in monocyte, neutrophils, macrophages, basophils, eosinophils, Langerhans cells, B-cells, platelets cells and placenta (endothelial cells). Not detected in natural killer cells

Subunit

(Microbial infection) Isoform IIB1 interacts with measles virus protein N. Protein N is released in the blood following lysis of measles infected cells. This interaction presumably block inflammatory immune response

• Ng S. et al. Fc-gamma-RIIb nucleotide sequences in SLE and non-SLE humans in vivo derived lymphocytes. (JAN-)
• Stuart S.G. et al. Human IgG Fc receptor (hFcRII; CD32) exists as multiple isoforms in macrophages, lymphocytes and IgG-transporting placental epithelium. — EMBO J. (1989)
• Brooks D.G. et al. Structure and expression of human IgG FcRII(CD32). Functional heterogeneity is encoded by the alternatively spliced products of multiple genes. — J. Exp. Med. (1989)
• Engelhardt W. et al. Distribution, inducibility and biological function of the cloned and expressed human beta Fc receptor II. — Eur. J. Immunol. (1990)
• Ebert L. et al. Cloning of human full open reading frames in Gateway(TM) system entry vector (pDONR201). (MAY-)
• Gregory S.G. et al. The DNA sequence and biological annotation of human chromosome 1. — Nature (2006)
• The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC). — Genome Res. (2004)
• Kyogoku C. et al. Fc gamma receptor gene polymorphisms in Japanese patients with systemic lupus erythematosus: contribution of FCGR2B to genetic susceptibility. — Arthritis Rheum. (2002)