FcγRIIB: a modulator of cell activation and humoral tolerance.

Institute of Genetics, Department of Biology, University of Erlangen Nürnberg, Staudtstr. 5, 91058 Erlangen, Germany.
Expert Review of Clinical Immunology (Impact Factor: 3.34). 03/2012; 8(3):243-54. DOI: 10.1586/eci.12.5
Source: PubMed

ABSTRACT An immune response needs to be tightly regulated to prevent excessive inflammation, which may result in the destruction of healthy tissues. At the molecular level, the strength of an immune response is determined by the integration of a multitude of positive and negative signals. This review will focus on IgG-dependent immune responses and discuss how the inhibitory receptor FcγRIIB may be involved in regulating both the afferent and efferent phases of such a response. Furthermore, we will discuss recent evidence suggesting that FcγRIIB may have important functions beyond the negative regulation of signals transduced by the B-cell receptor or activating FcγRs and could be responsible for the activity of agonistic antibodies in vivo.

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