FcRn (E6D1S) Rabbit Monoclonal Antibody #88175

The neonatal Fc receptor, FcRn, is an atypical Fc gamma receptor that bears homology to class I MHC (major histocompatibility complex) and associates with β2-microglobulin (1). FcRn is expressed by the vascular endothelium, several epithelial cell types, and hematopoietic cells including several innate immune cell types and B cells (2). FcRn mediates recycling and transcytosis of IgG, resulting in protection of IgG from catabolism and an extended serum half-life of IgG relative to other antibody isotypes (3). In addition, FcRn transports IgG across the placenta and also mediates uptake of maternal IgG from milk, resulting in enhanced humoral immunity in the fetus and neonates (1,4,5). FcRn also plays an important role in initiation of adaptive immunity by transporting immune complexes to intracellular dendritic cell compartments for antigen processing and presentation to T cells (6-8). In addition to IgG, FcRn also binds albumin and similarly protects it from catabolism, leading to extended half-life and high plasma concentrations (9).