Description
Binds to the Fc region of monomeric immunoglobulins gamma (PubMed:7964511, PubMed:10933786). Mediates the selective uptake of IgG from milk and helps newborn animals to acquire passive immunity. IgG in the milk is bound at the apical surface of the intestinal epithelium. The resultant FcRn-IgG complexes are transcytosed across the intestinal epithelium and IgG is released from FcRn into blood or tissue fluids (By similarity). Possible role in transfer of immunoglobulin G from mother to fetus (PubMed:7964511)