FcgR4/CD16-2 Protein, Mouse (HEK293, His)

The FcγR4/CD16-2 Protein serves as a receptor for the constant Fc fragment of immunoglobulin gamma (IgG), exhibiting intermediate affinity for both IgG2a and IgG2b. It recognizes neutralizing virus-specific IgGs on infected cells, triggering antibody-dependent cellular cytotoxicity (ADCC) and conferring protection against lethal influenza virus infection. On splenic dendritic cells, FcγR4 efficiently uptakes antigen immune complexes, directing them into MHC class I and II antigen presentation pathways, thereby enhancing CD4-positive and CD8-positive T cell immune responses. Additionally, FcγR4 plays a crucial role in mediating neutrophil activation by IgG complexes, acting redundantly with FCGR2A. It contributes to bone resorption by enhancing osteoclast differentiation upon binding to IgG2a. Furthermore, FcγR4 functions as a receptor for the Fc region of immunoglobulin epsilon (IgE), binding to both a and b allotypes of IgE and promoting macrophage-mediated phagocytosis, antigen presentation to T cells, and the late phase of cutaneous allergic reactions. It forms a heterooligomeric complex with ITAM-containing signaling subunits FCER1G and interacts with the Fc region of antigen-complexed IgG.