VSIG4 (human):Fc (mouse) (rec.)

VSIG4 (V-set and immunoglobulin domain containing 4), as known as complement receptor of the immunoglobulin superfamily (CRIg) and Z39Ig. It is a B7 family-related protein and an Ig superfamily member. In contrast to the B7 family members which contain two IgG domains, VSIG4 contains one complete V-type I g domain and a truncated C-type I g domain. VSIG4 is exclusively expressed on tissue resident macrophages and binds to multimers of C3b and iC3b that are covalently attached to particle surfaces. VSIG4 functions as a negative regulator of T cell activation, and may be involved in the maintenance of peripheral T cell tolerance, and is also identified as a potent suppressor of established inflammation.