Anti-Human gC1q-R Monoclonal Antibody (clone 74.5.2) -100 µg (CAT#: CB-P225-K) Datasheet

Antibody

Monoclonal antibody 74.5.2 recognizes a cell membrane C1q binding molecule that can recognize the spherical head of C1q. It is also present in plasma and extracellular matrix. This molecule is an abnormally acidic single-chain protein with an apparent molecular weight of 33. It has conventional sequence motifs compatible with the transmembrane segment and does not have a common site anchored by GPI; gC1q-R migrates as a single strand under reducing and non-reducing conditions, but it appears as oligomeric on the gel The formation of its polymer may be the key process for the gC1q-R molecule to increase its affinity with multivalent ligands (such as C1q).
It has been shown that gC1q-R can inhibit complement activation by preventing the binding of C1q to antibodies, which indicates that the binding site of gC1q-R and the binding site of immune complexes that may exist on the spherical "head" of C1q are at the same position. gC1q-R can interact with several proteins related to coagulation, namely thrombin, prothrombin, heparin-bound form of vitronectin, ternary complex, vitronectin-thrombin-antithrombin, and high molecular weight Kininogen and Hageman factor. In addition to its role in the complement pathway, gC1q-R is also involved in the enhancement of Fc receptor and CR1-mediated phagocytosis, the procoagulant activity of platelets, and the effect on mast cells, eosinophils, neutrophils and fibroblasts Chemotactic activity of cells.
gC1q-R is expressed in a variety of cells and can be used as a binding site for plasma and microbial proteins. Its antigenic sites may be recessive in suspension cells, but are exposed when the cells are fixed by a bifunctional crosslinker. Perhaps it is also expressed on the cell membrane as a tetramer. Therefore, cross-linking or activation can cause the assembly of the tetramer of gClq-R, and then a conformational change occurs in the molecule, thereby exposing the originally hidden epitope. A form of gC1q-R was also found in the cell. It has been shown that intracellular gC1q-R binds to the cytoplasmic tail of α1B-adrenergic receptor and binds to PKCμ.
Monoclonal antibody 74.5.2 is directed against the epitope in the XC15 peptide, which contains the binding sites for high molecular weight kininogen and factor XII. Clone 74.5.2 can recognize mature (74-282) and truncated forms, without residues 74-95. "