APCS (amyloid P component, serum), also known as pentraxin 2 (PTX2), is a member of the pentraxin family, which has a characteristic non-covalently linked pentameric organization. This protein is characterized by its calcium-dependent ligand binding and distinctive flattened β-jellyroll structure similar to legume lectins. Human APCS shares a 79% amino acid homology with its mouse counterpart. APCS is secreted by hepatocytes as part of the acute phase protein synthesys in response to infections. Upon binding to its ligands, APCS is involved in the activation of classical complement cascade. In a mouse model, APCS was shown to downregulate acute inflammation accompanying experimental autoimmune encephalomyelitis by regulating T cell activity. Besides its role in regulating immune response, APCS is found to be a component of amyloid deposits, which has the ability of stabilizing amyloid fibrils and protecting them from proteolytic degradation. Based on these studies, it was postulated that APCS may play a role in Alzheimer's disease and other amyloidoses. Interestingly, APCS is also identified as a component of basement membrane proteins, and is able to bind laminin, collagen IV, P-selectin, and fibronectin in a Ca2+ dependent manner. In addition, APCS is known to specifically localize in human atherosclerotic lesions, which suggests that it may play a role in atherogenesis. Functional studies revealed that APCS binds to lipoproteins, specifically to HDL, but not LDL.
Size
100 μg
Concentration
n/a
Applications
BA
Other Names
Amyloid P component serum, Serum Amyloid P (SAP), Pentraxin 2 (PTX2), HEL-S-92n