Factor XII (F.XII, also called Hageman Factor) is a glycoprotein that circulates at levels of 40ug/ml in plasma. Activation of F.XII occurs as a consequence of binding to a negatively charged surface or from the proteolysis by kallikrein to produce alphaXIIa which in turn canactivate F.XI to F.XIa. alpha-XIIa can be further cleaved by kallikrein to form alphaXIIa which can feed back to activate more prekallikrein to kallikrein and can also activate F.VII and the classical complement pathway. The natural inhibitors of F.XIIa in plasma are, in order of importance, C1-Inhibitor, alpha 2 Antiplasmin and alpha 2 Macroglobulin.
F.XII in plasma and other fluids can be measured by sandwich-style immunoassay. The F.XII is captured onto a microtiter plate coated with affinity purified goat anti-F.XII. The plate is washed to remove unbound protein and the the captured F.XII is then detected with the addition of goat anti-F.XII IgG conjugated to HRP. The plate is again washed and bound antibody conjugate activity is expressed by incubation with substrate, ortho-phenylene diamine (OPD) for a limited time. The color generated is proportional to the concentration of F.XII initially present in the sample.
Materials Supplied:Antibodies for 5x96 well plates
Kit Components:F0019-08A: Capture Antibody 1x500ul Purified by immunoaffinity chromatography. Supplied a liquid in 50% glycerol. For coating ELISA plates
F0019-08B: Detecting Antibody (HRP) 1x500ul Purified by immunoaffinity chromatography. Supplied a liquid in 50% glycerol. For detection of captured F.XII.
Storage and Stability:May be stored at 4°C for short-term only. Aliquot to avoid repeated freezing and thawing. Store at -20°C. Aliquots are stable for 12 months after receipt. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.
