84-1052-87　Factor XII (Hageman Factor) 1mg　F0019-06A

特徴

• Factor XII (F.XII, Hageman factor) is a 76kD, single chain glycoprotein produced in the liver.
• In plasma, F.XII circulates as a protease zymogen at a concentration of~30ug/ml (400nM).
• Upon vascular injury F.XII binds to negatively charged extravascular surfaces such as cartilage and skin, which facilitate activation of the zymogen to the active serine protease.
• Cleavage of F.XII by kallikrein after residue Arg353 produces the enzyme alapha F.XIIa, consisting of a 28kD light chain containing the protease domain, and a 52kD heavy chain containing the anionic surface-binding domain.
• Substrates for surface bound F.XIIa include the zymogens prekallikrein (PK) and factor XI (F.XI) as well as the procofactor high-molecular weight kininogen (HK).
• The activation of these substrates results in positive feedback activation of F.XII.
• Further cleavage of alpha F.XIIa by kallikrein produces the 28kD fragment beta F.XIIa (hageman factor fragment).
• beta F.XIIa has reduced procoagulant activity as it lacks the anionic surface-binding domain, but is capable of fluid-phase activation of PK, factor VII and complement C1.
• The activity of F.XIIa in plasma is regulated predominantly by C1-Inhibitor, with relatively minor contributions by alpha 2antiplasmin, alpha 2macroglobulin and antithrombin, even in the presence of therapeutic levels of heparin.
• Applications:Suitable for use in ELISA and Immunoelectrophoresis.
• Other applications not tested.
• Recommended Dilutions:Optimal dilutions to be determined by the researcher.
• Extinction Coefficient:E1% 280 = 13.4
• 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.