Human Factor Xa (FXa) RVV-X Activated

The lyophilized presentation allows greater stability until the expiration date.

Factor X is a vitamin K dependant, two-chain glycoprotein zymogen (Mr = 59 000) synthesized in the liver that circulates in plasma at a concentration of approximately 10 μg/mL.

Activation to factor Xa occurs by interaction with the intrinsic factor Xase complex (factor VIIa / IXa / Ca2+ / phospholipid) or the extrinsic factor Xase complex (Factor VIIa/tissue factor/Ca2+/phospholipid). Both complexes cleave the molecule at Arg52-Ile53, release an activation peptide from the heavy chain, resulting in factor Xa as a two-chain molecule where the light chain remains with a Mr of 17 000 and the heavy chain has been reduced to a Mr of 29 000.

Factor Xa provides the enzymatic activity of the prothrombinase complex (factor Xa / Factor Va / Ca2+ / phospholipid) which converts prothrombin to thrombin. While FXa can convert prothrombin to thrombin alone, its activity is greatly enhanced when a part of the complex. Its activity may be inhibited by inactivation of the factor Va cofactor or directly by a natural inhibitor such as antithrombin III (ATIII).