Factor VIIa Human Chromogenic Activity Assay Kit

Product details

Abcam's Factor VIIa Human Chromogenic Activity Assay Kit (ab137995) is developed to determine Human Factor VIIa activity in plasma and cell culture supernatants. The assay couples immunofunctional and indirect amidolytic assay. A polyclonal antibody specific for Human Factor VIIa has been pre-coated onto a microplate and Factor VIIa is bound to the immobilized antibody. The assay measures the ability of Factor VIIa to activate factor X (FX) to factor Xa. The amidolytic activity of the Factor VIIa is quantitated by the amount of FXa produced using a highly specific FXa substrate releasing a yellow para-nitroaniline (pNA) chromophore. The change in absorbance of the pNA at 405 nm is directly proportional to the Factor VIIa enzymatic activity.

Factor VIIa assay protocol summary:
- add samples and standards to wells and incubate for 12 hrs
- wash 5x
- add assay mix and factor Xa substrate
- analyze with microplate reader, incubate for 20 hrs and then analyze every hour for further 8 hrs

The entire kit may be stored at -20°C for long term storage before reconstitution - Avoid repeated freeze-thaw cycles.

Factor VII (FVII) is a vitamin K-dependent plasma glycoprotein that is synthesized in the liver and circulates in blood as single-chain inactive zymogen with a MW=50kDa. Upon tissue damage and vascular injury, the cell surface receptor and cofactor tissue factor (TF) binds and allosterically activates FVII to its active form, FVIIa. The TF/FVIIa complex catalyzes the conversion of both factor IX to factor IXa and factor X to factor Xa to initiate coagulation via the extrinsic pathway.

Very low levels of FVII are associated with severe coagulation disorders, while elevated plasma levels of FVII coagulant activity constitute an indepent risk factor for fatal outcomes of coronary heart disease in middle-aged men.