Description
Key facts
Detection method:Colorimetric,
Sample types:Plasma, Serum, Cell culture supernatant,
Reacts with:Human,
Assay type:Enzyme activity,
Sensitivity:= 6.9 ng/mL,
Assay Platform:Microplate reader
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.
Properties and Storage Information:
Shipped at conditions-Blue Ice, Appropriate short-term storage conditions--20°C, Appropriate long-term storage conditions-Multi, Storage information-Please refer to protocols
Supplementary Information:
This supplementary information is collated from multiple sources and compiled automatically.
Factor VIIa also known as activated Factor VII is a serine protease essential in the coagulation cascade. The protein has a molecular mass of around 50 kDa. Factor VIIa originates from its inactive precursor Factor VII primarily produced in the liver. Upon activation it becomes an important player in promoting blood coagulation. Factor VIIa's expression occurs mainly in the liver and circulates in the blood maintaining readiness for any vascular injury that may occur.
Biological function summary
Factor VIIa takes part in the initiation of the coagulation process. It does not function alone but combines with tissue factor (TF) to form the Factor VIIa-TF complex. This association triggers a domino effect that leads to blood clot formation by activating Factor IX and Factor X. The formation of this complex is the spark that ignites the coagulation cascade ensuring rapid response when vascular integrity is breached.
Pathways
This coagulation factor has a significant role in the extrinsic pathway of the blood coagulation process. It is intricately connected to other important proteins like prothrombin and thrombin through this pathway. Factor VIIa synergizes with tissue factor to kickstart the conversion of prothrombin to thrombin which further converts fibrinogen into fibrin solidifying the blood clot. Therefore Factor VIIa serves as a critical initiator within this pathway securing hemostasis.
Factor VIIa shows a strong connection to bleeding disorders and certain thrombotic conditions. Hemophilia patients often suffer from impaired activity in the coagulation cascade where deficiency in supporting proteins such as Factor IX or Factor VIII can be observed. Enhanced levels or malfunction of Factor VIIa can also contribute to thrombotic disorders where excessive or unregulated clotting occurs. Understanding the precise regulation of Factor VIIa Activity forms part of many therapeutic strategies targeting coagulation disturbances.
