Product nameFactor VIIa Human Chromogenic Activity Assay Kit
Sample typeCell culture supernatant, Plasma
Assay typeEnzyme activity
Species reactivityReacts with: Human
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.
Storage instructionsStore at -20°C. Please refer to protocols.
Components 1 x 96 tests 10X Diluent M Concentrate 1 x 20ml 20X Wash Buffer Concentrate 1 x 30ml Assay Diluent 1 x 20ml Factor Xa Substrate 2 vials Human Factor VIIa Microplate 1 unit Human Factor VIIa Standard 1 vial Human Factor X 2 vials Sealing Tapes 3 units
FunctionInitiates the extrinsic pathway of blood coagulation. Serine protease that circulates in the blood in a zymogen form. Factor VII is converted to factor VIIa by factor Xa, factor XIIa, factor IXa, or thrombin by minor proteolysis. In the presence of tissue factor and calcium ions, factor VIIa then converts factor X to factor Xa by limited proteolysis. Factor VIIa will also convert factor IX to factor IXa in the presence of tissue factor and calcium.
Involvement in diseaseFactor VII deficiency (FA7D) [MIM:227500]: A hemorrhagic disease with variable presentation. The clinical picture can be very severe, with the early occurrence of intracerebral hemorrhages or repeated hemarthroses, or, in contrast, moderate with cutaneous-mucosal hemorrhages (epistaxis, menorrhagia) or hemorrhages provoked by a surgical intervention. Finally, numerous subjects are completely asymptomatic despite very low factor VII levels. Note=The disease is caused by mutations affecting the gene represented in this entry.
Sequence similaritiesBelongs to the peptidase S1 family.
Contains 2 EGF-like domains.
Contains 1 Gla (gamma-carboxy-glutamate) domain.
Contains 1 peptidase S1 domain.
modificationsThe vitamin K-dependent, enzymatic carboxylation of some glutamate residues allows the modified protein to bind calcium.
The iron and 2-oxoglutarate dependent 3-hydroxylation of aspartate and asparagine is (R) stereospecific within EGF domains.
O- and N-glycosylated. N-glycosylation at Asn-205 occurs cotranslationally and is mediated by STT3A-containing complexes, while glycosylation at Asn-382 is post-translational and is mediated STT3B-containing complexes before folding. O-fucosylated by POFUT1 on a conserved serine or threonine residue found in the consensus sequence C2-X(4,5)-[S/T]-C3 of EGF domains, where C2 and C3 are the second and third conserved cysteines.
- Information by UniProt
- Factor VII heavy chain
ab137995 has not yet been referenced specifically in any publications.