Factor VII Inhibitor Plasma
Factor VII Inhibitor Plasma is manufactured from normal citrated human plasma depleted of Factor VII using antibodies directed to FVII immobilized on agarose beads. A polyclonal antibody inhibitory to FVII has been added to provide FVII neutralizing activity. The neutralizing antibody activity is determined by Nijmegen-modified Bethesda Inhibitor Assay and has values reported in Bethesda Units. Our Factor VII Inhibitor Plasma is produced with three levels of inhibitor titre or neutralizing activity ranging from:
Mild Factor VII Inhibitor (1-10 BU/mL)
Moderate Factor VII Inhibitor (>10-50 BU/mL)
Strong Factor VII Inhibitor (>50-200 BU/mL)
Frozen or Lyophilized formats available
Only the highest quality citrated plasma is used as starting material and in many cases the parent plasma is available as control material. Our Factor VII Inhibitor Plasma can be used for further manufacturing or research use only applications.
Frozen Factor VII Inhibitor Plasma
Product Code: INH7-DP
Presentation: Frozen Factor VII Inhibitor Plasma
Preparation/Handling: Thaw 1 ml vials in 37oC water bath for 5 minutes; for bulk volumes, thawing time will be dependent on bottle size.
Storage and Stability: Plasma is shipped frozen and should be stored below -60oC. Product is stable until date stated on vial label when stored at -60oC. Once thawed, plasma is stable for 4 hours at 2-8oC in original vial.
Certificate of Analysis: available upon request
Description of Factor VII
Factor VII (FVII, also known as Stable Factor and Proconvertin) is a vitamin K-dependent glycoprotein produced in the liver. Plasma concentration of FVII is normally ~0.5 μg/ml (10 nM) in plasma. A deficiency of FVII is associated with bleeding in a clinical pattern similar to haemophilia, but is inherited as an autosomal recessive trait. The deficiency can be characterized by a quantitative (low activity and low antigen) or a qualitative (low activity and normal antigen) defect in FVII function. In its zymogen form FVII is a single chain molecule of ~50 kDa. It contains two EGF-like domains and an amino-terminal domain containing 10 γ-carboxyglutamic acid (Gla) residues. These Gla residues allow FVII to bind divalent metal ions and participate in calcium-dependent binding interactions. FVII and activated FVII (FVIIa) bind to tissue factor exposed at the site of vascular injury. FIXa, FXa or FVIIa rapidly activate tissue factor-bound FVII to FVIIa in the presence of calcium and phospholipid. Thrombin and FXIIa are able to activate FVII in the fluid phase in the absence of cofactors. The activation of the single chain zymogen FVII occurs by proteolysis after residue Arg152, resulting in a two-chain active serine protease consisting of a 30 kDa heavy chain and a 18 kDa light chain. In complex with tissue factor, phospholipid and calcium, FVIIa is able to activate F.X and F.IX. Free FVIIa in plasma is remarkably stable, but the activity of FVIIa/TF complex is regulated by Tissue Factor Pathway Inhibitor (TFPI) in the presence of F.Xa, and also by Antithrombin (ATIII) in the presence of heparin1-3.
References and Reviews
- Rao LVM, Bajaj SP, Rapaport SI; Activation of Human Factor VII During Clotting in Vitro; Blood 65, pp 218-226, 1985.
- Lawson, JH, Butenas S, Ribarik N, Mann KG; Complex-dependent Inhibition of Factor VIIa by Antithrombin III and Heparin; JBC 268 pp 767-770, 1993.
- Nemerson Y, in Hemostasis and Thrombosis, 3rd Edition, eds. RW Colman, J Hirsh, VJ Marder and EW Salzman, pp. 81-93, J.B. Lippincott Co., Philadelphia PA, USA, 1994.