Factor XII Polyclonal Antibody – Affinity Purified
Affinity’s Factor XII Polyclonal Antibody – Affinity Purified is the highest level of our Factor XII antibody family. During the Antigen Affinity Purification process the IgG has had any non-specific immunoglobulin fraction eliminated which enriches the specificity of the remaining immunoglobulin towards the target antigen. The result is a very high-purity product with a substantially higher titre than whole or purified IgG. Our Factor XII Polyclonal Antibody – Affinity Purified is provided in a solution of HEPES buffered saline containing 50% glycerol (v/v) and is intended for applications such as immunoblotting, immunostaining of cells and several types of immunoassays where the higher signal-to-noise ratio achieved with this enriched product is required.
Product Code: GAFXII-AP
Retail Product Size: 0.5mg vial
Host Animal: Goat Anti-Human Factor XII Polyclonal Antibody – Affinity Purified
Species Cross Reactivity: View Chart
Product Datasheet: Factor XII F12 Polyclonal Antibody, affinity purified anti-human goat IgG
Description of Factor XII (FXII)
Factor XII (FXII, Hageman factor) is a 76 kDa, single chain glycoprotein produced in the liver. In plasma, FXII circulates as a protease zymogen at a concentration of approximately 30 μg/ml (400 nM). Upon vascular injury FXII binds to negatively charged extravascular surfaces such as cartilage and skin, which facilitate activation of the zymogen to the active serine protease. Cleavage of F.XII by kallikrein after residue Arg353 produces the enzyme αFXIIa, consisting of a 28 kDa light chain containing the protease domain, and a 52 kDa heavy chain containing the anionic surface-binding domain. Substrates for surface bound FXIIa include the zymogens prekallikrein (PK) and factor XI (FXI) as well as the procofactor high-molecular weight kininogen (HK). The activation of these substrates results in positive feedback activation of FXII. Further cleavage of αFXIIa by kallikrein produces the 28 kDa fragment βFXIIa (Hageman factor fragment). βFXIIa has reduced procoagulant activity as it lacks the anionic surface-binding domain, but is capable of fluid-phase activation of PK, factor VII and complement C1. The activity of F.XIIa in plasma is regulated predominantly by C1-Inhibitor, with relatively minor contributions by alpha-2-antiplasmin, alpha-2-macroglobulin and antithrombin, even in the presence of therapeutic levels of heparin1-3.
References and Review
- DeLa Cadena R, Watchtfogel YT, Colman RW, in Hemostasis and Thrombosis, 3rd Edition, eds. RW Colman, J Hirsh, VJ Marder and EW Salzman, pp. 219-240, J.B. Lippincott Co., Philadelphia, 1994.
- Tankersley DL, Alving BM, Finlayson JS; Preparation of βF.XIIa (Hageman Factor Fragment) from Human Plasma. Thrombosis Research 25 pp 307-317, 1982.
- Pixley RA, Schapira M, Coleman RW; The regulation of Human Factor XIIa by Plasma Proteinase Inhibitors. JBC 260, pp 1723-1729, 1985.