Description
Factor XII Paired Antibody Set
Affinity’s Factor XII Paired Antibody Set consists of matched capture and detecting antibodies that have been titrated and optimized for use in sandwich style ELISA assays. The product as provided contains sufficient capture and detecting antibodies for five full 96-well microplates and contains a detailed protocol sheet containing directions for use, recipes for solutions and sources for additional materials required. This Factor XII Paired Antibody Set is intended to facilitate the end user in establishing an “in-house” immunoassay for research purposes only and must not be used for diagnostic applications. Assay validation is the responsibility of the end user.
Product Code: FXII-EIA
Supplied Materials:
- Capture Antibody (FXII-EIA-C): One yellow-capped vial containing 0.5 ml of polyclonal affinity purified anti-Factor XII antibody for coating plates.
- Detecting Antibody (FXII-EIA-D): One red-capped tube containing 0.5 ml of peroxidase conjugated affinity-purified polyclonal anti-Factor XII antibody for detection of captured Factor XII.
Related Products: VisuLize Buffer Pak Factor XII Deficient Plasma
Species Cross Reactivity: View Chart
Product Datasheet: Factor XII (F12) Antigen Matched Pair Antibody Set for ELISA - FXII-EIA
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 α2antiplasmin, α2macroglobulin and antithrombin, even in the presence of therapeutic levels of heparin1-3.
References and Reviews
- 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.