Factor XII polyclonal, anti-human

Quantity: 200 µl

Background:
The defined antibody reactivity is restricted to FXII, FXIIa and complexes of FXIIa with other proteins. In immunoelectrophoresis, bi-dimensional electrophoresis and radial immunodiffusion (Ouchterlony) against normal plasma, a single precipitin line is obtained which shows a reaction of identity with precipitated purified Factor XII. No reaction is obtained with FXII-depleted plasma. This antiserum is primarily intended for the measurement of Factor XII in human plasma using the EIDmethod (Laurell): a specially purified agarose (Agarose Nordic Nr. 4) solution containing between 1 and 2% antiserum is poured onto a glass plate and allowed to gel. Plasma containing FXII is incorporated into a series of wells and electrophoresis is performed. Rockets due to antigen/antibody reaction are measured. The height of the rocket is directly proportional to the FXII concentration in the plasma. The concentration of FXII in normal adult plasma is about 40 ?g/ml. Newborn infants have moderately lower levels. Plasma level fall moderately during pregnancy. Congenital and acquired deficiencies are known. Homozygotes have a thrombotic tendency. They usually have reduced FXII antigen and FXII coagulant activity but rare cases have normal FXII antigen levels. Acquired reduction in antigen level and clotting activity have been described in disseminated intravascular coagulopathy, in cirrhosis, but not in chronic active hepatitis and in nephrosis. A marked increase of the plasma level may occur due to oestrogen action during oral contraception. Circulating antibodies against FXII have rarely been observed but are associated with a bleeding tendency.

Isotype: Goat Polyclonal

Source: Factor XII (Hageman factor) is a single chain glycoprotein (MW 80,000). It is a serine protease zymogen. FXII is converted to an active enzyme by damage to vascular endothelium. In vitro activation is caused by glass or kaolin. Surface binding promotes activation by kallikrein. FXIIa activates prekallikrein and FXI. Kallikrein activates more FXII. Fragments of FXIIa activate FVII to FVIIa, and plasminogen to plasmin. The complement system is also activated by FXIIa. A link between fibrin clot and the subendothelium is formed by FXIIa crosslinking with fibrin, alpha-2 plasmin inhibitor, fibronectin and Van Willebrand factor. Purified plasma FXII is used as immunogen.Freund's complete adjuvant is used in the first step of the immunization procedure.

Form: Delipidated, heat inactivated, in PBS and 0.1% sodium azide.

Specificity:
Precipitating polyclonal Goat anti-Serum to Human coagulation Factor XII

Reactivity: human

Cross Reactivity:
The antiserum does not cross-react with any other Human plasma proteins as tested in gel-diffusion techniques. Inter-species cross-reactivity is a normal feature of antibodies to plasma proteins, since homologous proteins of different species frequently share antigenic determinants. Cross-reactivity of this antiserum has not been tested in detail, however in immunoelectrophoresis a reaction with Rhesus Monkey plasma has been found.

Applications: Immunoprecipitation

Storage: Store at 4C, or in small aliquots at -20C.