Factor XI polyclonal, anti-human

Quantity: 200 µl

Background:
The defined antibody reactivity is restricted to FXI, FXIa and complexes of FXI with HMWK or 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 XI. No reaction is obtained with FXI-depleted plasma. This antiserum is primarily intended for the measurement of Factor XI in human plasma using the EIDmethod (Laurell). FXI is one of the four proteins known to be involved in normal contact activation reactions, activating FXII to FXIIa, which is further capable of triggering the kinin-forming pathway and the fibrinolytic system.FXI is present in normal human plasma both in free form and as a reversible complex with HMWK. FXI competes with prekallikrein (PKK) to form such complexes. Since FXI is a gammaglobulin with cathodic mobility in electrophoresis, up to 140 ?g/ml purified HMWK must be added to the plasma to bind all free FXI into negatively charged complexes which will migrate to the anode. The total FXI content can then be measured. The average amount of FXI in an individual plasma was found to be 4.5 ?g/ml with a range of 3 to 6 ?g/ml. The sensitivity of the EIID method is about 0.2 ?g/ml. A congenital deficiency of FXI in plasma can give rise to a serious bleeding disorder. In most cases the plasma level of FXI antigen is also depressed; exceptionally the FXI antigen is normal ( a defective molecule) An acquired reduction in both clotting activity and FXI antigen level has been described in disseminated intravascular coagulopathy, in hepatic cirrhosis and in some patients with lupus erythomatosus.

Isotype: Goat Polyclonal

Source: Factor XI is a glycoprotein (MW 160,000) composed of two identical polypeptide chains. In electrophoresis it migrates in the gamma region. It is stable on storage, heat \stable at 56ﾺC for 30 minutes and not adsorbed by gels. Factor XI also occurs in platelets (MW 52,000). Factor XI is converted to an active enzyme by FXIIa but can be activated by other proteases such as trypsin. FXIa activates FIX, but can also activate FXII and plasminogen. Platelet membrane FXI can substitute for plasma FXI in coagulation. Plasma FXI is used for immunization.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 XI

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.

Applications: Immunoprecipitation

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