The reactivity of the antiserum is restricted to fibrinogen. In immunoelectrophoresis and radial mmunodiffusion (Ouchterlony), using various antiserum concentrations against fresh normal human plasma a single precipitin line is obtained which shows a reaction of identity with the precipitin line obtained with purified fibrinogen. No reaction is obtained with any other plasma protein component or serum. However, the antiserum may also react with fibrin monomers, circulating fibrinopeptides and fibrin degradation products. In precipitating techniques as immunoelectrophoresis and single or double radial immunodiffusion to identify the presence of fibrinogen in human plasma or other body fluids or to determine its concentration. The normal concentration of fibrinogen in the blood is 2.5 to 3.5 ml /ml, but lower levels are usually adequate for haemostasis. In newborn infants the value is 1.2 to 2.4 mg/ml. Synthesis of foetal fibrinogen may persists for up to 8 weeks, when adult levels are reached. Adult level increase with age and are a risk for heart disease, myocardial infarction and stroke. Fibrinogen is an acute Phase protein and increased levels are found in loosing enteropathies, in severe malnutrition, in tissue necrosis and in malignancy. Extremely high levels are seen in acute pancreatitis and, to a lower extent, in nephritic syndrome. A moderate raise may also been seen during pregnancy and the use of oral contraceptives. Fibrinogen deficiency may be congenital or acquired. If sufficiently severe, it may result in a bleeding disorder. The congenital form is very rare. Acquired hypofibrinogaemia is relatively common, probably indicating increased consumption during intravascular clotting.

Rabbit

Human

Precipitating polyclonal Rabbit antiSerum to Human fibrinogen.

Primary Antibodies

Immunoprecipitation

Immunology

Fibrinogen (clotting factor I) is a heat labile beta glycoprotein (molecular weight 340,000) and consists of three pairs of chains bound by disulphide bonds. It is synthesized in hepatocytes under genetic control. It is the precursor of fibrin, which is the key protein constituting the network of the blood clot. Thrombin converts fibrinogen to fibrin by limited proteolysis, releasing the fibrinopeptides A and B (molecular weight 50,000-65,000) and forming fibrin monomers. Fibrin monomers polymerize to fibrin which is stabilized by cross-linking under the influence of factor XIII. The predominant gamma chain of normal fibrinogen (MW 50,000, with higher variants) has a low affinity for platelet binding. Fibrinogen is isolated from fresh plasma after removing prothrombin. Freund

Delipidated, heat inactivated, lyophilized, stable whole antiserum No preservative added. Total protein and IgG concentrations in the antiserum are comparable to those of normal pooled rabbit serum. No foreign proteins added.

The antiSerum does not cross react with any other component of Human plasma. Inter-species crossreactivity is a normal feature of antibodies to plasma proteins since they frequently share antigenic determinants. Cross-reactivity of this antiSerum has not been tested in detail.

Lyophilized at +4