Fibrinogen electrophoresis

PLASMA. The portion of the blood remaining after removal of the white and red cells and the platelets it differs from serum in that it contains fibrinogen, which induces clotting by conversion into fibrin by activity of the enzyme thrombin. Plasma is made up of more than 40 proteins and also contains acids, lipids, and metal ions. It is an amber, opalescent solution in which the proteins are in colloidal suspension and the solutes (electrolytes and nonelectrolytes) are either emulsified or in true solution. The proteins can be separated from each other and from the other solutes by nltrafiltration, nltracentrifugation, electrophoresis, and immuno-chemical techniques. See also Blood. 

From a strict biochemical point of view a clear-cut definition of the role of the liver in the biosynthesis of any particular plasma protein can be made only when the particular protein has been clearly and cleanly isolated, as in the case of fibrinogen. The practical difficulties of effecting such isolations on a small scale from isotopic labeling studies of the plasma proteins, such as we have described, seriously militate against such a detailed demonstration at present. The use of fractionation techniques with greater resolving power such as acrylamide gel electrophoresis already show some promise in our laboratory toward affording a more definitive picture of the biosynthetic role of the liver and the nonhepatic tissues in plasma protein production. 

Abnormal narrow bands on electrophoresis which might falsely be called paraproteins are in serum (i) fibrinogen—a subsequent clot or... 

Heparinoids and mucopolysaccharides react with, and modify, many of the plasma proteins. Heparin combines with fibrinogen, globulins and albumin. As judged by electrophoresis and various types of analysis and staining, the particular plasma protein components with which heparin combines are dependent upon the concentration of protein, concentration of heparin, pH value, and salts present. This explains the somewhat contradictory statements in literature about combinations of heparin with plasma proteins. The combination may result in change of solubility of the protein and reverse protein tests . Heparin can modify the murexide reaction for calcium in serum by affecting the calcium-protein-heparin complex. Many heparinoids... 

Snellman, Sylven and Julen isolated the heparin polypeptide and showed that this material is a potent antithrombin on thrombin with purified fibrinogen, suggesting that heparin in the mast cells is in the active anticoagulant form. Electrophoresis shows that this native heparin forms a complex compound with thrombin and also with a lipoprotein molecule. They conclude the whole heparin complex is produced in the intergranular cytoplasm of the tissue mast cells. 

Because fibrinogen remains at the gel top in the electrophoresis system used here, we cannot assess its importance because staining artifacts frequently occur at the gel top. However, adsorption of 125I-fibrinogen to polyacrylamide-Silastic shunt surfaces from baboon blood in vivo is much greater than adsorption to Silastic shunt surfaces (46). 

Gel electrophoresis of SDS eluates from surfaces adsorbed at low concentrations revealed normal fibrinogen subunit distribution but additional altered forms were observed on surfaces adsorbed at high concentrations. 

Figure 5. SDS-polyaerylamide gel electrophoresis (reducing conditions) of fibrinogen after elution from glass bead column.

Vo, T. U., McGown, L. B. (2006). Effects of G-quartet DNA stationary phase destabilization on fibrinogen peptide resolution in capillary electrochromatography. Electrophoresis 27, 749-756. 

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