Molecular basis for measurement of circulating fibrinogen derivatives.
Fibrinogen plays a pivotal role in both the humoral and cellular mechanisms involved in hemostasis. In performing its hemostatic function, fibrinogen in turn is acted on by several independent enzyme systems that either modify its structure or cleave specific fragments of the molecule into the surrounding milieu. Measurements of enzymatically modified fibrinogen or its proteolysis products represent a means whereby the action of these specific enzymes can be quantitated both in vitro and in vivo. Advances in such techniques as protein purification, affinity chromatography, peptide synthesis, and radioimmunoassay technology permit the translation of recently acquired primary structural data on this important protein into sensitive and specific assays for its circulating derivatives. These assay systems are important tools for probing mechanisms of hemostasis and thrombosis.