The formation of a fibrin clot is initiated after the proteolytic cleavage of fibrinogen by thrombin. The enzyme removes fibrinopeptides A and B and generates fibrin monomer which spontaneously polymerizes. Polymerization appears to occur though the interaction of complementary binding sites on the NH2-terminal and COOH-terminal (Fragment D) regions of the molecule. A peptide has been isolated ...

A series of small peptides corresponding to the amino termini of the fibrin alpha- and beta-chains has been synthesized. The peptides glycyl-L-prolyl-L-arginyl-L-proline and glycyl-L-prolyl-L-arginylsarcosine are potent inhibitors of fibrin polymerization. Moreover, these peptides have a natural stability stemming from their inherent resistance to proteolysis because of the involvement of amino...

1. The factor XIII-mediated cross-linked alpha chains in fibrin have no effect on the nature of the fragments released during the solubilization of fibrin by plasmin. 2. Besides the known D dimer and E fragments solubilized during the lysis of cross-linked fibrin, other fragments have been observed on sodium dodecyl sulphate-polyacrylamide gel electrophoresis which have a molecular weight of ab...

Increased concentrations of plasmin-catalyzed degradation products of fibrin and fibrinogen in body fluids have been correlated with many disease states. We have developed monoclonal antibodies that react with one of these products, fragment D. Antibodies binding fragment D but not fibrinogen were found to have low affinity constants (Ka = 10(7) L/mol). A double monoclonal-antibody assay was de...

Specific plasminogen-binding sites of fibrin molecule are located in Аα148-160 regions of C-terminal domains. Plasminogen interaction with these sites initiates the activation process of proenzyme and subsequent fibrin lysis. In this study we investigated the binding of plasminogen fragments K 1-3 and K 5 with fibrin fragment DD and their effect on Glu-plasminogen interaction with DD. It was sh...

When granulocytes are stimulated under certain clinical conditions, elastase is released therefrom and digests fibrin(ogen) independently of the plasmin system, which may also be mobilized simultaneously. Thus, discrimination of these 2 systems becomes urgent for the diagnosis and treatment of the underlying diseases. Using as immunogen a 97-kd granulocyte-elastase digest of human fibrinogen, w...

Following proteolytic conversion of fibrinogen to fibrin, clot assembly commences with formation of double-stranded fibrils that subsequently branch extensively in forming a three-dimensional network. Plasmin digests of fibrin clots that had first been covalently crosslinked by plasma transglutaminase (factor XIIIa) contained multimeric proteolytic fragments composed of crosslinked outer (D) do...

Although abnormalities in coagulation tests have been reported during vaso-occlusive crises in patients with sickle cell disease, objective, readily performed laboratory tests that document the occurrence of this complication have not been available. We examined the relationship between fibrin D-dimer levels and the occurrence of complications in patients with sickle cell disease, using a comme...

Fibrin has recently been shown to activate platelets through the immunoglobulin receptor glycoprotein VI (GPVI). In the present study, we show that spreading of human platelets on fibrin is abolished in patients deficient in GPVI, confirming that fibrin activates human platelets through the immunoglobulin receptor. Using a series of proteolytic fragments, we show that D-dimer, but not the E fra...

background: endometriosis is the presence of endometrial tissue outside of the uterine cavity and is the most common gynecologic disorder in women of reproductive age. we have preliminary evidence that in the presence of a 3-dimensional (3-d) fibrin matrix, human endometrial glands, stroma, and neovascularization can develop in vitro, mimicking the earliest stages of endometriosis. the aim of t...