[Fibrin fragment beta 15-118. Inhibitory and complex-forming properties].

Peptide beta 15-118 isolated from desAABB-NDSK preserves fibrin polymerization active site "B", inhibits polymerization process at 12 degrees C, eliminates the inhibitory properties of plasmin D-D-fragment but does not influence inhibitory properties of a D-monomer fragment. Complex formation between peptide beta 15-118 and both D- and D-D fragments was electrophoretically demonstrated. Peptide beta 15-118 forms more stable complex with the D-D fragment which does not dissociate in the medium of polymerizing fibrin as the complex of the peptide with monomer D fragment does.

[Study of the polymerization of fibrin using monoclonal antibodies 2D-2A and their Fab-fragments].

It has been shown that monAb's 2d-2a and their Fab-fragments are specific and effective inhibitors of fibrinogen clotting. Only one IgG molecule of monAb's 2d-2a can bind with one of their epitopes situated around peptide bond B beta Arg14-Gly15 in dimer fibrinogen molecule reducing the rate of protofibril lateral association and clot turbidity with only one fibrinopeptide B splitting off per fibrinogen molecule by thrombin. But two molecules of Fab-fragments of monAb's 2d-2a join to both of their epitopes and inhibit fibrinogen clotting dramatically without clot formation and with no fibrinopeptide B splitting off.

[Structural organization of the monofilamentary protofibrils and their association into fibrils].

Evidence of the fibrinogen molecule structure which is suggestive of an antiparallel arrangement of polymerization sites is summarized. A three-dimensional model of the structural organization of a monofilamentary protofibril is proposed. A possible role of the "A" and "a" polymerization centers in the lateral association of protofibrils is contemplated.

The study of fibrin polymerization with monoclonal antibodies.

Three kinds of monoclonal antibody (Mab) of different specificity have been obtained against the N-terminal disulphide knots of fibrinogen and fibrin. Their effects on different phases of fibrin polymerization have been studied. These antibodies were shown to be directed against different epitopes of the B beta(1-53) fragment of the fibrinogen molecule.