Fibrinmonomer binding to macrophages mediated by fibrin-binding fibronectin fragments.
Binding of 125-I-fibrinmonomer to peritoneal macrophages was investigated in dependence of plasma fibronectin and of its thrombin- or plasmin-derived fragments. Plasma fibronectin failed to enhance cell binding of 125-I-fibrinmonomer. In contrast, 30kD-fragments derived from the N-termini of the fibronectin subunits improved binding considerably. The association with the cell surface was completely inhibited by EDTA, 2-5 mM putrescine and to about 40 per cent by 0.1 mM dansylcadaverine suggesting that a transamidase-catalyzed cross-linking reaction was involved. Thrombin-derived 200kD-remnants of the fibronectin subunit chains failed to mediate cell binding of 125-I-fibrinmonomer provided they had been deprived of residual thrombin activity. Otherwise they were active and their activity was inhibited by the thrombin inhibitor hirudin. Plasmin-derived 200 kD-fragments were inactive as well.
D000818:Animals; D001665:Binding Sites; D002103:Cadaverine / Q000031:analogs & derivatives / Q000494:pharmacology; D004492:Edetic Acid / Q000494:pharmacology; D005337:Fibrin / Q000378:metabolism*; D005353:Fibronectins / Q000378:metabolism*; D006168:Guinea Pigs; D006629:Hirudins / Q000378:metabolism; D006801:Humans; D008264:Macrophages / Q000378:metabolism*; D010446:Peptide Fragments / Q000378:metabolism; D011485:Protein Binding / Q000187:drug effects; D011700:Putrescine / Q000494:pharmacology
D005353:Fibronectins; D006629:Hirudins; D010446:Peptide Fragments; D005337:Fibrin; D004492:Edetic Acid; C008542:monodansylcadaverine; D002103:Cadaverine; D011700:Putrescine