Tissue plasminogen activator in @entity1 XXXX and platelets: immunocytochemical localization, immunoblotting and zymographic analysis.

@entity1 @entity3479 @entity10706 @entity1351
Two approaches were used to identify and characterize the presence of @entity3479 ) in @entity10706 and platelets. We investigated the fibrinolytic activity of @entity1 @entity10706 ( @entity10706 ) and platelets. The presence of @entity3479 antigen in @entity10706 and platelets was demonstrated using immunocytochemical techniques and polyclonal or monoclonal antibodies specific for @entity3479 . When cells were applied to fibrin plates, lysis zones developed around isolated @entity1 @entity10706 , whereas no fibrinolytic activity appeared when either intact washed platelets or platelet lysate were deposited. After SDS-PAGE of platelet and @entity10706 extracts (Triton X-100) immunoblotting and peroxidase staining identified @entity3479 antigen in several bands. Zymographic analysis of SDS-PAGE carried out on fibrin film overlays identified one or two zones corresponding to free or complexed @entity3479 . These results indicate that @entity3479 is present in platelets as well as in the precursor cells, however, in platelets, @entity3479 may not be immediately available for plasminogen activation and fibrin degradation. From our findings and from previous work of others, it appears that platelets may either activate or inhibit the fibrinolytic system. Therefore the conditions of plasminogen activation by platelet @entity3479 and @entity1351 inhibition by platelet alpha 2-antiplasmin or other inhibitors have to be precised before the role of platelets in clot dissolution is understood. The physiological role of platelets in fibrinolysis and clot dissolution remains unclear. In 1953, the antifibrinolytic activity of blood platelets was demonstrated and in the early 1960's a fibrinolytic activity, increasing with platelet concentration in the experimental system, was shown.(ABSTRACT TRUNCATED AT 250 WORDS)
