Due to controversial evidence in the literature pertaining to the activity of plasminogen activator inhibitor-1 in platelets, we examined the effects of residual platelets present in plasma (a potential pre-analytical variable) on various plasminogen activator inhibitor-1 and plasminogen activator inhibitor-1-related assays. Blood samples were collected from 151 individuals and centrifuged at 3...

Because of its enhanced activation of plasminogen in association with fibrin compared with free plasminogen, tissue-type plasminogen activator (t-PA) evoked excitement as a potentially useful pharmacologic activator of the fibrinolytic system. Initial studies in experimental animals and patients demonstrated that it induced coronary thrombolysis rapidly and without concomitant, marked fibrinoge...

Tryptase is a member of the chromosome 16p13.3 family of human serine proteases that is preferentially expressed by epithelial cells. Recombinant pro– tryptase was generated to understand how the exocytosed zymogen might be activated outside of the epithelial cell, as well as to address its possible role in normal and diseased states. Using expression/site-directed mutagenesis approaches, we no...

Plasminogen activator inhibitor-1 (PAI-1) is the major specific inhibitor of tissue-type plasminogen activator (tPA) which mediates fibrin clot lysis through activation of plasminogen. Wild-type-PAI-1 (wPAI-1) is rapidly converted to the latent form (half-life of approximately 2 h) and loses its ability to inhibit tPA. We developed a very long half-life PAI-1 (VLHL PAI-1), a recombinant protein...

Single-chain urokinase plasminogen activator (scuPA), the unique form secreted by cells, expresses little intrinsic plasminogen activator activity. scuPA can be activated by proteolytic cleavage to form a two-chain enzyme (tcuPA), which is susceptible to inhibition by plasminogen activator inhibitor type I (PAI-1). scuPA is also activated when it binds to its cellular receptor (uPAR), in which ...

The vampire bat salivary plasminogen activator (Bat-PA) is a potent PA that exhibits remarkable selectivity toward fibrin-bound plasminogen (Gardell et al, J Biol Chem 256: 3568, 1989). Herein, we describe the activity of recombinant DNA-derived Bat-PA (rBat-PA) in a human plasma milieu. rBat-PA and recombinant human single-chain tissue plasminogen activator (rt-PA) are similarly efficacious at...

Carcinogenesis in the human colon is associated with a marked increase of urokinase type plasminogen activator and a decrease of tissue type plasminogen activator. This study was performed to determine the concentrations of urokinase type plasminogen activator and tissue type plasminogen activator in normal tissue and carcinomas along the upper part of the gastrointestinal tract. Activity and a...