Plasminogen activators (t-PA, u-PA)


  u-PA (urokinase) t-PA
Single-chain form single-chain urokinase (sc u-PA),
Prourokinase, inactive form
single-chain tissue-type
plasminogen activator, sc t-PA
Two-chain form two-chain Urokinase (tc u-PA),
Urokinase, active form
two-chain tissue-type
plasminogen activator, tc t-PA
Molecular mass 54 000 D 68 000 D
Half-life 5 - 10 minutes 4 - 5 minutes
Plasma concentration 2 - 8 ng/ml 5 ng/ml total t-PA antigen
1 ng/ml free t-PA antigen
0.5 IU/ml t-PA activity
Note: Individual and circadian variations
Synthesis kidneys, lungs endothelial cells
Primary structure 411 amino acids 530 amino acids

The most important plasminogen activator in plasma is t-PA. Similar to plasminogen, t-PA shows a high binding affinity to fibrin via specific binding sites. The originally weak activation capacity of t-PA is considerably accelerated in the presence of fibrin. In this way, fibrin bound plasminogen is preferentially activated. This results in the lysis of the fibrin clot from the inside. u-PA only plays a minor role as plasminogen activator in plasma. It is of importance in tissue transformation, cell migration and tumor metastasis in the extravasal space. Single-chain prourokinase is activated to the two-chain form by kallikrein.

Clinical significance

Patients showing a reduced release of t-PA following occlusion or DDAVP infusion are called "non-responders". They have an increased risk for thromboembolic complications such as venous or arterial occlusion, apoplexy and coronary diseases. Increased t-PA values are observed in stress, tumor diseases, liver transplantations and hepatic failure.


  • Diagnosis of thrombophilia
  • Suspected increase or decrease of fibrinolytic potential


  1. Meijer P et al. The use of Stabilyte plasma may cause changes in pH in the assay of some fibrinolysis analytes and might effect results. Fibrinolysis 10 (Suppl. 2), 155-157, 1996.
  2. Geppert A et al. Concentration of Endogenous t-PA Antigen in Coronary Artery Disease. Arterioscler Thromb Vasc Biol 18, 1634-1642, 1998.
  3. Roldán-Olarte M, García DC, Jiménez-Díaz M, Valdecantos PA, Miceli DC. In vivo and in vitro expression of the plasminogen activators and urokinase type plasminogen activator receptor (u-PAR) in the pig oviduct. Anim Reprod Sci. Dec 136(1-2), 90-9, 2012.
  4. Keller L, Hobohm C, Zeynalova S, Classen J, Baum P. Does treatment with t-PA increase the risk of developing epilepsy after stroke? J Neurol. Oct 262(10), 2364-72, 2015.
  5. Rosen S et al. Evaluation of a bioimmuno assay for t-PA activity and its relation to PAI-1 activity and antigen levels. Fibr Proteol 12, 340-346, 1998.
  6. Kluft C, Meijer P. Update 1996: Blood collection and handling procedures for assessment of plasminogen activators and inhibitors (Leiden Fibrinolysis Workshop), Fibrinolysis 10 (Suppl. 2) 171-179, 1996.
Test kits
ELISA Complete Kits

ELISA t-PA Actibind®

Short Info Request personal insert

ELISA u-PA Antigen

Short Info Request personal insert

ELISA u-PA Actibind®

Short Info Request personal insert

ELISA t-PA/PAI-1-Complex

Short Info Request personal insert

Matched-Pair Antibody Set


Short Info

We are here for you

Haemochrom Diagnostica GmbH
Renteilichtung 1
45134 Essen

Phone: +49 (0)201 8 43 77-0
Fax: +49 (0)201 53 64 56

Send us a message