Measurement of tPA and tPA-PAI-1 complexes by ELISA, using monoclonal antibodies: clinical relevance.
Two ELISA methods using monoclonal antibodies, are described for the measurement of tPA:Ag and tPA-PAI-1 complexes. On normal population tPA:Ag was found with a mean value of 5 ng/ml. Furthermore, despite that tPA activity was very low, only 50% (mean value) was measured as stable complexes with PAI-1. Important increase of tPA:Ag was observed in various pathologies (cardiac infarction, septicemia, respiratory distress syndrome). In liver disease, tPA:Ag reached high levels up to 100 ng/ml. Impaired liver clearance can potentiate the increased concentration which results from endothelial release. In all patients with elevated tPA:Ag level, 70 to 100% of tPA was complexed to PAI-1. Excess release of PAI-1 accompanys the increased release of tPA as it is proved by presence of high residual PAI-1 activity. Addition of exogeneous tPA to these pathological plasmas induced a high increase in tPA-PAI-1 complexes. Venous stasis in normal population resulted in a parallel increase of tPA:Ag and tPA-PAI-1 complexes. Although about a two fold increase was obtained for both parameters, post venous stasis plasma presented a much higher fibrinolytic activity while PAI-1 activity was moderately elevated. tPA:Ag and tPA-PAI-1 complexes have diagnosis and prognosis value in various pathologies as indicators of stimulated release of fibrinolysis activator and inhibitor.
Amiral
J
J
DIAGNOSTICA STAGO, Immunological Research Laboratory, Franconville, France.
Plassart
V
V
Grosley
M
M
Mimilla
F
F
Contant
G
G
Guyader
A M
AM
D000818:Animals; D000911:Antibodies, Monoclonal; D002138:Calibration; D004797:Enzyme-Linked Immunosorbent Assay; D006023:Glycoproteins / Q000032:analysis*; D006801:Humans; D006825:Hybridomas; D051379:Mice; D015849:Plasminogen Inactivators; D010959:Tissue Plasminogen Activator / Q000032:analysis* / Q000037:antagonists & inhibitors
D000911:Antibodies, Monoclonal; D006023:Glycoproteins; D015849:Plasminogen Inactivators; D010959:Tissue Plasminogen Activator