Summary
Utilizing the immunoglobulin fraction from a goat antiserum against human uterine
tissue plasminogen activator, an enzyme- linked immunoassay for tissue-type plasminogen
activator in human plasma has been developed. With the new method, the concentration
of t-PA in normal human acidified plasma is found to be 4.0 ± 1.8 (SD) ng/ml. It increases
to 12 ng/ml after a tomiquet test, and to 14 ng/ml after strenous physical exercise.
In a group of patients with idiopathic thromboembolic disease, the resting t-PA concentration
was 5 ng/ml and the post-occlusion value 16 ng/ml. Furthermore, the patients also
exhibited a normal post-occlusion rise in the concentration of plasmin-α2-antiplasmin complex. However, in 37% of the post-occlusion patient plasmas, virtually
no increase in t-PA could be detected by a specific activity assay. The results indicate
that the reason for a defective post-occlusion fibrinolytic activity in a majority
of cases may be the presence of increased concentrations of a fast-acting specific
t-PA inhibitor.
Keywords
ELISA - Tissue-type plasminogen activator - Thromboembolic disease
