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Published on: September 9, 2012
A streptokinase dependent plasma factor (SKDF) induces leucocyte tissue factor activity
British Journal of Haematology
|December 1, 1988
Summary
Researchers discovered a novel plasma factor that, with streptokinase, activates leucocyte procoagulant activity. This streptokinase-dependent factor (SKDF) shows specific binding and may influence thrombolytic therapy.
Area of Science:
- Hematology
- Biochemistry
- Immunology
Background:
- Human leucocytes can be induced to express tissue factor-like procoagulant activity.
- The precise mechanisms and factors involved in this induction are not fully understood.
Purpose of the Study:
- To identify and characterize a novel plasma factor that enhances streptokinase-induced leucocyte procoagulant activity.
- To elucidate the mechanism of interaction between this factor, streptokinase, and leucocytes.
Main Methods:
- Investigated the interaction of plasma components with streptokinase and human leucocytes.
- Characterized the novel factor (SKDF) using dose-response curves, Hill plots, and stability assays.
- Differentiated SKDF from antibodies and other known activators.
Main Results:
- Identified a novel streptokinase-dependent factor (SKDF) in normal plasma/serum.
- Demonstrated specific, saturable, sigmoidal dose-response with a Hill coefficient of 2.2, indicating positive cooperativity.
- SKDF has high molecular weight, specific stability, and distinct leucocyte receptor interaction compared to endotoxins.
Conclusions:
- SKDF, in conjunction with streptokinase, induces potent leucocyte procoagulant activity via a cooperative mechanism.
- SKDF is distinct from antibodies and other plasminogen activators.
- SKDF may have a significant role in the efficacy and complications of thrombolytic therapy.
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