Plasmin on adherent cells: from microvesiculation to apoptosis
Loïc Doeuvre1, Laurent Plawinski, Didier Goux
1Inserm U919, GiP Cyceron, Bd Henri Becquerel, 14074 Caen, France.
The Biochemical Journal
|September 18, 2010
Summary
Plasmin activation on cell surfaces triggers membrane blebbing and microparticle release, signaling potential apoptosis. This process helps distinguish activated cells from those undergoing programmed cell death.
Area of Science:
- Cell Biology
- Biochemistry
Background:
- Cell activation by stressors involves phenotypic changes like phosphatidylserine exposure and microparticle release.
- These changes can precede cell detachment-induced apoptosis if the stimulus persists.
Purpose of the Study:
- To investigate the effects of plasmin on adherent cells.
- To characterize the membrane changes induced by plasmin and compare them to other stimuli.
- To establish a method for distinguishing activated cells from apoptotic cells.
Main Methods:
- Incubating plasminogen with adherent cells in the presence of tissue-type plasminogen activator (tPA) or urokinase-type plasminogen activator (uPA).
- Observing membrane blebbing, vesiculation, and microparticle release.
- Assessing matrix protein degradation, cell detachment, and DNA fragmentation.
Main Results:
- Plasmin formed on the cell membrane induced membrane blebbing and vesiculation, similar to thrombin's effect on platelets.
- Persistent plasmin formation led to matrix degradation, cell detachment, and apoptosis.
- The study proposes a method to differentiate activated adherent cells from apoptotic cells.
Conclusions:
- Plasmin-induced membrane changes serve as an early indicator of cell activation.
- The experimental procedure can reliably distinguish between cell activation and apoptosis.
- This distinction is vital for evaluating therapeutic agents targeting cell responses.
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