Related Experiment Videos
Platelet adhesion and aggregation on human type VI collagen surfaces under physiological flow conditions
J M Ross1, L V McIntire, J L Moake
1Cox Laboratory for Biomedical Engineering, Rice University, Houston, TX77251, USA.
Blood
|April 1, 1995
Summary
Platelet interaction with collagen VI is shear-rate dependent, with significant adhesion occurring at low shear rates. von Willebrand factor (vWF) plays a crucial role in this process, mediated by platelet glycoprotein receptors.
Area of Science:
- Biochemistry
- Hematology
- Biophysics
Background:
- Type VI collagen is a key component of the subendothelium.
- It interacts with von Willebrand factor (vWF) and platelets, influencing hemostasis.
- Understanding these interactions is crucial for vascular biology.
Purpose of the Study:
- To investigate platelet interaction with type VI collagen under flow conditions.
- To elucidate the roles of platelet glycoprotein receptors and vWF in this interaction.
- To compare collagen VI's shear rate-dependent adhesion with collagen I.
Main Methods:
- Epi-fluorescent videomicroscopy coupled with digital image processing.
- Utilized monoclonal antibodies against platelet GPIb and GPIIb-IIIa, and aurin tricarboxylic acid.
- Studied blood from patients with von Willebrand disease.
Main Results:
- Platelet surface coverage on collagen VI was low at high shear rates (1,000 s-1) but high (~60%) at low shear rates (100 s-1).
- Anti-GPIIb-IIIa antibodies most effectively reduced adhesion, followed by anti-GPIb and ATA.
- von Willebrand factor is involved in platelet adhesion to collagen VI at low shear rates.
Conclusions:
- Platelet adhesion to collagen VI is highly dependent on shear rate, favoring low shear conditions.
- von Willebrand factor and platelet glycoprotein receptors (GPIb, GPIIb-IIIa) are critical mediators.
- Collagen VI may play a significant role in platelet adhesion and aggregation in low shear vascular regions.