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Updated: May 31, 2026
04:32
A Uniform Shear Assay for Human Platelet and Cell Surface Receptors via Cone-plate Viscometry
Published on: June 5, 2019
Effects of physiologically relevant dynamic shear stress on platelet complement activation.
Saravan Kumar Shanmugavelayudam1, David A Rubenstein, Wei Yin
1School of Mechanical and Aerospace Engineering, Oklahoma State University, Stillwater, USA.
Platelets
|June 18, 2011
Summary
Low-pulsatile shear stress initiates platelet complement activation, while pathological shear stresses increase regulatory proteins, preventing full complement activation. Low-pulsatile shear stress may be more pro-atherogenic.
Area of Science:
- Cardiovascular Science
- Immunology
- Biophysics
Background:
- Disturbed shear stress in cardiovascular diseases impacts platelet function.
- Activated platelets can support complete complement activation.
- Understanding shear stress effects on platelets is crucial for disease insights.
Purpose of the Study:
- To investigate platelet complement activation under varying physiological shear stresses.
- To assess the role of shear stress in initiating and regulating complement pathways on platelets.
- To compare the pro-atherogenic potential of different shear stress conditions.
Main Methods:
- Platelets were exposed to three distinct shear stresses using a dynamic cone and plate device.
- Platelet-surface complement activation markers (C1q, C4d, iC3b, SC5b-9) were quantified via ELISA and flow cytometry.
- Production of complement regulatory proteins (C1-inhibitor, CR1) was measured.
Main Results:
- Low-pulsatile shear stress (recirculation) significantly increased C1q deposition, initiating complement activation.
- Pathological shear stresses elevated C1 inhibitor and altered CR1 production.
- These regulatory changes prevented the completion of complement activation.
Conclusions:
- Low-pulsatile shear stress may initiate platelet complement activation, potentially contributing to atherogenesis.
- Elevated shear stress, particularly with short exposure, triggers regulatory responses that limit complement activation.
- Platelet response to shear stress is complex, with low-pulsatile flow potentially being more detrimental.
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