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10:10
Platelet Adhesion and Aggregation Under Flow using Microfluidic Flow Cells
Published on: October 27, 2009
Finite platelet size could be responsible for platelet margination effect
A A Tokarev1, A A Butylin, E A Ermakova
1National Research Center for Hematology, Ministry of Health and Social Development of Russian Federation, Moscow, Russia.
Biophysical Journal
|October 19, 2011
Summary
Platelets migrate to blood vessel walls due to their size, not just flow dynamics. This erythrocyte-driven margination is key for hemostasis.
Area of Science:
- Biophysics
- Hematology
- Rheology
Background:
- Blood flow exhibits segregation: erythrocytes central, platelets peripheral.
- Platelet margination to vessel walls is crucial for hemostasis.
- Mechanisms of platelet margination are not fully understood.
Purpose of the Study:
- To develop a mathematical model predicting platelet distribution in blood flow.
- To investigate the role of erythrocyte presence in platelet margination.
Main Methods:
- Constructed a mathematical model incorporating platelet and erythrocyte dimensions.
- Assumed even platelet distribution between erythrocytes.
- Validated model predictions against experimental data for margination and migration.
Main Results:
- Model accurately predicts platelet distribution and near-wall margination.
- Finite platelet size impedes their central positioning among erythrocytes.
- Erythrocytes actively expel platelets from the vessel core.
Conclusions:
- Platelet margination is significantly influenced by erythrocyte crowding.
- Platelet size and erythrocyte interactions are primary drivers of margination.
- Provides new insights into rheological control of platelet hemostasis.
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