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Updated: Jan 31, 2026
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Analysis of Shear Flow-induced Migration of Murine Marginal Zone B Cells In Vitro
Published on: November 26, 2018
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Marginal Band Collapsing: Structural Insights Into Shear-Induced Platelet Activation Relevant to Circulatory Assist
Randy Perez1, Kevin Ho1, John Vandenberge1
1From the Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland; and.
ASAIO Journal (American Society for Artificial Internal Organs : 1992)
|January 30, 2026
Summary
Mechanical circulatory support (MCS) devices can activate platelets, increasing thrombosis and bleeding risks. This study found that marginal band (MB) collapse in platelets correlates with activation, offering a new way to assess device-induced platelet changes.
Area of Science:
- Biomedical Engineering
- Hematology
- Cardiovascular Research
Background:
- Mechanical circulatory support (MCS) devices are crucial for patients with heart failure.
- Shear stress from MCS devices can paradoxically increase thrombosis and bleeding risks due to platelet activation and receptor shedding.
- The role of the platelet marginal band (MB) in shear-induced activation and its correlation with flow cytometry markers are not well understood.
Purpose of the Study:
- To investigate marginal band (MB) alterations in platelets activated by shear stress from MCS devices.
- To correlate MB collapse with flow cytometric markers of platelet activation and receptor shedding.
- To evaluate MB collapse as a potential biomarker for shear-induced platelet activation.
Main Methods:
- Human blood was circulated through an MCS device for 4 hours under varying pressure heads (75-350 mm Hg).
- Platelet activation (PAC-1, P-selectin) and glycoprotein receptor shedding (GPIbα, GPVI, GPIIb/IIIa) were quantified using flow cytometry.
- Marginal band (MB) collapse was microscopically examined and classified.
Main Results:
- Platelet activation, receptor shedding, and MB collapse increased progressively with higher pressure heads.
- Marginal band collapse showed a strong correlation with platelet activation markers.
- Marginal band collapse exhibited significant heterogeneity among activated platelets, reflecting a complex response to shear stress.
Conclusions:
- Marginal band (MB) collapse is closely associated with shear-induced platelet activation in MCS devices.
- MB collapse can serve as an effective assay for evaluating platelet activation caused by MCS.
- Understanding MB dynamics provides insights into platelet mechanobiology under artificial circulatory conditions.
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