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Updated: Jun 10, 2026
In Vitro Microfluidic Disease Model to Study Whole Blood-Endothelial Interactions and Blood Clot Dynamics in Real-Time
Published on: May 24, 2020
Microparticle formation after exposure of blood to activated endothelium under flow
Marion G Macey1, Sabine I Wolf, Charlotte Lawson
1Department of Haematology, The Royal London Hospital, London, UK.
Abstract:
Increased numbers of circulating microparticles (MPs) are indicative of poor clinical outcome in a number of inflammatory disorders, including atherosclerosis. Platelets and megakaryocytes are a major source of MP and are identified by presence of CD42b on the MP surface. MP shed from activated platelets can be identified by presence of P-selectin (CD62P). Tissue factor (TF) is the principal initiator of blood coagulation and its activity has been identified in MPs derived from patient plasma, which may contribute to thrombosis. Here, we have investigated by flow cytometry the expression of TF and CD62P on MP after exposure of diluted whole blood to TNF-activated endothelial cells (EC) both under static conditions and in our newly established model of flow. MPs were significantly increased in blood subjected to flow and this was further enhanced after exposure of blood to TNF-activated EC. MP surface expression of CD62P or TF was upregulated following exposure to TNF-activated EC under flow compared with flow with nonactivated EC or after static coculture with and without prior EC activation. These data strongly suggest that interactions of blood with inflamed EC can modulate production of CD62P and TF bearing MP under flow conditions, and thus may contribute to a prothrombotic environment.
Insights
Circulating microparticles (MPs) increase with blood flow and inflamed endothelial cells, showing elevated P-selectin (CD62P) and tissue factor (TF). This suggests a prothrombotic state in inflammatory disorders like atherosclerosis.
Area of Science:
- Hematology
- Cardiovascular Biology
- Inflammation Research
Background:
- Increased circulating microparticles (MPs) correlate with poor outcomes in inflammatory diseases such as atherosclerosis.
- Platelets and megakaryocytes are primary sources of MPs, identifiable by CD42b.
- MPs from activated platelets express P-selectin (CD62P), and tissue factor (TF) on MPs can initiate blood coagulation and thrombosis.
Purpose of the Study:
- To investigate the expression of TF and CD62P on MPs.
- To analyze MP changes in response to TNF-activated endothelial cells (EC) under static and flow conditions.
Main Methods:
- Flow cytometry was used to analyze MP expression.
- Diluted whole blood was exposed to TNF-activated EC under static and flow conditions.
Main Results:
- MPs significantly increased under flow conditions, further elevated after exposure to TNF-activated EC.
- MP surface expression of CD62P and TF was upregulated upon exposure to TNF-activated EC under flow compared to static conditions or non-activated EC.
Conclusions:
- Interactions between blood and inflamed ECs modulate the production of CD62P and TF-bearing MPs under flow.
- These findings suggest a potential contribution to a prothrombotic environment in inflammatory conditions.
