A microfluidic model of hemostasis sensitive to platelet function and coagulation.

Area of Science:

• Biomedical Engineering
• Hematology
• Microfluidics

Background:

• Hemostasis, the process of sealing vascular injuries, is crucial for arresting bleeding.
• Existing models primarily focus on intravascular thrombus formation, with limited options for studying extravascular thrombus formation.
• Understanding extravascular hemostasis is vital for managing bleeding disorders and trauma.

Purpose of the Study:

• To develop and validate a microfluidic model simulating extravascular thrombus formation.
• To investigate the roles of coagulation and platelet function in hemostasis using this model.
• To provide a platform for studying coagulopathies and platelet dysfunction.

Main Methods:

• A microfluidic device was engineered with vascular, vessel wall, and extravascular compartments.
• Type I collagen and tissue factor were used to promote platelet adhesion and initiate coagulation.
• Hemostatic challenges were simulated by inhibiting Factor VIII (hemophilia A model) and using a P2Y12 antagonist.

Main Results:

• The model successfully formed a stable thrombus, arresting blood loss into the extravascular space within approximately 7.5 minutes.
• Inhibition of Factor VIII led to unstable thrombi and failure to close the injury, mimicking hemophilia A.
• P2Y12 antagonist treatment doubled the hemostasis closure time, indicating the impact of platelet function.

Conclusions:

• The developed microfluidic model effectively replicates extravascular hemostasis and thrombus stabilization.
• The model is sensitive to both coagulation and platelet function, making it suitable for studying bleeding disorders.
• This platform offers a valuable tool for preclinical research on coagulopathies and platelet disorders.