Effects of Thrombin on the Mechanical Properties of Clots

Open Access
- Author:
- Elko, Evan
- Area of Honors:
- Biomedical Engineering
- Degree:
- Bachelor of Science
- Document Type:
- Thesis
- Thesis Supervisors:
- Keefe B Manning, Thesis Supervisor
Jian Yang, Thesis Honors Advisor
Justin R Pritchard, Faculty Reader - Keywords:
- Thrombin
Coagulation
Rotational Thromboelastometry
Mechanical Testing
Thrombosis - Abstract:
- Cardiovascular disease (CVD) is the leading cause of death for men and women in the United States. To create in vitro thrombi that model those seen in various types of cardiovascular diseases, researchers often use thrombin to initiate the coagulation cascade. However, it has been shown that a change in thrombin concentration can alter the mechanical properties of a thrombus. The present study uses rotational thromboelastomery (RoTEM), and a mechanical compression test to examine how the properties of thrombi are affected by a change in the thrombin concentration used to create them. In the RoTEM studies, whole human blood is mixed with reagents to trigger different pathways of the coagulation cascade. Varying thrombin concentrations are added to the samples, and the resistance of the sample is measured with respect to time. The intrinsic and extrinsic pathways experience a decrease in initial clotting time and maximum clot firmness with an increase in thrombin concentration. Similar results are obtained when using bovine blood. The common pathway does not experience any significant changes for any parameters when using human blood. When using bovine blood, initial clotting time was reduced with an increase in thrombin concentration. In the mechanical compression studies, different effects are observed. As thrombin concentration was increased in the clot formation process, the compressive strength of the clot increased until plateauing at 10 µg/mL. This trend held true for clots allowed to form for 20 minutes and for 3 hours. The findings from these studies provide insight into how varying thrombin concentrations have an impact on the mechanical properties of blood clot analogues formed in vitro. A better overall understanding of these properties can lead to more accurate results on experiments that study cardiovascular diseases using thrombin-formed blood clots.