Recreating arterial thrombosis models using tissue-engineered arterial constructs: A method to reduce and replace mice used in platelet research

Ranjbar, Jacob Ali

Abstract

Intravital microscopy in mice is widely used to study in vivo thrombus formation, however, the relevance of these studies to human physiology is unclear. In this thesis, a 3D tissue-engineered human arterial construct (TEAC) was developed that replicates the primary and secondary haemostatic properties of the native artery. This, in addition to a 3D printed microfluidics system developed here, could be used as an alternative to current mouse arterial thrombosis models. Experiments demonstrated that the tissue-engineered medial layer (TEML) is capable of triggering platelet activation and the extrinsic coagulation cascade. The TEML can produce endogenous human type I collagen and tissue factor. The expression of both of these vascular components could be enhanced by the TEMLs by the supplementation of the culture media with ascorbic acid. Ascorbic acid supplemented cultures have a significantly greater thrombotic response when exposed to human blood under physiological flow experiments. A tissue engineered intimal layer (TEIL) frame and adhesion method developed in this thesis was able to secure and maintain highly aligned nanofibers for the culture of a confluent intimal layer. Experiments demonstrated that the TEIL construct is successful at preventing platelet activation under physiological flow conditions. In this thesis a hobbyist 3D printer was used to develop a microfluidics chamber that is capable of housing the TEAC to allow for physiological flow of whole human blood over the construct. With addition to the standardised method of mechanical injury developed here it is possible to create reproducible thrombotic events within the model that is capable of supporting an occlusive thrombus. Antiplatelet and anticoagulant drugs were used to help validate this in vitro human thrombosis. Experiment under physiological flow, demonstrated that the in vitro model developed here can replicate the expected pharmacological sensitivities to thrombus formation in response to treatment with clinically relevant anti-thrombotic drugs. The data in this thesis demonstrates the capability of the human in vitro thrombosis model to replicate all the major haemostatic processes of the native blood vessel, and in doing so, has a potential to replace murine thrombosis models for pre-clinical drug testing.

Citation

Ranjbar, J. A. (2023). Recreating arterial thrombosis models using tissue-engineered arterial constructs: A method to reduce and replace mice used in platelet research. (Thesis). Keele University. Retrieved from https://keele-repository.worktribe.com/output/674551

• Thesis Type: Thesis
• Deposit Date: Dec 21, 2023
• Public URL: https://keele-repository.worktribe.com/output/674551
• Additional Information: Embargo on access until 16 July 2024 - The thesis is due for publication, or the author is actively seeking to publish this material.
• Award Date: 2023-12