Spotlight - Dr Sarah Hsiao

Stent deployment is widely accepted as the most efficient treatment available for occluded coronary arteries. However, a small percentage of patients are under the risk of severe complication due to incomplete endothelium repair. While little is known regarding this repair process, I was offered the project to examine the effect of stent-induced disruption in wall shear stress on endothelial behaviour by Prof Paul Evans. With the help of collaborators from various Departments and Universities, we established a versatile in vitro flow model that allows real time monitoring of endothelial cell behaviours. Using ridges to imitate the presence of stent strut in a blood vessel, we observed abnormal endothelial cell migration pattern within the region downstream from the ridges. As compared to cell migration over a flat surface, cells within the characteristic flow perturbation zone displayed loss of directionality and were incapable to generate a confluent monolayer. We thus propose the use of a pharmacological agent that intervenes the signalling pathway of flow on endothelial, which allows cell migration insensitive to the flow environment. We were very excited to find our hypothesis approved, where pharmacological intervention successfully rescued the loss of cell directionality within flow perturbation zone.

This work has been presented at various conferences and received positive feedbacks from experts in the field as well as the winning of Young Investigator Awards. We are currently examining whether the positive effect of Fasudil could be reproduced in vivo using a porcine stent deployment model. It is importantly to point out that a lot of people have contributed to this work and without their support this work would not have been as successful. I am very pleased to have joint Prof Evan’s group and the Department of Cardiovascular Science as my first postdoctoral position. It has been a spectacular team work from everyone and hopefully we will have some encouraging results from the in vivo works to complete the study by the end of the year.