*********************************
There is now a CONTENT FREEZE for Mercury while we switch to a new platform. It began on Friday, March 10 at 6pm and will end on Wednesday, March 15 at noon. No new content can be created during this time, but all material in the system as of the beginning of the freeze will be migrated to the new platform, including users and groups. Functionally the new site is identical to the old one. webteam@gatech.edu
*********************************
Aline L.Y. Nachlas
BME Ph.D. Defense Presentation
Date: Monday, May 20th, 2019
Time: 3:00 PM
Location: HSRB E160
Committee Members:
Michael E. Davis, PhD (Advisor)
K. Jane Grande-Allen, PhD
Wilbur Lam, MD, PhD
Wei Sun, PhD
Johnna S. Temenoff, PhD
Chunhui Xu, PhD
Title: Engineering an aortic valve with cellular and mechanical functionality
Abstract: Heart valve disease is an increasing clinical burden associated with high morbidity and mortality. Current, valve replacements have a number of risks, such as thrombogenicity and calcification. For pediatric patients, a significant issue is the lack of small implants capable of growing, resulting in several surgical interventions for valve refitting. Patient-specific, tissue engineered heart valves (TEHVs) have the potential to address these issues through their self-repairing and remodeling capacity. The overall objective of this thesis was to develop a TEHV that functions under physiological aortic valve conditions and has the potential to repair and remodel over time. The central hypothesis is a TEHV can be created by mimicking the structural components of the valve leaflet layers using 3D bioprinting and incorporating valvular interstitial cell (VIC)-like cells to actively regenerate and remodel. First, we generated a potential suitable cell source of human iPSC-derived mesenchymal stem cells (iMSCs) that mature into VIC-like cells. Next, we used 3D printing and a combination of poly-ε-caprolactone (PCL) and gelatin methacrylate - polyethylene (glycol) diacrylate (GelMA/PEGDA) hydrogel to create a cell-laden multilayered leaflet that recapitulates the layers of the valve leaflet. Lastly, the PCL component of the valve leaflet was mounted onto a valve stent and feasibility studies were conducted using a left-ventricle flow simulator to evaluate the hemodynamic performance of the PCL-TEHV under aortic valve conditions. We demonstrated a cell source can be derived from autologous iPSCs, generated a multilayered leaflet scaffold using a combination of natural and synthetic biomaterials, and verified the feasibility of the leaflet under aortic flow conditions. These promising findings are the first steps to a pre-clinical TEHV with the ability to regenerate and remodel with the patient.
