Engineering cardiac models through advanced patterning technologies
File(s)
Author(s)
Pchelintseva, Ekaterina
Type
Thesis
Abstract
Recapitulating microscopic cellular organisation is key to the successful engineering of functional bioinspired tissues. In cardiac muscle, the alignment of cardiomyocytes plays a major role in the synchronization of conduction and contraction, necessary for efficient heart function. In vitro engineered cardiac models seek to replicate this structural and functional anisotropy; however, they require laborious fabrication methods, or have limited spatial resolution.
Here, two different advanced patterning approaches are combined with human induced pluripotent stem cell (hiPSC) differentiation protocols to produce three independent micropatterned cardiac models. Acoustic cell patterning is a non-invasive, label-free, cytocompatible technique, able to rapidly arrange cells within a fluid medium into uniform structures. First, the development process of a novel acoustic device is outlined, ultimately combining ultrasound fields with commercial multielectrode arrays to generate two-dimensional anisotropic arrays of hiPSC-derived cardiomyocytes (hiPSC-CMs) with the potential for quantifiable output. The resultant model adds a degree of structural complexity to standard monolayer cultures used for high-throughput drug screening. Second, 2½-dimensional anisotropic cardiac fibres with physiologically-relevant dimensions, improved electrophysiological properties and directional signal propagation are engineered by immobilising acoustically-patterned hiPSC arrays in hydrogels and subjecting them to cardiac differentiation in situ. Notably, this is the first demonstration of acoustic patterning of hiPSCs with subsequent directed differentiation, which is anticipated to be a valuable platform for engineering other spatially organised tissues. Third, an in situ cardiac differentiation protocol was applied to hiPSC clusters encapsulating a highly ordered fibrous scaffold, creating synchronous interconnected cardiac meshes suitable for the injured myocardium remuscularisation. The preliminary results of mesh-mediated cardiomyocyte transfer to an ex vivo cardiac tissue highlight the importance of interface stability and duration for efficient cell therapy.
Overall, the work of this thesis emphasises how implementing acoustic or material-guided cell patterning in cardiac engineering can improve the functional performance and biological relevance of next generation in vitro models.
Here, two different advanced patterning approaches are combined with human induced pluripotent stem cell (hiPSC) differentiation protocols to produce three independent micropatterned cardiac models. Acoustic cell patterning is a non-invasive, label-free, cytocompatible technique, able to rapidly arrange cells within a fluid medium into uniform structures. First, the development process of a novel acoustic device is outlined, ultimately combining ultrasound fields with commercial multielectrode arrays to generate two-dimensional anisotropic arrays of hiPSC-derived cardiomyocytes (hiPSC-CMs) with the potential for quantifiable output. The resultant model adds a degree of structural complexity to standard monolayer cultures used for high-throughput drug screening. Second, 2½-dimensional anisotropic cardiac fibres with physiologically-relevant dimensions, improved electrophysiological properties and directional signal propagation are engineered by immobilising acoustically-patterned hiPSC arrays in hydrogels and subjecting them to cardiac differentiation in situ. Notably, this is the first demonstration of acoustic patterning of hiPSCs with subsequent directed differentiation, which is anticipated to be a valuable platform for engineering other spatially organised tissues. Third, an in situ cardiac differentiation protocol was applied to hiPSC clusters encapsulating a highly ordered fibrous scaffold, creating synchronous interconnected cardiac meshes suitable for the injured myocardium remuscularisation. The preliminary results of mesh-mediated cardiomyocyte transfer to an ex vivo cardiac tissue highlight the importance of interface stability and duration for efficient cell therapy.
Overall, the work of this thesis emphasises how implementing acoustic or material-guided cell patterning in cardiac engineering can improve the functional performance and biological relevance of next generation in vitro models.
Version
Open Access
Date Issued
2022-12-16
Date Awarded
01/08/2023
License URL
Advisor
Stevens, Molly Morag
Terracciano, Cesare Maria Nicola
Sponsor
British Heart Foundation
Rosetrees Trust
Grant Number
British Heart Foundation
Rosetrees Trust
FS/17/74/33192
M763
Publisher Department
Materials
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)