From iPSCs to Engineered Heart and Liver Models: Modulating Genetic and Extracellular State for Maturity

The heart and liver are central to human physiology yet remain major sites of drug-induced toxicity, driving the need for robust, scalable, and physiologically relevant in vitro models. Induced pluripotent stem cell (iPSC)–derived hepatocyte-like cells (HLCs) and cardiomyocytes (iPSC-CMs) offer patient specificity and renewable cell sources, but both suffer from significant limitations in structural and functional maturity. This dissertation integrates multi-omic profiling, genetic engineering, biomaterials-based strategies, and microfabrication to advance the fidelity and utility of iPSC-derived hepatic and cardiac models. For hepatic differentiation, we employed RNA-seq and ATAC-seq across key differentiation stages to identify transcription factors and signaling pathways regulating hepatic fate. Three independent computational pipelines converged on high-confidence candidates spanning endodermal regulators, AP-1 complex members, and EMT-associated factors. Functional interrogation revealed that CRISPRa-mediated activation of early endoderm TFs enhanced hepatic function. siRNA knockdown of AP-1 family members, FOS, JUN, FOSL1, FOSL2 changed albumin secretion. Additional analyses showed persistent activation of EMT and TGF-β signaling in immature HLCs. Pharmacological inhibition of TGF-β receptors significantly improved albumin secretion and CYP1A2 metabolism across donors. In parallel, we evaluated extracellular matrix (ECM) biology in hepatic differentiation, finding that defined ECM proteins, decellularized liver ECM, and electrospun natural polymer nanofibers, substantially enhanced HLC function relative to traditional substrates, partly through modulation of YAP signaling. Complementary efforts focused on improving cardiac models. We developed subtype-specific cryopreservation methods for atrial and ventricular iPSC derived cardiomyocytes that preserved viability, chamber identity, electrophysiology, and drug responses. Additionally, we engineered a soft-lithographic micropatterning platform that generates aligned, fibroblast-supported cardiac tissues in multi-well plates. Epicardial-derived iPSC fibroblasts produced the strongest maturation effects, enabling fully patient-specific tissues suitable for disease modeling. Together, these advancements establish improved hepatic and cardiac platforms that enhance maturation, scalability, and predictive function, providing valuable tools for disease modeling and preclinical drug testing and disease modelling.

Author dc:creator

• Kristen Cotton (24400271)

• Engineering
• Biomedical

Statement dc:rights

• In Copyright
• Open Access after 2028-05-01

DOI dc:identifier

https://doi.org/10.25417/uic.32995316.v1

OAI identifier oai:identifier

oai:figshare.com:article/32995316