Engineering ECM-inspired hydrogel scaffolds with complex geometries for hepatic tissue models through projection micro-stereolithography

Ana Valeria Gonzalez Abrego

Engineering ECM-inspired hydrogel scaffolds with complex geometries for hepatic tissue models through projection micro-stereolithography

Publication Date

July 27, 2026

Creator

Ana Valeria Gonzalez Abrego

Abstract

The liver’s extracellular matrix (ECM) exhibits a highly heterogeneous and hierarchical architecture that is essential for regulating hepatocyte organisation, mechanotransduction, and metabolic function. Reproducing these complex structural cues in-vitro remains a major challenge for hepatic tissue engineering, where most existing scaffolds rely on oversimplified geometries that limit functional maturation. This thesis integrates computational design, ECM analysis, and high-resolution biofabrication to investigate how ECM-inspired 3D architectures influence hepatocellular behaviour, with the overarching aim of establishing design principles for next-generation liver models. Decellularised liver ECM was first characterised to extract quantitative architectural descriptors which were subsequently abstracted into four representative scaffold geometries: Stochastic (ECM-mimetic), Isotruss, Gyroid, and Cubic. To fabricate these designs with micron-scale fidelity, a hybrid GelMA–PEGDA hydrogel was developed and systematically optimised for projection micro-stereolithography (PμSLA). The resulting bioresin enabled reproducible fabrication of highly resolved lattices with tunable stiffness and excellent cytocompatibility. Using these scaffolds, HepG2 hepatocytes were cultured for 14 days to assess geometry-dependent differences in viability, organisation, and functional maturation. The Stochastic scaffold, capturing the irregular, biomimetic features of native ECM, promoted rapid formation of multicellular aggregates, reduced HNF6 expression, and early upregulation of hepatic function. This was reflected in significantly enhanced urea synthesis and albumin secretion at days 3 and 7, along with sustained performance through day 14. In contrast, the periodic Isotruss and Gyroid geometries showed modest early activity but exhibited marked functional improvements by day 14, including strong albumin production and elevated CYP3A4 enzymatic activity. These findings suggest that ordered lattices support a slower but ultimately effective maturation trajectory as tissue consolidation progresses. Genetic expression analysis indicates that the heterogeneous microenvironment of the Stochastic scaffold might reduce cytoskeletal tension and enhances cell–cell junction formation, enabling early activation of hepatic transcription factors such as HNF4α and downstream metabolic pathways. Together, these results demonstrate that scaffold architecture influences not only the magnitude of hepatocyte function but also the temporal progression of maturation. This work establishes a clear structure–function relationship linking ECM-inspired architectural cues, bioresin optimisation, and high-resolution PμSLA fabrication to hepatocellular performance. The insights generated offer a rational foundation for designing biomimetic scaffolds that more faithfully recapitulate hepatic microenvironments, advancing the development of physiologically relevant liver models for drug screening, disease modelling, and regenerative medicine.

Item Type

ethesis

Thesis Type

PhD

Supervisors

Hague, Richard