Abstract: Stem cell mechanobiology explores how physical factors, particularly extracellular matrix (ECM) stiffness, influence organogenesis and stem cell fate acquisition. As stem cell-based therapies advance, one being islet transplantation for diabetes, optimising beta cell differentiation and maturation remains a critical challenge. While biochemical signalling pathways are well understood and form the basis of current differentiation protocols, the role of mechanical properties in stem cell differentiation remains poorly understood. However, many current protocols rely on a transition from 2D to 3D culture at specific stages, and connections between mechanosensors like YAP1 and endocrine fate acquisition have been suggested, both underscoring the need for a better understanding of the underlying physical cues. Nonetheless, physiological stiffness ranges during human fetal pancreas development have yet to be reported. In this study, we present comprehensive stiffness maps of the developing human pancreas from 8 to 23 weeks post-conception, generated using contact-based Atomic Force Microscopy. These measurements suggest stiffness ranges of 50–250 Pa with ongoing stiffening over time, which we replicate in-vitro using a synthetic hydrogel system. We have optimised a fully tunable hyaluronic acid-based hydrogel for culturing iPSC-derived pancreas organoids which retain a progenitor phenotype and can be further differentiated to beta cells. With this setup, we aim to investigate whether tuning ECM stiffness during in-vitro beta cell differentiation can enhance the efficiency of iPSC differentiation into insulin-producing beta cells. This research wants to highlight the importance of mechanical factors for stem cell fate decisions and aims to offer new insights into how biophysical cues can improve regenerative medicine strategies for diabetes.
Funding Source: This work was supported by the Biotechnology and Biological Sciences Research Council [grant number BB/T008709/1]
