Adult stem cells, also known as tissue-specific progenitor cells, are a vital subpopulation responsible for maintaining tissue homeostasis. They play a central role in preserving tissue function and enabling epithelial regeneration after injury. Disruptions in their biology are linked to impaired wound healing and the development of chronic diseases such as fibrosis and cancer.

However, studying the mechanisms that govern progenitor cell behavior remains challenging. Epithelial tissues are complex, with heterogeneous differentiation states, and progenitor cells are rare. This scarcity of biological material, combined with the difficulty of isolating these cells without altering their intrinsic properties, limits routine mechanistic investigations.

Advances in biomaterials suggest that culturing cells on soft matrices—both in two-dimensional (2D) and three-dimensional (3D) formats—can help preserve progenitor-like characteristics. Yet, each format has limitations. While 3D models better mimic tissue architecture, they also introduce heterogeneity that can bias results. Conversely, 2D hydrogels provide a more practical and standardized platform, but their physiological relevance remains uncertain.

These observations raise two key questions:

Can soft matrix-based systems reveal specific mechanisms that govern progenitor cell biology?

How relevant and translatable are these mechanisms to human physiology?

To address these questions, we developed a novel multiwell hydrogel plate platform that improves interwell homogeneity and provides consistent mechanical stiffness. Compatible with standard laboratory techniques, it enables the generation of uniform material for molecular, biochemical, and functional analyses.

Using this system, we demonstrate that physiological stiffness cues reprogram epithelial cells to reacquire molecular and phenotypic traits of adult human progenitor cells. This reprogramming is driven by extensive translational rewiring and the chronic activation of proteostasis-related stress pathways, which regulate cellular quiescence and S-phase checkpoint control.

These findings highlight the utility of soft matrix systems—particularly our hydrogel platform—for uncovering conserved regulatory mechanisms of progenitor cell biology and underscore the role of intrinsic stress-response pathways in maintaining the progenitor state.