StrataChip: a microphysiological system capturing dynamic keratinocyte fate and mechanical transitions during human...

Epidermal development and homeostasis require precise coordination between keratinocyte differentiation and mechanics. Still, the mechanisms integrating these processes remain poorly understood in part due to limitations of existing experimental systems. Here, we introduce StrataChip, a tractable microphysiological system that enables dynamic, multimodal interrogation of human epidermal morphogenesis. The platform integrates a media perfused dermal tissue with human epidermal keratinocytes within a microfluidic device and supports rapid epidermal stratification following establishment of an air-liquid interface. High-resolution confocal imaging and single-cell RNA-sequencing demonstrate that the StrataChip recapitulates key architectural and molecular features of human epidermis, including distinct basal, spinous, and granular layers defined by canonical differentiation markers and adhesion molecule organization. Single-cell profiling reveals transcriptionally distinct basal and spinous subpopulations, including transitional states associated with suprabasal commitment. Live 3D imaging in situ captures keratinocyte morphodynamics including basal cell delamination and asymmetric division, linking dynamic cellular behaviors to defined differentiation fates and stratification. Altogether, StrataChip provides a robust platform for a dynamic and mechanistic interrogation of how gene regulation and cell mechanics are coupled during epidermal morphogenesis.