Engineering Pluripotent Stem Cells‐Derived Inner Ear Organoids With Enhanced Maturation and Reproducibility by Micro‐Topographical Cues

Abstract

ABSTRACT Inner ear organoids (IEOs) derived from pluripotent stem cells (PSCs) provide a promising platform for modeling neurosensory disorders and hearing loss; however, conventional systems often exhibit substantial structural variability, incomplete maturation, and limited reproducibility due to insufficient control of early organoid morphogenesis. Here, we demonstrate that micro‐topographical cues applied during initial IEO formation enhance the development and functional maturation of PSC‐derived IEOs. This microengineering strategy introduces temporally defined microscale geometric confinement to regulate early cell‐cell and cell‐extracellular matrix (ECM) interactions, thereby promoting epithelial organization and developmental fidelity. Microengineered IEOs (M‐IEOs) exhibit improved reproducibility and neurosensory maturation, including increased hair cell‐like populations, stereocilia‐like structures and kinocilium‐like features exhibiting a characteristic (9 × 2) + 2 microtubule organization. Functionally, M‐IEOs exhibit enhanced electrophysiological responsiveness, supported by complementary transcriptomic and in situ analyses indicating activation of inner ear lineage maturation pathways. Furthermore, we demonstrate the versatility of M‐IEOs by integrating them with a microfluidic vascular system to model vascular‐epithelial interactions and inflammatory responses, highlighting its potential for disease modeling and pharmacological screening. Together, these findings establish transient micro‐topographical guidance as an instructive regulator of inner ear organoid development and provide a robust, vascular‐compatible platform for neurosensory research, disease modeling, and translational screening applications.