A Microfluidic Cell Culture Platform for Modeling Aligned Peripheral Nerve Bundle, Connection, and Myelination

The development of microfluidic platforms has advanced peripheral nervous system research; however, traditional polydimethylsiloxane (PDMS)-based systems lack scalability and physiological relevance. To overcome these limitations, we introduce a 3D-printed organ-on-a-chip that enables precise sensory neurite alignment and myelination studies in a standardized 384-well format. Our platform integrates open and closed microfluidic principles to ensure stable fluid dynamics. This design creates a controlled co-culture environment of primary sensory neurons (SN) - Schwann cells (SCs) that mimics in vivo nerve bundle organization. Finite element modeling and fluid dynamics simulations optimize nutrient distribution and biomechanical forces within the chip. Experimental results demonstrate that neurite alignment significantly enhances neuronal growth, with aligned neurites showing up to 2-fold greater area and length compared to random controls. This structured environment facilitates SCs-mediated myelination, producing compact myelin sheaths with physiologically relevant g-ratios (∼0.6) and nodes of Ranvier. Our platform also recapitulates both myelinated and non-myelinated Remak bundles observed in native sensory nerves. This platform is cost-effective, resource-efficient, and has high-throughput, making it a versatile tool for pain research, disease modeling, and regenerative medicine applications.