Advancing nerve regeneration: Peripheral nerve injury (PNI) chip empowering high-speed biomaterial and drug screening

Peripheral nerve injuries (PNIs) represent a significant challenge in regenerative medicine, often leading to long-term functional impairments. In this study, we introduce the peripheral nerve injury-on-a-chip (PNI chip), a cutting-edge platform designed for high-speed screening of biomaterials and drugs to enhance peripheral nerve regeneration. The PNI chip combines aligned nanofibers as topographical cues with microfluidic technology to create a controlled and versatile environment for investigating key factors influencing axonal growth and regeneration. Our study reveals that density of aligned nanofibers plays a pivotal role in axonal regeneration regarding regeneration velocity and the recovery of damaged axonal areas. Additionally, we investigate the dynamic interactions between regenerating axons and aligned nanofibers, shedding light on the adaptability of axonal growth cones to topographical cues. Moreover, the PNI chip serves as a potent tool for drug screening, as demonstrated by our evaluation of paclitaxel and M1. Paclitaxel exhibits concentration-dependent effects, while M1, a mitochondria fusion promoter, substantially enhances axonal growth velocity, emphasizing the potential of mitochondria dynamics as a target for improving nerve regeneration. The PNI chip represents a breakthrough in peripheral nerve regeneration research, offering the means to systematically explore nanofiber parameters and drug interventions in a controlled and high-throughput manner.