Lab-grown nerves match human sensory signal speeds, enabling tests of myelin repair

Researchers from Rice University and ETH Zurich have created a platform to cultivate human nerve cells and Schwann cells, which help form the protective myelin coating around nerve fibers. This innovative system allows for the development of functional myelin within a three-dimensional environment. The study, published in Advanced Healthcare Materials, demonstrates that myelin forms effectively and alters the speed at which electrical signals travel across nerve cell networks.

The platform combines human-derived cells, tissue-like materials, and electrical measurements. This unique approach enables researchers to study myelin development, injury effects, and potential therapies for myelin repair. The platform's adaptability allows it to model the brain and measure complex cellular processes.

The team chose to grow human sensory neurons in hydrogels, soft water-rich materials whose stiffness can be tailored to mimic the properties of biological tissues. By surrounding the neurons with Schwann cells, the researchers observed that electrical signals traveled faster, confirming that the myelin was functional. This finding is significant as it indicates that the conduction velocities measured were similar to those found in human sensory nerves.

The hydrogel-based microfluidic device, called hydroMEA, allows for precise control over cell arrangement while maintaining a three-dimensional growth environment. By imaging the system, researchers confirmed that myelin had formed around nerve fibers. The combination of visual confirmation and electrical measurements provides a comprehensive understanding of nerve function and myelin's role in maintaining signal speed.