A closer look at hard-to-see cells could answer new questions about nerve damage and recovery

This article has been reviewed according to Science X's editorial process and policies. Editors have highlighted the following attributes while ensuring the content's credibility: Under the microscope, mitochondria inside healthy terminal Schwann cells form a web of interconnected branches, with tiny doughnut-shaped loops appearing near where the cells branch and split. But getting that view presents a challenge.

Terminal Schwann cells—which help maintain and repair the connections between nerves and muscles—can begin changing shape the moment they are removed from their natural environment. That makes it difficult for scientists to study intracellular components as they would be in the body. New research from Texas A&M University offers a way to get that closer look.

Published in the Journal of Visualized Experiments, the study outlines a method for imaging and evaluating mitochondria inside terminal Schwann cells while preserving their natural structure. This technique gives researchers a new tool for investigating how these cells respond to nerve injury, disease and recovery. "If you want to take a look at the things inside of them, as they are in the body, then somehow you have to image them without them knowing anything is disrupted," said Dr.

Aaron Morton, an assistant professor in Texas A&M's Department of Kinesiology and Sport Management. To explain the role of Schwann cells, Morton compares nerves to electrical wires. A nerve is like the copper wire carrying the signal, while Schwann cells act like the plastic coating around it, providing insulation.

But damage the wire, and the Schwann cells take on a different job. After a nerve injury, Morton said, Schwann cells can change shape and move into the damaged area, where they help clear debris and release growth factors that support healing. The cells then "hold hands," as Morton describes it, forming a pathway that guides the regenerating nerve.

Terminal Schwann cells are found at the neuromuscular junction—the point where a nerve communicates with a muscle. Normally, Morton said, they have a distinctive shape roughly resembling a pretzel. But when they sense injury or disruption, they can lose that structure, "turn into spheres" and begin moving around.