Schwanns

Schwanns is a surname that is most prominently associated with Theodor Schwann (1810–1882), a German physiologist who helped establish cell theory and made foundational contributions to our understanding of the nervous system. In biology, the term Schwann is also attached to Schwann cells, glial cells of the peripheral nervous system named after him. Schwann cells are essential for the formation, maintenance, and function of peripheral nerves.

Schwann cells originate from neural crest cells. In myelinated peripheral nerves, a single Schwann cell wraps around a segment of an axon to form the myelin sheath, which increases the speed of electrical conduction. In unmyelinated fibers, one Schwann cell can ensheath several small axons without producing compact myelin. Schwann cells also provide metabolic and trophic support to axons and participate in the structural organization of nerves.

During development and after injury, Schwann cells play a central role in nerve regeneration. They can dedifferentiate and proliferate, align to form bands of Bungner that guide regrowing axons, and secrete growth factors and extracellular matrix components that promote repair and remyelination. Their plasticity is a key factor in the peripheral nervous system’s relative capacity for regeneration compared with the central nervous system.

Clinically, Schwann cells are the origin of Schwannomas (neurilemmomas), typically benign tumors that arise from nerve sheaths. Vestibular schwannomas affect the eighth cranial nerve and are a classic example of such tumors. Schwann cell biology also features in discussions of inherited neuropathies and demyelinating diseases.