What is the role of Schwann cells in the nervous system?

Schwann cells play a crucial role in the nervous system by producing the myelin sheath that insulates nerve fibres.

Schwann cells are a type of glial cell found in the peripheral nervous system. Their primary function is to produce myelin, a fatty substance that wraps around the axons of neurons. This myelin sheath acts as an insulator, increasing the speed at which electrical impulses, or action potentials, travel along the nerve fibre. This is essential for the efficient functioning of the nervous system, as it allows for rapid communication between different parts of the body.

Schwann cells are also involved in the repair and regeneration of damaged nerves. When a nerve fibre is damaged, the Schwann cells surrounding it divide and form a tube, which guides the growth of a new nerve fibre. This is a unique feature of the peripheral nervous system; in the central nervous system, which includes the brain and spinal cord, damaged nerve fibres cannot regenerate in the same way.

In addition to these roles, recent research has suggested that Schwann cells may also play a role in modulating immune responses and maintaining homeostasis in the nervous system. They can secrete various factors that influence the activity of immune cells, and may also help to protect neurons from damage during inflammation or infection.

In summary, Schwann cells are vital for the normal functioning of the nervous system. They produce the myelin sheath that insulates nerve fibres, increasing the speed of electrical impulses and enabling rapid communication between different parts of the body. They also play a role in nerve repair and regeneration, and may contribute to immune regulation and homeostasis in the nervous system.