Schwann's Cell

Schwann’s Cell


a cell of nerve tissue forming the membranes of the long processes of the nerve cells (axons) in the peripheral nerves and ganglia; first described by T. Schwann in 1838.

The nucleus of a Schwann’s cell is oval and contains one or two nucleoli. Masses of chromatin are found on the inner surface of the nuclear membrane. Mitochondria, lysosomes, the Golgi complex, microtubules, microfibrils, free ribosomes, and ribosomes attached to the membranes are concentrated around the nucleus in the cytoplasm. Schwann’s cells may have cilia. They act as supporting cells in the processes of nerve cells and help form (and in unusual cases destroy) myelin in the medullated fibers. Metabolites penetrate the process of a nerve cell through the substance of Schwann’s cells or at the point where the cells meet. It is possible that some substances are formed in Schwann’s cells and then proceed to the processes. The capacity of Schwann’s cells for wave like movements may be related to the transport of various substances along the processes of nerve cells.

References in periodicals archive ?
Beginning with the 1838 Schleiden and Schwann's cell theory stated that the cell was the basic unit of life, it was then realized that a cell is capable of autonomy and totipotent, or a cell can give rise to the whole organism.
1-7) They are generally solitary and they can occur along any somatic or sympathetic nerve in the body except the olfactory and optic nerves, which lack Schwann's cell sheaths and which are part of the central nervous system.
16] Similarly, granular cell tumors cytoplasmically stain for S-100 protein, are closely associated with nerves, and are often present in distal nerve trunks; all of these characteristics support a Schwann's cell origin.
Granular cell tumors are relatively uncommon soft tissue lesions that originate in Schwann's cells.
They are believed to originate in the ectodermal Schwann's cells of the nerve sheath.
They can arise in all peripheral nerve elements, including Schwann's cells, neurons, fibroblasts, and perineural cells.
Neurilemmomas are peripheral nerve sheath tumors derived from Schwann's cells.
2) Malignant peripheral nerve sheath tumor can originate in any cell of the nerve sheath, including Schwann's cells and fibroblasts that surround motor and sensory nerve axons.
Schwannomas arise from neural crest-derived Schwann's cells; they can originate in any peripheral or cranial nerve except the olfactory and optic nerves, which lack Schwann's cells.
Malignant peripheral nerve sheath tumor--also known as neurogenic sarcoma, malignant neurilemoma, malignant schwannoma, and neurofibrosarcoma--is an uncommon neoplasm that originates in Schwann's cells of the nerve sheath.
4) Neuromas are uncommon benign parotid tumors; they include schwannomas (neurilemmomas) and neurofibromas, although both originate in Schwann's cells.
Schwann's cells have often been identified as the cells of origin.