Schwann cells don caps, touch nodes n vertebrates, axons are covered with an insulating myelin sheath, punctuated by gaps called nodes of Ranvier where voltage-gated sodium channels cluster. The nodes are essential for propagating action potentials along the axon, but little is known about how they develop. Gatto et al. (page 489) imaged live cell cultures to watch Schwann cells myelinate expla...

The specific axonal and Schwann cell surface molecules that mediate the initiation of myelination have not been identified. We have used cocultures of purified rat dorsal root ganglion neurons and Schwann cells and purified polyclonal antibodies to the L1 adhesion molecule to study the role of L1 in myelin formation. Schwann cells were first arrested in a basal-lamina-free premyelination stage ...

Previous studies (Blank, W. F., M. B. Bunge, and R. P. Bunge. 1974. Brain Res. 67:503-518) showed that Schwann cell paranodal membranes were disrupted in calcium free medium suggesting that cadherin mediated mechanisms may operate to maintain the integrity of the paranodal membrane complex. Using antibodies against the fifth extracellular domain of E-cadherin, we now show by confocal laser and ...

Schwann cells exhibit a high degree of plasticity in adult peripheral nerves after mechanical injury; they have, therefore, been implicated in promoting nerve regeneration. However, Schwann cell behavior after ischemic injury has not yet been elucidated. To determine how Schwann cell plasticity may contribute to recovery from ischemic neuropathy, we used a rat model in which ischemia was induce...

Schwann cells express low levels of myelin proteins in the absence of neurons. When Schwann cells and neurons are cultured together the production of myelin proteins is elevated, and myelin is formed. For peripheral myelin protein 22 (PMP22), the exact amount of protein produced is critical, because peripheral neuropathies result from its underexpression or overexpression. In this study we exam...

Mechanisms regulating Schwann cell differentiation into a myelinating or a mature nonmyelinating phenotype during development are poorly understood. Humoral factors such as members of the transforming growth factor-beta (TGF-beta) family, which are found in the developing and adult mammalian nervous system and are known to affect cell differentiation, could be involved. We tested the effects of...

Neurofibromatosis type 1 (NF1) patients develop neurofibromas, tumors of Schwann cell origin, as a result of loss of the Ras-GAP neurofibromin. In normal nerves, Schwann cells are found tightly associated with axons, while loss of axonal contact is a frequent and important early event in neurofibroma development. However, the molecular basis of this physical interaction or how it is disrupted i...

The expression of the 330 kDa AN2 glycoprotein was studied in the rodent peripheral nervous system. AN2 is expressed by immature Schwann cells in vitro and in vivo and downregulated as the cells upregulate myelin genes. A subpopulation of nonmyelinating Schwann cells in the adult sciatic nerve retains expression of AN2. In rat sciatic nerve crushes, where Schwann cell numbers increase after ini...

PURPOSE OF REVIEW To describe the current status of testing Schwann cell transplantation as a therapy for human spinal cord injury (SCI). RECENT FINDINGS Transplanted Schwann cells have reparative effects in the damaged spinal cord. A few clinical studies have reported that Schwann cell transplantation appears safe. Compared with allogeneic cell transplants, autologous cells do not require im...

Neuroblastoma (NB), a common pediatric neoplasm, consists of two main cell populations: neuroblastic/ganglionic cells and Schwann cells. NB tumors with abundant Schwannian stroma display a more benign clinical behavior than stroma-poor tumors. Recent studies suggest that Schwann cells influence NB tumor growth via secreted factors that induce differentiation, suppress proliferation, and inhibit...