 The PSA-expressing Schwann cells were able to myelinate CNS axons in cerebellar slices, which is not normally possible "in vivo".It is hopeful that these PSA-expressing Schwann cells will be able to migrate throughout the CNS without loss of myelinating abilities and may become useful for regeneration and myelination of axons in the central nervous system.Astrocytes are glial cells that are abundant in the central nervous system.