New oligodendrocytes exhibit more abundant and accurate myelin regeneration than those that survive demyelination

Oligodendrocytes that survive demyelination can remyelinate, including in Multiple Sclerosis (MS), but how they do so is unclear. Here, using zebrafish, we found that surviving oligodendrocytes make few new sheaths and frequently mistarget new myelin to neuronal cell bodies, a pathology we also found in MS. In contrast, oligodendrocytes generated after demyelination make abundant and correctly targeted sheaths, indicating that they likely also have a better regenerative potential in MS.