Oligodendrocyte (OL) progenitor cells (OPCs) give rise to the myelinating cells of the central nervous system (CNS), the OL. To examine molecular changes involved in OPC differentiation, a microarray analysis was performed at several time points during OPC maturation. The results revealed significant expression levels of mRNA for reelin, one reelin receptor, very low density lipoprotein receptor (Vldlr), and the cytoplasmic adaptor molecule, disabled homolog 1 (Dab1). The expression of these proteins in oligodendroglial (ODG) cells was confirmed by immunocytochemistry and Western blot analysis. It was also discovered that both progenitors and mature OLs secrete reelin. Although there is no known effect of reelin on ODG cells, the data suggest that these cells may be a source of reelin in the CNS. Anat Rec, 2011. © 2011 Wiley-Liss, Inc.