(A) Immunostaining for MBP, CC1, NG2, GFAP and Olig2 co-stained with CC1 and PDGFRα within the optic nerves of control (MRFwt/fl; Olig2wt/cre and MRFfl/fl; Olig2wt/wt) and MRF CKO (MRFfl/fl; Olig2wt/cre) mice at P13. Scale bar=50um. (B) Quantification of the density of Olig2 immunopositive nuclei within the optic nerves. (C) Quantification of the density of Olig2+/CC1+ double-immunopositive OLs within the optic nerves. (D) Quantification of the density of Olig2+/PDGFRα+ double-immunopositive OPCs within the optic nerves. All results are expressed as means ±SEM, n=4-5 per genotype. *P<0.05, **P<0.01. (E) Densities of Olig2 immunopositive cells within the optic nerves of each genotype broken down into Olig2+ cells also positive for either CC1 (OLs), PDGFRα (OPCs) or neither marker.