Figure 1.

OPCs Lose Their Inherent Capacity for Differentiation and Their Responsiveness to Differentiation Factors with Aging

(A) Representative images of young adult (2–3 months old) and aged OPCs (20–24 months old) differentiated in the absence of growth factor or in the presence of T3. Increasing maturity was visualized using O4 (early), CNPase (intermediate), and MBP (mature), immunocytochemical markers of the oligodendrocyte (OL) lineage. Scale bars, 50 μm.

(B and C) Quantification of cells over time in culture: CNPase⁺/Olig2⁺ cells (B) and MBP⁺/Olig2⁺ cells (C). Statistical significance was determined using two-way ANOVA repeated measurements followed by Dunnett’s post test to compare each group against “aged T3.” All data are presented as mean ± SD (n = 3 biological repeats).

(D) Schematic of the experimental design.

(E) Representative images of the differentiation assay performed with young and aged OPCs. Newly formed oligodendrocytes were identified as MBP⁺/Olig2⁺ cells. Scale bars, 50 μm.

(F and G) Quantification of the differentiation assay for young (F) and aged OPCs (G). n = 3 biological replicates for each group, one-way ANOVA with Dunnett’s multiple comparisons test for each group against the group differentiating in the absence of growth factors (“w/o GF”).

Error bars represent SDs. ^∗p < 0.05, ^∗∗p < 0.01, ^∗∗∗p < 0.001.

See also Figures S1–S3.