Fig. 8

IRX4204 stimulates differentiation of primary rat OPCs in vitro. (A–J) Representative images of overlain MBP and Hoechst immunofluorescence in OPC cultures. One day following isolation and plating, OPCs were treated with increasing concentrations of IRX4204 for either 24 h (DIV 2; A, C, E, G, I) or 5 days in vitro (DIV 6; B, D, F, H, J). (K–N) Proportion of MBP-positive cells to DAPI-positive cells (K and L) and number of DAPI-positive cells per mm² (M and N) after 24 h or 5 days of treatment with increasing concentrations of IRX4204. After 24 h treatment, 10 nM of IRX4204 significantly increased the fraction of MBP immunopositive cells, without altering the total number of cells. After 5 days of treatment, the fraction of MBP immunopositive cells increased with IRX4204 treatment, with a statistically significant increase detected for a concentration of 1 nM IRX4204 (n = 14–16 fields/condition; non-parametric Kruskal-Wallis test, Dunn’s multiple comparisons test, *P < 0.05, mean ± SEM; scale bar 50 μm)