Fig. 10. Terminal differentiation of oligodendrocytes in Sox10^K2/K2 and Sox10^aa1/aa1 embryos. (A) In situ hybridizations with probes specific for Plp and Mbp were performed on transverse spinal cord sections from the forelimb region of wild-type, Sox10^K2/K2 and Sox10^aa1/aa1 mouse embryos at 18.5 dpc. (B) Plp-positive (black bars) and Mbp-positive (gray bars) cells were counted on at least 20 sections from three independent embryos for wild-type and Sox10^K2/K2 spinal cords. The number of cells counted in the wild type was set to 100%. Cell numbers for the Sox10^K2/K2 are presented relative to the wild type as mean±s.d. Statistically significant differences were observed using Student's t-test for Plp (P0.001) and Mbp (P0.01). (C) Similar quantifications for Sox10^aa1/aa1. No statistical difference in the number of Plp- and Mbp-positive cells was detected compared with the wild type.