Fig. 3. Expression of neural marker proteins by the clone-growing cells after 4 days of treatment with retinoic acid. (A,B) Double immunostaining for the presence of ß-tubulin III (FITC-conjugated secondary antibody) and GFAP or GalC (Texas-Red-conjugated secondary antibodies). Cells derived from the same clone can express neuronal and astroglial (A) or neuronal and oligodendroglial (B) markers. All cell nuclei were additionally stained with Hoechst 33258. Bar, 50 µM. (C) Western blots of the untreated (RA-) controls and the RA-treated (RA+) differentiated cells probed with anti-ß-tubulin III (neuronal marker), anti-GFAP (astrocytic marker) and anti-PLP/DM-20 (oligodendrocytic marker). The position of the PLP splicing variant, DM-20, is marked by arrow.