Fig. 8. Chondrogenic cells isolated from EBs were kept in a dedifferentiated state by treatment with TGF-ß3. After 8 days in culture, initially dedifferentiated chondrogenic cells isolated from EBs formed cell condensations (A) and showed expression of collagen II (B) but only trace amounts of collagen I (C) as demonstrated by immunostaining. Treatment with TGF-ß3 with either 10 ng/ml (D-F) or 50 ng/ml (G-I) resulted in inhibition of cell condensations (D,G) and collagen II expression (E,H) but increased expression of collagen I (F,I). Representative areas are shown. Bar, 100 µm.