Figure 3.

ALK3^CA gene transduction increases Alcian blue–positive matrix and type II collagen deposition in pellet cultures of SFs. (A–J) Adenovirus–infected SF pellets were fixed with 3.7% formaldehyde after 3 weeks of culture and then were subjected to Alcian blue staining (A, D, G, and I) or immunostaining with anti–type II collagen (B, E, H, and J) or anti–type X collagen (Col X) (C and F). Distinct Alcian blue (D) and type II collagen (E) staining was observed in ALK3^CA-expressing cultures. ALK6^CA-expressing cultures showed weaker staining (I and J), and no positive staining was observed in ALK5^CA virus–infected (G and H) or LacZ virus–infected (A and B) cultures. No type X collagen immunostaining was observed in cultures expressing LacZ or ALK3^CA (C and F). Scale bar: 100 μm.