FIG. 6.

Directed differentiation of MSCs into juxtaposed cartilage and bone using segregated morphogen fields. (A) Schematic of scaffold dimensions and contents (left) and orientation of scaffolds for subsequent analysis (right). (B) Representative photograph of a 1-mm-thick section from scaffolds after fixation and dual staining with Alcian Blue and Alizarin Red. (C) Scanning electron micrograph (left) and inset area (middle) showing localized electron-dense precipitates on the 1-mm-thick section from scaffolds. Energy-dispersive X-ray spectroscopic analysis identified mineralized precipitates to comprise antimonate (right). (D) Scaffolds were dissected into three zones, homogenized, and analyzed by western blotting for production of aggrecan (AGG), type II collagen (Col-II), bone sialoprotein II (BSP-II), osteopontin (OPN), and type X collagen (Col-X). β-Actin was used as a loading control. Representative western blots (left) and quantification of integrated band density (right) are shown (n=5). Asterisks indicate statistical significance at p<0.05. Color images available online at www.liebertpub.com/tea