FIGURE 7.

Exogenous application of rSHH accelerates the chondrogenic program in micromass culture. Addition of rSHH (10 ng/ml) to control micromass cultures resulted in significantly up-regulated expression of Ptc1 and Gli1 at all time points (with the exception of day 2 forelimb cultures) compared with control medium (A and B). Col2a1, Sox9, and aggrecan expression was also up-regulated in the same cultures, as was the hypertrophy marker Col10a1 (C, D, F, and H). The pre-hypertrophic chondrogenic marker Sox5, and osteoblast marker Runx2, showed a consistent elevated response to rSHH by day 6 of culture (E and G). *, p < 0.05. Error bars represent S.D. FL, forelimb; HL, hindlimb.