Comparison of message levels of col1a1, col3a1, TGF-β, and α-SMA for cells seeded in released gels cultured in M199 between serum levels (5 and 10% FBS) for time points 6-120 h. Col1a1 (panel A) expression significantly decreased, while col3a1 (panel B) significantly increased over time, although there were no differences in response to FBS levels. For cells cultured in 5% FBS, significantly higher TGF-β expression (panel C) occurred at the 24 hour point compared to other time points. A spike in TFG-β expression also was observed at 24 hrs with 10% FBS, although this increase was significantly less than that observed with 5% FBS. A biphasic change in α-SMA (panel D) expression was observed with both serum levels, with an initial decrease, followed by a return toward the 6 hr level after 24 hours. Significant differences were determined using ANOVA and p<0.05 (*) considered significantly different using a post-hoc Tukey multiple comparison tests.