(a–c) Real-time RT-PCR analyses of mRNA transcript levels of contractile markers (α-SMA and SM22α) in synthetic (SYN) and TGF-β1-treated constructs seeded with SMC lines. Levels normalized to GAPDH expression. Mean ± SD per data point. For each marker, *p < 0.05, in comparison to levels in respective SYN controls. (a′–c′) Photomicrographs of contractile protein expression in TGF-β1-treated constructs as described in respective (a–c) counterparts. In vitro evaluation of bi-layer silk fibroin scaffolds for gastrointestinal tissue engineering: Franck D, Chung YG, Coburn J, Kaplan DL, Estrada CR, Mauney JR - Journal of tissue engineering (2014). Not altered. CC.