FIG. 4.

(A) Cross-sectional area (CSA) analysis of construct morphology indicates that after 30 days in vivo, the SMUs developed small but defined muscle fibers. (B) The construct fibers featured laminin-rich extracellular matrices (Laminin, green) and expressed myosin heavy chain (MF-20, red). (C) Analysis of the CSAs of the construct (n=6 constructs) and native control TA (n=8) fibers indicates that the construct fibers' average CSA is 118±6 μm², or 8.0% of the average CSA of the native fibers in the control TAs (p<0.0001). (D) Staining for fibroblast specific protein 1 (FSP1, green) indicates that the numerous cells near the graft muscle fibers (MF-20, red) are fibroblasts. Error bars indicate standard error. ^†Statistical difference from the native muscle fibers. Color images available online at www.liebertpub.com/tea