The influence of serum-free culture conditions on skeletal muscle differentiation in a tissue-engineered model.

The influence of differentiation medium (DM) components on C2C12 murine myoblast differentiation has only been studied in monolayer cultures. Serum-free formulations have been applied that omit the use of sera with unknown composition. The goal of the present study was to compare the influence of serum-free media on C2C12 differentiation in 3-dimensional tissue-engineered muscle constructs. Myoblast proliferation and differentiation in media containing Ultroser G (DMU), insulin-like growth factor (IGF)-I (DMI), or both (DMUI) were compared with those induced by more-traditional media containing horse serum (HS) or horse serum and IGF-I (HSI). Effects of the applied media were assessed from gross construct morphology, total protein content, creatine kinase activity, and tissue viability. Addition of IGF-I (HSI) to the standard DM (HS) improved myoblast differentiation in muscle constructs. Even better results were obtained using DMU and DMUI culture conditions. DMI could not induce differentiation or maintain cell viability. Serum-free culture medium supplemented with DMU or DMUI accelerates and improves myoblast differentiation in engineered muscle tissue better than the gold standard HS.