Directed cell migration in co-cultures by topographic curvature for heterogeneous tissue engineering

Placing cells in the proper position is important for tissue engineering. Previous works addressed this subject in the way of controlling cell migration by micro- or nano-patterning the substrates. However, the problem of changing spatial cell density freely under co-culture conditions is remaining. To solve this problem, in this work, we report that C2C12 spatial cell density changes by the patterning geometric boundary of the topographical structures. In 48 h after seeding cells, at the linear boundary (ridge-groove) structures, C2C12 Groove/Ridge ratio was under 0.70 both under monoculture conditions and under co-culture conditions. In contrast, at the combining the linear boundary and the round boundary (ridge-groove + hole) structures, the ratio was over 0.89 under both culture conditions. This our finding will provide a new device which enables to manipulate spatial cell density under co-culture conditions for heterogeneous tissue engineering.