2017 年 12 巻 1 号 p. 16-00613
Cell migration is an important process both in physiological and pathological conditions. Migrating cells in vivo respond to various extracellular environmental factors and change their migratory behavior. Thus, it is important to take into account extracellular environmental factors in studies on cell migration. This study specifically focused on fibroblast migration in a three-dimensional microenvironment. We fabricated a polydimethylsiloxane cell culture substrate with intersecting grooves as a model to mimic a feature of the complex porous microenvironment experienced by fibroblasts in vivo. The sizes of the grooves allowed fibroblasts to penetrate into the grooves. The effects of branched grooved structures on cell migration, and on cellular organization of the actin filaments and phosphorylated myosin light chain, were analyzed. Fibroblasts migrated along intersecting lattice grooves that were 5 μm wide, 13 μm deep, and spaced 10 μm apart. Analysis of the cellular distribution of actin filaments and phosphorylated myosin light chain demonstrated two effects of the intersecting grooved structure on actin cytoskeletal organization in the fibroblast. One was the enhancement of filopodia protrusions into the branched groove at the junction, and the other was the formation of stress fibers to cross the opening of the junction. These results suggest that the filopodia protrusions are guided by the groove and are followed by the cytoplasmic protrusion, then the rear of the cell retracts due to stress fiber contraction, leading to fibroblast guided migration in the branched intersecting groove.