Changes of cytoskeletons in Ito cells during cell culture: with special reference to actin, myosin and desmin

Ito cells (Fat-storing cells) were isolated and cultured. Cytoskeletons, i.e. actin, myosin and desmin, were observed during the course of culture. Ito cells spread on the culture dish, and actin became filamentary, as the stress fiber. Myosin also showed filamentous patterns similar to the stress fiber, and some revealed stripes. Desmin became filamentary and a network was observed in the cytoplasm. When cytochalasin B was added to culture medium, filaments of actin and myosin were transformed into short rods or granules. These findings suggest that Ito cells, during culture, transform in a similar way to fibrogenic cells (fibroblasts), and also maintain characteristics resembling myogenic cells (myoblasts), and that Ito cells are the precursor cells of myofibroblasts.