Effects of cytochalasin B on cell to cell adhesion and cellular shape of embryo mesoderm cells in vitro.

The effects of cytochalasin B on chick embryo mesoderm cells cultured in vitro were studied by scanning electron microscopy. The untreated cells showed numerous filopodia and lamellipodia and they were flattened onto the coverslip. Several cellular clusters were observed in each culture. The treated cells did not show filopodia, they had a rounded shape and cellular clusters were not present on the coverslip. These alterations are discussed on the basis of the actions of cytochalasin B on the micrcfilamentous cytoskeleton and the role proposed for microfilaments in filopodia formation, cellular shape and locomotion. It was observed that the mechanisms of cell to cell adhesion of chick embryo mesoderm cells were not the same as the mechanisms of cell adhesion to artificial substrates.