monolayering of cells

Tendency of animal tissue cells growing on solid surfaces to cover the surface with a complete layer only one cell thick, before growing on top of each other. This non-random distribution is generated by contact inhibition of locomotion, a phenomenon in which colliding cells change direction rather than move over one another. Of the theories why some (but by no means all) types of cells stop growing when a monolayer is formed, present evidence favours limitation by supply of growth factors from the medium, rather than any inhibitory effect of contact on growth.