The kinetics of contact inhibition in mammalian cells

To elucidate the process of contact inhibition in mammalian cells, we investigated the kinetics of growth arrest in [3H]thymidine labelled embryonic chinese hamster (Cricetulus griseus L.) cells after the addition of various concentrations of unlabelled cells. It was observed that after the contact inhibition concentration had been reached, the cells grew undisturbed for one more generation. In the following 24 hr the concentration fell back to the level at the beginning of the experiment and stayed there.