The Kinetics of Cell Proliferation in Cultures of Human Peripheral Blood

The kinetics of growth of peripheral blood cells in tissue culture are described. There was a rapid increase of cells in DNA synthesis beginning at 24 hours and by 72 hours 40-45 per cent of the cells were in DNA synthesis. Mitotic rates of ∼ 1 per cent/hour were seen after 72 hours in cultures. Studies with tritiated thymidine and colchicine indicated that these cells represent transformed lymphocytes and do not arise from the cells in DNA synthesis at time zero or from any other small population of cells.