Cell kinetics of the K‐562 cell line in microculture

The cell kinetic parameters of K‐562 leukemia cells were studied using microwell cultures in which growth was initiated from a single cell. Total population growth was studied by direct enumeration, ³H‐thymidine labelling, and flow cytometry. Clonogenic cell growth was studied by replating and ³H‐thymidine suicide. In 7‐day clones of K‐562 cells, durations of the total cell cycle, G1, S, G2, and M phases were 20.8 h, 3.5 h, 12.9 h, 3.3 h, and 1.1 h, respectively; the growth fraction was 0.92 and the cell loss factor was 0.084. Study of colony‐forming cells by replating indicated that clonogenic cells comprised 40% of total cells. ³H‐Thymidine suicide showed that cell‐cycle duration for these cells was 22.5 h and that S‐phase duration was 11.7 h.