A simple method for analysis of DNA histograms in human myeloid cells perturbed by stimulators of DNA synthesis

In the past, phase fractionation has been used as a determinate of the level of stimulation of cells perturbed by stimulators and inhibitors of DNA synthesis. This method has, in our hands, proven to be insensitive and unreliable with human myeloid cells. A new method of analysis is described in this paper which involves utilization of the magnitude of the slope of a line fit to the mid-portion of S phase as an index of the level of stimulation of cultured human myeloid cells. This method is fast, reliable and simple to implement on an inexpensive microcomputer.