The Automatic Analysis of Flm Curves

Abstract. Seven parameters of the cell cycle are extracted from experimental FLM data by computer using a completely automated, least-squares, regression analysis. the procedure is based on a model of the cell cycle with four phases, three coefficients of variation, and a Poisson process of cell progression. T _M is estimated separately, using mitoses per labeled cells over the first cycle. Beginning with raw data, the computer calculates initial estimates of the parameters, uses these estimates to generate a synthetic FLM curve, and then measures a weighted mean square deviation of fit between the data and the curve. By a process of iteration, involving a three-dimensional Newton-Raphson method for mean transit times and an orthogonal search for coefficients of variation, the measure of fit is progressively minimized. Eighteen experimental data sets have been analysed successfully. Several procedures for the evaluation of the analysis are described.