High-Speed Cell Analysis and Sorting with Flow Systems: Biological Applications and New Approaches

A brief historical account of cell analysis and sorting by high-speed flow-through methods is presented. The status of the Lawrence Livermore Laboratory program in this area is described, including biological applications such as the measurement of the DNA content of mouse liver cells and cultured mammalian cells. Histograms of cellular DNA content can be analyzed mathematically by means of a least squares fitting code. The usefulness of this procedure in extracting information on the life cycle parameters of growing cells is demonstrated. A simple computer model of cell growth is used to demonstrate the accuracy of the fitting code and to elucidate shifts in the shape of the DNA histogram as a function of the fraction of cells in the DNA synthesis phase. A new electronic cell sorter is described with emphasis on new features that insure simplicity, reliability, ease of operation, flexibility, and efficiency. Future directions of both technological development and biomedical applications are considered.