Flow cytometry is used for the counting, sizing, and biochemical characterization of single cells and has become increasingly important in cell biology in general and in studies of cellular immunity and cancer in particular. The complexity and cost of the most modern apparatus have restricted the range of experimental and clinical applications of the technique. A new instrument design employing optical waveguides in place of lenses for illumination and collection, and utilizing low-power laser light sources, will be compared with existing apparatus in analyses of DNA and RNA content and antigen expression in cultured eukaryotic cells. New fluorescent stains and light sources will be examined for possible advantages for such analyses. Low-power helium-cadmium laser sources will be evaluated for bivariate flow cytometric analysis of isolated chromosomes.
