Flow cytometric analysis of chromosome damage after irradiation: Relation to chromosome aberrations and cell survival

Reproductive death of cultured cells is commonly assessed by measurement of clonogenic capacity which requires a culture period equivalent to about ten cell doubling times. Chromosome structural changes can be observed microscopically in stained preparations of mitotic cells but this requires tedious counting. For a rapid determination of cellular sensitivity which might provide predictions of responses of tumors to various treatments, a new technique would be valuable if the dependence of responses on dose and radiation quality would correlate well with other cellular responses. Flow cytometry has provided a technique for the rapid determination of DNA content of individual chromosomes of mammalian cells and of changes induced by various treatments. This technique involves selection of mitotic cells, the preparation of mono-disperse chromosome suspensions, measurement of DNA content histograms and the analysis of these histograms by a computer program