Chemical carcinogen in vitro testing: a method for sizing cell nuclei in the nuclear enlargement assay.

The observation that cells often respond to carcinogens by nuclear enlargement has suggested that this property might be useful to develop a short-term screening test for such compounds. Previous methods for detecting nuclear size increases have used an image analyzer system to detect nuclear changes in individual cells. This paper details a more rapid method for obtaining nuclei by use of a stromalyzing procedure following by analysis of nuclear volumes, using a Coulter Counter Channelyzer. This new and simplified nuclear sizing method should facilitate the use of the assay as a possible carcinogenesis screen by permitting rapid and efficient testing of large numbers of compounds.