Features independent of stain intensity for evaluating Feulgen-stained cells.

Eleven features that are independent of stain intensity are described. Values greater than 1.4 times the average optical density were shown to define the visually darker areas of the image, which were considered to be condensed chromatin. Use of the 11 features permitted the discrimination between (1) lymphocytes and macrophages of rats, (2) macrophages from the spleens of rats and monocytes from peripheral blood and (3) macrophages from the spleens of rats injected with complete Freund's adjuvant and those from the spleens of normal rats.