Isolation of single cell nuclei from human epidermis for cytophotometric DNA--measurements.

Diluted acetic acid was applied to dissociate human epidermis into its constituents. A simple procedure to gain isolated single cells for cytophometric determination of their nuclear DNA content is described. The method is suited for single cell cytophotometric measurements and for cytofluorimetric flow systems likewise. The losses of Feulgen--stainable nuclear DNA during preparation were studied in dependence on the incubation time of the cells in acetic acid. The kinetics of extraction of nuclear DNA by diluted acetic acid follow a reaction of the first order. It was possible therefore to formulate a simple mathematical correaction for the losses during the isolation of epidermal cells. Avoiding the disadvantage of cut nuclei in histological sections the method is used to study the DNA histograms of resting, regenerating and pathologically altered human epidermis.