Cell subsets have been discriminated in cell
suspensions derived from 37 human head and neck
tumors by means of light scatter,
DNA, and
cytokeratin flow cytometry (FCM). Cell dispersion was performed overnight at 4 degrees C in two different
enzyme mixtures, i.e.,
trypsin/
dithioerythritol and
collagenase/
DNase, under slight agitation of sliced
tumor tissue. Cells were examined before and after fractionation on a discontinuous low-density
bovine serum albumin (BSA) gradient. Forward and right-angle light scatter FCM of 23
tumor specimens revealed four main subpopulations with different size and structure. Fractionation of primary cell
suspensions on a BSA gradient at unit gravity separated debris, small cells and large cells.
DNA FCM of the enriched populations demonstrated a relation between large cells and
DNA aneuploidy. Epithelial cells, as recognized by
cytokeratin antibodies, were also related with large cells. The results demonstrated the usefulness of light scatter,
DNA, and
cytokeratin analysis of crude and fractionated
tumor cell
suspensions for assessment of the efficacy of a particular dispersion technique and to obtain information of the cell subsets dispersed.