Early decrease in hyaluronidase-sensitive cell surface charge during the differentiation of Friend erythroleukemic cells by dimethyl sulfoxide

Early membrane events in erythroid differentiation were investigated by means of cell electrophoresis utilizing cultured Friend erythroleukemia cell clones of different inducibility. The cell electrophoretic mobility decreased by 18% within 30 min of treatment with 1.5% dimethyl sulfoxide (DMSO) in highly inducible clones but not in noninducible clones. The reduced mobility persisted for 5 days of incubation with DMSO until hemoglobin synthesis. DMSO treatment for less than 16 hr and subsequent incubation without the drug resulted in the complete recovery of the mobility and no hemoglobin synthesis. Longer exposure to DMSO resulted in the loss of recovery of mobility and an increasing fraction of benzidine-positive cells seen on Day 5. Measurement of the electrophoretic mobility after the removal of acidic sugars by their specific enzymes suggested that hyaluronidase-sensitive negative charges were lost from the cell surface only in highly inducible clones. The mobility reduction associated with hyaluronic acid was also caused by other potent inducers (sodium butyrate, N-methylacetamide, and N,N-dimethylacetamide). These results suggest that the decrease in cell surface glycocalyx might be an early step in the induction of differentiation of Friend erythroleukemia cells.