Cell surface alterations occurred during murine
erythroleukemia cell (clone 745) differentiation that were detected by both agglutination and
lectin binding. Agglutination of
erythroleukemia cells was produced by
wheat germ agglutinin; whereas,
concanavalin A,
Ricin,
soybean agglutinin and
fucose-binding protein were either ineffective or much less efficacious. Treatment of
leukemia cells with the inducer of erythroid differentiation
dimethylsulfoxide (
DMSO) caused a progressive accumulation of
hemoglobin-containing cells in culture and a decrease in the rate of agglutination by
wheat germ agglutinin, which began at 24 h after exposure to the polar
solvent, reached a nadir at 48 h, and remained essentially constant thereafter. The binding of radioactive
wheat germ agglutinin by untreated control
erythroleukemia cells increased with time in culture, reaching a maximum value at 48 h, and decreased progressively thereafter. Although an increase in 3H-labeled
wheat germ agglutinin binding also occurred in
DMSO-treated cells, the level bound was significantly lower than that observed in control cells at 24-96 h. The treatment of
erythroleukemia cells with various concentrations of
DMSO resulted in a decrease in the number of
wheat germ agglutinin receptor sites. Other inducers of differentiation (i.e.,
dimethylformamide,
bis(acetyl)diaminopentane) also inhibited the rate of
wheat germ agglutinin-induced agglutination of
erythroleukemia cells while, in contrast, the inducer
tetramethylurea did not. These studies indicate that membrane changes occur during differentiation and suggest that there may be more than one mechanism involved in the initiation of maturation which ultimately leads to the common pathway of erythroid development.