Mitogen-induced changes in sialyltransferase activity in human normal and leukemic lymphocytes.
Phytohemagglutinin-P (PHA-P) and concanavalin A (Con A) induced an increase in sialyltransferase (S-T) activity of the blood lymphocytes within 24 hours. PHA-P induced the maximal increase in S-T activity in the lymphocytes at 10 micrograms/ml and with Con A at 5 micrograms/ml. PHA-P induced a greater response than that by Con A. An additional effect of these mitogens was not observed. The exposure of cell extracts to these mitogens did not induce the increase in S-T activity. PHA-P or Con A had no effect on the induction of terminal deoxynucleotidyl transferase (TdT) activity, TdT-positive cells or peanut agglutinin (PNA)-positive cells from blood lymphocytes. Therefore, the change of the lymphocytes induced by these mitogens does not indicate a reversion to more immature state of lymphocyte differentiation, but represents a process of the functional differentiation to more activated lymphocytes. These mitogens had only a slight effect on S-T activity of human T-lymphoid leukemia cell lines. The decreased effects of the mitogens on S-T activity of leukemic cells may reflect the change of the membranes due to malignant transformation or the incomplete membrane structure in undifferentiated leukemic cells.
Sasaki
R
R
Takaku
F
F
Miura
Y
Y
D002460:Cell Line; D003208:Concanavalin A / Q000494:pharmacology; D004253:DNA Nucleotidylexotransferase / Q000097:blood; D006801:Humans; D066298:In Vitro Techniques; D007945:Leukemia, Lymphoid / Q000201:enzymology*; D008214:Lymphocytes / Q000201:enzymology*; D008934:Mitogens / Q000494:pharmacology*; D010835:Phytohemagglutinins / Q000494:pharmacology; D012799:Sialyltransferases / Q000097:blood*; D014166:Transferases / Q000097:blood*; D000094802:beta-D-Galactoside alpha 2-6-Sialyltransferase
D008934:Mitogens; D010835:Phytohemagglutinins; C028784:phytohemagglutinin-P; D003208:Concanavalin A; D014166:Transferases; D012799:Sialyltransferases; D004253:DNA Nucleotidylexotransferase; D000094802:beta-D-Galactoside alpha 2-6-Sialyltransferase