Changes in the uptake of 57Co-cyanocobalamin during dimethylsulphoxide-induced differentiation of HL60 cells to neutrophils.
The uptake of serum-bound 57Co-cyanocobalamin by uninduced and dimethylsulphoxide-induced HL60 cells has been studied. The data indicate that during the maturation of promyelocytes to neutrophil granulocytes, there is a progressive and marked reduction in (a) the number of surface receptors for the transcobalamin II-cobalamin complex (TCII-Cbl) per cell up to the metamyelocyte stage and (b) the amount of TCII-Cbl entering a cell, through the entire maturation pathway. The maturation of promyelocytes to neutrophil granulocytes was also accompanied by a marked reduction in intracellular vitamin B12 content. These observations help in explaining some features of granulocytopoiesis in cobalamin deficiency.
D001692:Biological Transport; D002454:Cell Differentiation / Q000187:drug effects; D002460:Cell Line; D003037:Cobalt Radioisotopes; D004121:Dimethyl Sulfoxide / Q000494:pharmacology*; D006801:Humans; D007700:Kinetics; D015470:Leukemia, Myeloid, Acute / Q000473:pathology*; D009504:Neutrophils / Q000166:cytology*; D013696:Temperature; D014805:Vitamin B 12 / Q000378:metabolism*
D003037:Cobalt Radioisotopes; D014805:Vitamin B 12; D004121:Dimethyl Sulfoxide