Role of carbohydrate moiety in granulocyte colony stimulating factor

Biological activities of two granulocyte-colony stimulating factor (G-CSF) preparations with (Lenograstim) or without (Filgrastim) sugar moiety were compared. Both G-CSF preparations similarly enhanced the N-Formyl-Met-Leu-Phe-induced-migration of human peripheral blood polymorphonuclear cells, but did not significantly affect the proliferation of human oral tumor cell lines (HSC-2, HSG). However, Lenograstim induced cytotoxicity (accompanied by the production of cytoplasmic vacuoles and large DNA fragments) in human promyelocytic leukemic cells HL-60, more potently than Filgrastim. Lenograstim, but not Filgrastim, enhanced the cytotoxic activity of sodium ascorbate. In contrast to Lenograstim, Filgrastim was degraded gradually, but too slowly to explain its lower biological activity. These data suggest that the carbohydrate moiety in G-CSF might confer unique biological activities.