title: G-CSF accelerates the cell-cycling of hematopoietic progenitor cells and abrogates the deceleration by TNF alpha.
abstract: We examined the effects of granulocyte colony-stimulating factor (G-CSF) on cell-cycling of hematopoietic progenitors in serum-free methylcellulose clonal cultures. Serial observations of the cultures showed hastening of growth of colonies by G-CSF, as determined by evaluating the time for individual colonies of 20 cells to reach 40 cells. G-CSF did not affect the incidence of proliferating cells in each developing colony. Cell-cycle analysis revealed that addition of G-CSF to cultures led to a decrease in the percentage of cells in the G1 phase of the cell-cycle, thereby indicating that G-CSF can modulate the cell-cycle of hematopoietic progenitors mainly by shortening the period of the G1 phase. Tumor necrosis factor alpha (TNF alpha) exerted opposite effects on cell-cycling of hematopoietic progenitors to those seen with G-CSF. G-CSF abolished the inhibitory effects of TNF alpha on the cell-cycling of hematopoietic progenitors. These observations indicate positive and negative regulatory roles of C-CSF and TNF alpha, respectively, and their interactions in the regulation of cell-cycling of hematopoietic progenitors.
authors.affiliation: MIE UNIV,SCH MED,DEPT INTERNAL MED 2,TSU,MIE 514,JAPAN. MIE UNIV HOSP,BLOOD TRANSFUS SERV,TSU,MIE 514,JAPAN.
authors.forename: N
authors.initials: N
authors.lastname: Mahmud
authors.forename: N
authors.initials: N
authors.lastname: Katayama
authors.forename: R
authors.initials: R
authors.lastname: Itoh
authors.forename: K
authors.initials: K
authors.lastname: Ohishi
authors.forename: M
authors.initials: M
authors.lastname: Masuya
authors.forename: N
authors.initials: N
authors.lastname: Minami
authors.forename: H
authors.initials: H
authors.lastname: Shiku