title: Insulin-like Growth Factor-1 (IGF-1) is a Costimulator of the Expansion of Lineage Committed Cells Derived from Peripheral Blood Mobilized CD34(+) Cells in Multiple Myeloma Patients.
abstract: The effect of insulin-like growth factor-1 (IGF-1) on highly enriched human apheresis CD34(+) progenitor cells was investigated in vitro. The progenitor cells were mobilized by treatment with cyclophosphamide + granulocyte-colony stimulating factor (G-CSF) in patients with multiple myeloma. CD34(+) cells were cultured for 7 days in serumfree medium containing stem cell factor (SCF), granulocyte-macrophage colony stimulating factor (GM-CSF) and interleukin-3 (IL-3), and this is referred to as cytokine-dependent proliferation. After 7 days of cytokine-dependent proliferation the total number of viable cells increased 1.6-8.2 times, and subsets of cells expressing the granulocyte marker CD15, the myelomonocytic marker CD64 and the erythrocyte phenotype CD71(high)/CD64(-) were detected among the in vitro cultured cells. Addition of G-CSF together with SCF + IL-3 + GM-CSF increased the number of CD15(+) and CD64(+) cells, but without altering the number of erythroid cells. IGF-1 caused a dose-dependent increase in the number of CD15(+), CD64(+) and CD71(high)/CD64(-) cells, and this increase was detected when cells were cultured in both SCF + IL-3 + GM-CSF alone and G-CSF + SCF + IL-3 + GM-CSF. A minor subset of CD34(+) cells could still be detected among in vitro cultured cells and the number of CD34(+) cells was not altered by adding G-CSF and/or IGF-1. Morphologically recognizable mature granulocytes or erythroid cells could not be detected for any of the combinations investigated. We conclude that IGF-1 can enhance the in vitro proliferation of committed progenitor cells derived from apheresis CD34(+) cells.
authors.affiliation: a Division for Endocrinology , University of Bergen, Haukeland Hospital , Norway.
authors.forename: S
authors.initials: S
authors.lastname: Frostad
authors.affiliation: b Pediatric Department , University of Bergen, Haukeland Hospital , Norway.
authors.forename: R
authors.initials: R
authors.lastname: Bjerknes
authors.affiliation: c The Blood Bank , University of Bergen, Haukeland Hospital , Norway.
authors.forename: T
authors.initials: T
authors.lastname: Hervig
authors.affiliation: d Division for Hematology, Medical Department B , University of Bergen, Haukeland Hospital , Norway.
authors.forename: I
authors.initials: I
authors.lastname: Nesthus
authors.affiliation: e Becton Dickinson Immunocytometry Systems , San Jose , CA , USA.
authors.forename: J
authors.initials: J
authors.lastname: Olweus
authors.affiliation: d Division for Hematology, Medical Department B , University of Bergen, Haukeland Hospital , Norway.
authors.forename: Ø
authors.initials: Ø
authors.lastname: Bruserud
keywords: Insulin-like growth factor-1; multiple myeloma; peripheral blood mobilized CD34+ cells