title: Stem cell responses in myelosuppressed mice following sequential treatment with recombinant human interleukin 1 (rHuIL-1), recombinant murine interleukin 3 (rMuIL-3) and recombinant human macrophage colony-stimulating factor (rHuM-CSF).
abstract: In vivo, recombinant human interleukin 1 alpha (rHuIL-1 alpha) + recombinant human macrophage colony-stimulating factor (rHuM-CSF) (IL-1 + M-CSF) effectively serves as a rescue agent for myelosuppression by enhancing the recovery of hematopoietic stem cell (HSC) subpopulations following treatment with 5-fluorouracil (5-FU). Because in vitro studies have suggested that hematopoietic recovery in 5-FU-treated bone marrow (FUBM) may proceed from a 5-FU resistant, (IL-1 + IL-3 + M-CSF-responsive) high proliferative potential HSC subpopulation of colony forming cells (HPP-CFC), studies were carried out to determine whether the addition of recombinant murine interleukin 3 (rMuIL-3) (IL-3) to either IL-1 or IL-1 + M-CSF would further enhance the recovery of HSC subpopulations in myelosuppressed C57Bl/6 mice. With the exception of the HPP-CFC, IL-3 dampened, rather than enhanced, the accelerated recovery of 8 d and 12 d colony forming units-spleen (8 d and 12 d CFU-S) and the committed macrophage progenitor (CFU-M) associated with in vivo treatment with IL-1 alone. Similarly, IL-3 interfered with the enhanced recovery of those HSC subpopulations in FUBM influenced by the synergistic interaction of IL-1 + M-CSF. This interference, however, was observed only when the rMuIL-3 was administered on day 2 or 3 of a four-day treatment with IL-1 + M-CSF. There was, however, no evidence that IL-3 exerted a negative influence on the restoration of granulocytes in the myelosuppressed animals. Moreover, sequencing studies provided data suggesting that the dampening effects of IL-3 on the synergistic interaction of IL-1 + M-CSF resulted from both an enhanced differentiation of the more primitive HSC subpopulations and a significant, but preferential, mobilization of the more mature 8 d CFU-S and CFU-M to extramedullary organs and that the mobilization of these more mature HSC subpopulations was temporally linked to their generation from the recovering HPP-CFC and 12 d CFU-S subpopulations.
authors.affiliation: Department of Radiation Oncology, Leo Jenkins Cancer Center, East Carolina University School of Medicine, Greenville, North Carolina 27858.
authors.forename: C J
authors.initials: CJ
authors.lastname: Kovacs
authors.forename: J P
authors.initials: JP
authors.lastname: Harrell
authors.forename: M J
authors.initials: MJ
authors.lastname: Evans
authors.forename: R S
authors.initials: RS
authors.lastname: Abernathy
authors.forename: C J
authors.initials: CJ
authors.lastname: Roberts
authors.forename: R M
authors.initials: RM
authors.lastname: Johnke
mesh_terms: D000818:Animals; D005260:Female; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000187:drug effects*; D006801:Humans; D016867:Immunocompromised Host; D007375:Interleukin-1 / Q000494:pharmacology*; D007377:Interleukin-3 / Q000494:pharmacology*; D016173:Macrophage Colony-Stimulating Factor / Q000494:pharmacology*; D051379:Mice; D008810:Mice, Inbred C57BL; D011994:Recombinant Proteins / Q000494:pharmacology
chemical_list: D007375:Interleukin-1; D007377:Interleukin-3; D011994:Recombinant Proteins; D016173:Macrophage Colony-Stimulating Factor