Interleukin-1 synergizes with granulocyte-macrophage colony-stimulating factor on granulocytic colony formation by intermediate production of granulocyte colony-stimulating factor.
Interleukin-1 (IL-1) was found to act synergistically with granulocyte-macrophage colony-stimulating factor (GM-CSF) on granulocytic colony growth of normal human bone marrow cells, depleted of mononuclear phagocytes and T lymphocytes. Using CD34/HLA-DR-enriched bone marrow cells we demonstrated that this activity of IL-1 was not a direct action on hematopoietic progenitor cells, but an effect of an intermediate factor produced by residual accessory cells in response to IL-1. Neutralization experiments using an anti-IL-6 antiserum showed that IL-1-induced IL-6 did not contribute to the observed synergy. Furthermore, IL-6 by itself had neither a direct stimulatory effect on CFU-GM colony growth, nor did it act synergistically with GM-CSF on granulocytic or monocytic colony formation. Neutralization experiments with an anti-G-CSF monoclonal antibody showed that IL-1-induced G-CSF production was responsible for the synergy with GM-CSF. Using combinations of G-CSF and GM-CSF this synergistic activity could be detected at concentrations of G-CSF as low as 0.1 ng/mL (10 U/mL). Our results indicate that IL-1, but not IL-6, stimulates the GM-CSF-dependent proliferation of relatively mature myeloid progenitor cells in the presence of small numbers of accessory cells.
Schaafsma
M R
MR
Department of Hematology, University Medical Center, Leiden, The Netherlands.
Falkenburg
J H
JH
Duinkerken
N
N
Van Damme
J
J
Altrock
B W
BW
Willemze
R
R
Fibbe
W E
WE
D018952:Antigens, CD34; D000943:Antigens, Differentiation; D001854:Bone Marrow Cells; D002469:Cell Separation; D003114:Colony-Forming Units Assay; D003115:Colony-Stimulating Factors / Q000096:biosynthesis*; D004357:Drug Synergism; D016179:Granulocyte Colony-Stimulating Factor; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D006098:Granulocytes / Q000166:cytology*; D006133:Growth Substances; D006684:HLA-DR Antigens / Q000032:analysis; D006410:Hematopoiesis / Q000187:drug effects; D006801:Humans; D066298:In Vitro Techniques; D007375:Interleukin-1 / Q000008:administration & dosage*; D015850:Interleukin-6 / Q000494:pharmacology
D018952:Antigens, CD34; D000943:Antigens, Differentiation; D003115:Colony-Stimulating Factors; D006133:Growth Substances; D006684:HLA-DR Antigens; D007375:Interleukin-1; D015850:Interleukin-6; D016179:Granulocyte Colony-Stimulating Factor; D016178:Granulocyte-Macrophage Colony-Stimulating Factor