Granulocyte-macrophage colony-stimulating factor requires interaction with accessory cells or granulocyte-colony stimulating factor for full stimulation of human myeloid progenitors.
Human recombinant GM-CSF (rGM-CSF) was tested on highly purified and fractionated CFU-GM subsets. The fractionation was performed with the DS1-1 monoclonal antibody (MoAb), which distinguishes early and late CFU-GM. On whole bone marrow cells, rGM-CSF had a colony-stimulating activity comparable to that of known sources of CSFs, ie, the supernatant (SN) of TPA 30-1 or 5637 cell lines, used as control. A greatly reduced activity was observed when CFU-GM were depleted of phagocytizing and E rosetting cells (colony growth of 27% as compared with control). On fractionated CFU-GM, the rGM-CSF activity was even more reduced on both early and late progenitors (18% and 6% of colony growth, respectively). However, when rGM-CSF was used together with rG-CSF at suboptimal concentrations, the colony growth reached values analogous to that of control cultures. A synergistic interaction between rGM-CSF and rG-CSF in stimulating either early or late myeloid progenitors was observed. The results suggest that the activity of rGM-CSF on CFU-GM is mainly exerted through cooperation with accessory cells. r-G-CSF is one of the factors that can synergistically cooperate with r-GM-CSF in the myelopoietic stimulation.
Ferrero
D
D
Dipartimento di Medicina, Università di Torino, Italy.
Tarella
C
C
Badoni
R
R
Caracciolo
D
D
Bellone
G
G
Pileri
A
A
Gallo
E
E
D001853:Bone Marrow / Q000502:physiology*; D002450:Cell Communication; D002469:Cell Separation; D003114:Colony-Forming Units Assay; D003115:Colony-Stimulating Factors / Q000494:pharmacology*; D004357:Drug Synergism; D016179:Granulocyte Colony-Stimulating Factor; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D006133:Growth Substances / Q000494:pharmacology*; D006412:Hematopoietic Stem Cells / Q000502:physiology*; D006801:Humans; D011994:Recombinant Proteins / Q000494:pharmacology
D003115:Colony-Stimulating Factors; D006133:Growth Substances; D011994:Recombinant Proteins; D016179:Granulocyte Colony-Stimulating Factor; D016178:Granulocyte-Macrophage Colony-Stimulating Factor