Recombinant human granulocyte-macrophage colony-stimulating factor induces granule exocytosis from human polymorphonuclear neutrophils.
Exposure of human polymorphonuclear neutrophils (PMNs) to recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) resulted in a time- and concentration-dependent (3-100 units/ml) extracellular release of a specific (vitamin B12-binding protein) but not azurophil granule constituent (myeloperoxidase). Negligible granule exocytosis occurred if PMNs were not preincubated with cytochalasin B prior to contact with GM-CSF. The extent of degranulation elicited with GM-CSF was reduced but not abolished when PMNs were incubated with EGTA in calcium-free medium. GM-CSF did not stimulate a rise in the cytosolic-free calcium concentration ([Ca2+]i), and it had no effect on PMN protein kinase C (PKC) activity.
Smith
R J
RJ
Department of Hypersensitivity Diseases Research, Upjohn Company, Kalamazoo, Michigan 49008.
Justen
J M
JM
Sam
L M
LM
D002118:Calcium / Q000502:physiology; D015550:Cell Degranulation / Q000187:drug effects*; D003115:Colony-Stimulating Factors / Q000494:pharmacology*; D003571:Cytochalasin B / Q000494:pharmacology; D005089:Exocytosis / Q000187:drug effects*; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D006133:Growth Substances / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D009504:Neutrophils / Q000187:drug effects* / Q000201:enzymology / Q000648:ultrastructure; D011493:Protein Kinase C / Q000097:blood / Q000302:isolation & purification; D011994:Recombinant Proteins / Q000494:pharmacology
D003115:Colony-Stimulating Factors; D006133:Growth Substances; D011994:Recombinant Proteins; D003571:Cytochalasin B; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D011493:Protein Kinase C; D002118:Calcium