title: Production of granulocyte-macrophage colony-stimulating factor by cultured human tracheal epithelial cells.
abstract: We have evaluated the capacity of cultured human respiratory epithelial cells (HTE) to produce granulocyte-macrophage colony-stimulating factor (GM-CSF) and have examined the ability of proinflammatory stimuli and of glucocorticoids to modulate the production of GM-CSF by these cells. Conditioned medium (CM) was obtained after 24-hr culture of HTE in the presence or absence of serum (5%) and was assayed for GM-CSF activity using the M-07e cell line, which proliferates in response to GM-CSF and interleukin-3 (IL-3). HTE produced 1.1 +/- 0.7 and 2.1 +/- 1.5 ng GM-CSF/10(6) cells in the presence or absence of serum, respectively (n = 4). The identity of this activity as GM-CSF was established by neutralization with specific antibody to GM-CSF, while antibody to IL-3 was without effect. Dexamethasone (10(-6) M) inhibited basal GM-CSF release to below the limit of detection of the assay (0.12 ng GM-CSF/ml conditioned media). GM-CSF release was significantly enhanced by 10(-6) M histamine (1.6 +/- 0.7 versus 2.13 +/- 0.8 ng GM-CSF/10(6) cells; n = 9) and 5 ng/ml interleukin-1 (IL-1) (0.6 +/- 0.2 versus 3.2 +/- 0.5 ng GM-CSF/10(6) cells; n = 3). Stimulation of GM-CSF release by IL-1 was dose-dependent. A significant increase in GM-CSF activity was observed with 0.1 ng/ml, while maximal stimulation occurred at 5 ng/ml IL-1. In kinetic studies, GM-CSF activity was first detected in CM from cells incubated in the absence of stimulus at 8 hr of incubation, and continued to increase up to 24 hr. IL-1 stimulated GM-CSF activity was detected in CM as early as 4 hr and continued to increase significantly up to 24 hr. Thus, human tracheal epithelial cells release GM-CSF and this release is regulated by inflammatory mediators and glucocorticoids.
authors.affiliation: Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: L
authors.initials: L
authors.lastname: Churchill
authors.forename: B
authors.initials: B
authors.lastname: Friedman
authors.forename: R P
authors.initials: RP
authors.lastname: Schleimer
authors.forename: D
authors.initials: D
authors.lastname: Proud
mesh_terms: D000328:Adult; D000368:Aged; D002478:Cells, Cultured; D003907:Dexamethasone / Q000494:pharmacology; D004306:Dose-Response Relationship, Immunologic; D004848:Epithelium / Q000276:immunology; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000096:biosynthesis* / Q000187:drug effects; D006632:Histamine / Q000494:pharmacology; D006801:Humans; D007375:Interleukin-1 / Q000276:immunology; D007377:Interleukin-3 / Q000096:biosynthesis; D007700:Kinetics; D008875:Middle Aged; D014132:Trachea / Q000276:immunology*
chemical_list: D007375:Interleukin-1; D007377:Interleukin-3; D003907:Dexamethasone; D006632:Histamine; D016178:Granulocyte-Macrophage Colony-Stimulating Factor