title: Expression of IL-1 and tumor necrosis factor by endothelial cells: role in stimulating fibroblast PGE2 synthesis.
abstract: We describe the elaboration by endothelial cells of activity that stimulates fibroblast PGE2 production. Culture supernates of human umbilical vein endothelial cells (ECSN) at concentrations of 2.5 to 25% stimulated human foreskin fibroblast PGE2 production 6 to 180-fold. Following molecular sieve chromatography, peak activity eluted with an Mr of 14-18,000. In a standard IL-1 assay, neither ECSN or 14-18,000 Mr fractions possessing PGE2 stimulatory activity were able to stimulate murine thymocyte proliferation in response to PHA. Immunoperoxidase staining of endothelial cells demonstrated intracellular IL-1; after addition of exogenous IL-1 endothelial cells also stained for tumor necrosis factor (TNF). IL-1 and TNF are known to be synergistic in stimulating fibroblast PGE2 synthesis. Thus, elaboration of TNF by endothelial cells may allow detection of IL-1 in fibroblast PGE2 assays when the concentration of IL-1 is inadequate to stimulate thymocyte proliferation. Interactions of cytokines elaborated by cells may play an important role in effects on target cells.
authors.affiliation: Division of Rheumatic Diseases, Veterans Administration Medical Center, Newington, CT 06111.
authors.forename: W R
authors.initials: WR
authors.lastname: Shanahan
authors.forename: W W
authors.initials: WW
authors.lastname: Hancock
authors.forename: J H
authors.initials: JH
authors.lastname: Korn
mesh_terms: D000818:Animals; D002455:Cell Division / Q000187:drug effects; D002850:Chromatography, Gel; D015232:Dinoprostone / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism*; D005347:Fibroblasts / Q000378:metabolism*; D005786:Gene Expression Regulation; D006801:Humans; D007124:Immunoenzyme Techniques; D007375:Interleukin-1 / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D013950:Thymus Gland / Q000166:cytology; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D014471:Umbilical Veins / Q000166:cytology
chemical_list: D007375:Interleukin-1; D014409:Tumor Necrosis Factor-alpha; D015232:Dinoprostone