title: Membrane interleukin 1 induction on human endothelial cells and dermal fibroblasts.
abstract: Human endothelial cells and dermal fibroblasts both expressed a membrane-associated interleukin 1 (IL-1) activity when stimulated with either recombinant tumor necrosis factor (TNF) or recombinant lymphotoxin but stimulated endothelial cells expressed significantly more membrane IL-1 per cell than did fibroblasts. Lipopolysaccharide induced membrane IL-1 activity on endothelial cells but not fibroblasts. Interferon-gamma treatment of endothelial cells and fibroblasts had no direct effect on membrane IL-1 expression and little effect when used as a pretreatment for TNF or lipopolysaccharide stimulation. Endothelial cell membrane IL-1 activity was induced within 24 hr of culture with TNF or lipopolysaccharide, and increased up to 72 hr of incubation. Antibodies raised against human monocyte-derived IL-1 species neutralized the membrane IL-1 activity of TNF-stimulated endothelial cells. Both absorption studies and neutralization with specific sera indicated that endothelial cell membrane IL-1 is structurally related to IL-1 alpha. Endothelial cells expressed both IL-1 beta mRNA in response to TNF, lymphotoxin, and recombinant IL-1 species, as detected by Northern blot analysis. These studies demonstrate that endothelial cells can be activated to express a cell-surface IL-1 activity which is structurally, as well as functionally, related to the secreted form of IL-1.
mesh_terms: D002462:Cell Membrane / Q000032:analysis; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology; D007375:Interleukin-1 / Q000096:biosynthesis*; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008233:Lymphotoxin-alpha / Q000494:pharmacology*; D008565:Membrane Proteins / Q000096:biosynthesis*; D011994:Recombinant Proteins / Q000494:pharmacology; D012867:Skin / Q000166:cytology; D013268:Stimulation, Chemical; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
chemical_list: D007375:Interleukin-1; D008070:Lipopolysaccharides; D008233:Lymphotoxin-alpha; D008565:Membrane Proteins; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma