Membrane interleukin 1 induction on human endothelial cells and dermal fibroblasts
Kurt-Jones, E.A.; Fiers, W.; Pober, J.S.
Journal of Immunology 139(7): 2317-2324
1987
ISSN/ISBN: 0022-1767 PMID: 3116078 Document Number: 299095
Human endothelial cells and dermal fibroblasts both expressed a membrane-associated interleukin 1 (IL-1) activity when stimulated with either recombinant tumour 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.alpha. and IL-1.beta. mRNA in response to TNF, lymphotoxin, and recombinant IL-I 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-I.