Interferon-γ enhancement of E-selectin expression on endothelial cells is inhibited by monensin
1997 (English)In: Scandinavian Journal of Immunology, ISSN 0300-9475, E-ISSN 1365-3083, Vol. 46, no 4, 338-343 p.Article in journal (Refereed) Published
The expression of E-selectin reaches a maximum 4–6 h after stimulation of human umbilical vein endothelial cells (HUVEC) in vitro with tumour necrosis factor-α (TNF-α) and then declines to basal level within 24 h. If interferon-γ (IFN-γ) is added to the cell culture medium together with TNF-α the surface expression of E-selectin is augmented and prolonged in a synergistic way. The aim of the present study was to investigate if altered protein glycosylation could explain the IFN-γ induced persistent surface expression of E-selectin. SDS–PAGE analysis of HUVEC glycoproteins, metabolically radiolabelled in the carbohydrate portion, indicated that addition of IFN-γ produced an altered protein glycosylation. Lectin blot analysis using the Sambucus nigra agglutinin lectin also indicated differences in protein glycosylation when HUVEC were incubated with IFN-γ/TNF-α compared to TNF-α alone. The kinetics of surface expression of E-selectin were measured using a cell ELISA assay. When HUVEC were incubated with monensin, a potent inhibitor of late Golgi function, together with both TNF-α and IFN-γ, the additive effect of IFN-γ on E-selectin expression was almost abolished. Since monensin is known to affect glycosylation processing, this experiment suggested that the IFN-γ induced change in protein glycosylation might induce the prolonged surface expression of E-selectin. However, when HUVEC were cultured with IFN-γ/TNF-α in the presence of several different inhibitors of N-glycosylation processing, no significant effect of E-selectin expression was observed. Regulation of adhesion molecule expression after activation of endothelial cells is likely to play a pivotal role for the inflammatory response. Further studies are needed to understand the mechanisms underlying this regulation.
Place, publisher, year, edition, pages
1997. Vol. 46, no 4, 338-343 p.
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-84629DOI: 10.1046/j.1365-3083.1997.d01-135.xOAI: oai:DiVA.org:liu-84629DiVA: diva2:560851