Interferon-beta is a potent inducer of interferon regulatory factor-1/2-dependent IP-10/CXCL10 expression in primary human endothelial cells.
Most virus-infected cells release interferon-beta (IFN-beta) as a powerful inducer of antiviral defense. Endothelial cells tightly regulate local immune cell recruitment by expression of adhesion molecules and chemokines. Here, we studied the transcriptional regulation of IFN-beta-induced chemokine expression in primary human endothelial cells. IFN-beta moderately increased monocyte chemoattractant protein-1/CCL2 and potently raised IFN-gamma-inducible protein-10/CXCL10 mRNA steady-state levels and protein release, while no effect was detected on various other chemokines. As shown by transient transfections, induction of CXCL10 expression depends on an IFN-stimulated response element (ISRE) within the CXCL10 promoter. A double point mutation of the putative IFN regulatory factor (IRF)-1/2 binding site within this ISRE motif abolished IFN-beta-induced promoter activity. In electrophoretic mobility shift assays, this ISRE motif showed a basal IRF-2 and an IFN-beta-inducible IRF-1 and augmented IRF-2 binding. Furthermore, stimulation with IFN-beta induced a rapid nuclear translocation of signal transducer and activator of transcription 1 (STAT1) and STAT2 and their transient binding to a gamma-activated site within the CCL2 promoter. The kinetics of transient STAT1 binding to this gamma-activated site element correlated with the amount of Y701-phosphorylated nuclear STAT1, while S727-phosphorylated nuclear STAT1 remained stable over 24 h after stimulation. Therefore, IFN-beta potently induces endothelial chemokine expression at the transcriptional level.
Buttmann
Mathias
M
Department of Neurology, Julius-Maximilians University, Josef-Schneider-Strasse 11, DE-97080 Würzburg, Germany. m.buttmann@uni-wuerzburg.de
Berberich-Siebelt
Friederike
F
Serfling
Edgar
E
Rieckmann
Peter
P
D021581:Active Transport, Cell Nucleus; D002467:Cell Nucleus / Q000378:metabolism; D002478:Cells, Cultured; D018932:Chemokine CCL2 / Q000378:metabolism; D054357:Chemokine CXCL10; D019743:Chemokines, CXC / Q000235:genetics / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D024202:Electrophoretic Mobility Shift Assay; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism*; D006801:Humans; D050856:Interferon Regulatory Factor-1 / Q000378:metabolism*; D050836:Interferon Regulatory Factor-2 / Q000378:metabolism*; D000068556:Interferon beta-1a; D016899:Interferon-beta / Q000378:metabolism* / Q000494:pharmacology; D010766:Phosphorylation; D011401:Promoter Regions, Genetic / Q000187:drug effects; D012333:RNA, Messenger / Q000378:metabolism; D050794:STAT1 Transcription Factor / Q000378:metabolism; D050795:STAT2 Transcription Factor / Q000378:metabolism; D013997:Time Factors; D014158:Transcription, Genetic / Q000187:drug effects; D014162:Transfection; D015854:Up-Regulation / Q000187:drug effects
C111835:CCL2 protein, human; C114753:CXCL10 protein, human; D018932:Chemokine CCL2; D054357:Chemokine CXCL10; D019743:Chemokines, CXC; C494257:IRF1 protein, human; C494229:IRF2 protein, human; D050856:Interferon Regulatory Factor-1; D050836:Interferon Regulatory Factor-2; D012333:RNA, Messenger; D050794:STAT1 Transcription Factor; C494079:STAT1 protein, human; D050795:STAT2 Transcription Factor; C494084:STAT2 protein, human; D016899:Interferon-beta; D000068556:Interferon beta-1a