Autor: |
Oliveira IC; Department of Microbiology, New York University Medical Center, New York 10016., Sciavolino PJ, Lee TH, Vilcek J |
Jazyk: |
angličtina |
Zdroj: |
Proceedings of the National Academy of Sciences of the United States of America [Proc Natl Acad Sci U S A] 1992 Oct 01; Vol. 89 (19), pp. 9049-53. |
DOI: |
10.1073/pnas.89.19.9049 |
Abstrakt: |
The chemotactic cytokine interleukin 8 (IL-8) is produced upon stimulation by various agents in many cell types, including connective-tissue fibroblasts. Tumor necrosis factor (TNF) and IL-1 are potent inducers of IL-8 expression. Earlier we showed that TNF-induced stimulation of IL-8 mRNA accumulation in human FS-4 fibroblasts was inhibited by interferon beta (IFN-beta) or IFN-gamma. Here we show that this inhibition is not specific for TNF, since IFN-beta also reduced IL-8 mRNA accumulation induced by IL-1 or the double-stranded RNA poly (I-C). Treatment with IFN-beta also decreased TNF-induced IL-8 protein accumulation. Interestingly, the inhibitory effect was much less pronounced when IFN-beta was added greater than or equal to 1 hr before TNF. The inhibitory action of IFN-beta on IL-8 mRNA accumulation was undiminished in the presence of inhibitors of protein synthesis. Nuclear run-on assays demonstrated that IFN-beta caused a marked inhibition of TNF-induced IL-8 gene transcription; the transcriptional activation of several other TNF-induced genes was not inhibited by IFN-beta. The results suggest that the specific inhibition of the transcriptional activation of IL-8 by IFN is due either to a transient inactivation of a factor required for IL-8 transcription or to the activation of a selective inhibitory factor. |
Databáze: |
MEDLINE |
Externí odkaz: |
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