| Autor: |
Rossato M; Department of Pathology, Division of General Pathology, University of Verona, Verona, Italy., Cencig S, Gasperini S, Cassatella MA, Bazzoni F |
| Jazyk: |
angličtina |
| Zdroj: |
European journal of immunology [Eur J Immunol] 2007 Nov; Vol. 37 (11), pp. 3176-89. |
| DOI: |
10.1002/eji.200737625 |
| Abstrakt: |
We have recently reported that the ability of IL-10 to rapidly exert its anti-inflammatory effects on human neutrophils is dependent upon exposure of these cells to LPS for at least 3-4 h. Here, we demonstrate that, in neutrophils "preconditioned" by LPS, IL-10 primarily targets the transcription of TNF-alpha, CXCL8 and IL-1ra genes, as revealed by primary transcript real-time RT-PCR. We also show that IL-10-induced transcriptional repression of TNF-alpha and CXCL8 genes consists of two distinct phases: an early one, occurring rapidly and in a protein synthesis-independent manner, followed by a second phase, more delayed and dependent on protein synthesis. Interestingly, the protein synthesis dependence of the latter phase coincides with a reduced ability of IL-10 to induce STAT3 tyrosine phosphorylation. Importantly, inhibition of IL-10-induced STAT3 activation and IL-10-suppressive action by a prolonged exposure to cycloheximide (CHX) was observed to occur also in human monocytes and was caused by a defective IL-10-mediated activation of Jak1 and Tyk2 kinases. Taken together, our findings suggest that CHX interferes with the IL-10-mediated intracellular signaling pathway by interrupting events upstream of STAT3 activation. These data question the concept of the requirement of an IL-10-induced mediator as the unique mechanism to execute IL-10 anti-inflammatory program. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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