The lipopolysaccharide-triggered mesangial transcriptome: Evaluating the role of interferon regulatory factor-1.
BACKGROUND: Presently, we do not have a clear picture of how the mesangial transcriptome evolves following stimulation. The present study was designed to address this, using an innate trigger to stimulate murine mesangial cells. METHODS: Three independent mesangial cell lines derived from C57BL/6 mice were stimulated with lipopolysaccharide (LPS). The mesangial cell transcriptomes were defined 1, 6, 24, and 60 hours poststimulation with LPS, using a 17,000 gene oligonucleotide array. RESULTS: Interferon regulatory factor-1 (IRF-1), ScyA2/MCP1, ScyA20/MIP3alpha (ScyB1/Gro1, and ScyB2/MIP2alpha/Gro2 were the earliest genes to be hyperexpressed after LPS stimulation. Later-appearing genes included ScyA7/MCP3, ScyD1/fractalkine, GM-CSF/CSF-2, PDGF, epiregulin, NfKb, C/EBP, TIMP-1, MMP11, MMP13, PTGS2/ COX2, SpI2-1, Spp1, PAI-1, VCAM-1, C3, and defensin-beta1, among others. Several of these changes were validated by real-time polymerase chain reaction (PCR) or enzyme-linked immunosorbent assay (ELISA). Rapid IRF-1 hyperexpression was also noted following stimulation of mesangial cells with peptidoglycan, poly I:poly C, interferon-gamma?(IFN-gamma), and heat-aggregated IgG. However, the blocking of IRF-1 using RNA interference and the use of mesangial cells isolated from IRF-1-deficient mice could not substantiate an obligatory role for IRF-1 in LPS-induced mesangial cell activation. Likewise, IRF-1 deficiency did not impact the development of anti-glomerular basement membrane (GBM)-induced immune nephritis. CONCLUSION: Innate stimuli such as LPS appear to trigger successive waves of mesangial cell gene expression. Although IRF-1 surfaces as an "early-on, early-off" transcription factor following several different triggers, it does not appear to be an essential molecule for mesangial cell activation by innate triggers or for anti-GBM disease.[1]References
- The lipopolysaccharide-triggered mesangial transcriptome: Evaluating the role of interferon regulatory factor-1. Fu, Y., Xie, C., Yan, M., Li, Q., Joh, J.W., Lu, C., Mohan, C. Kidney Int. (2005) [Pubmed]
Annotations and hyperlinks in this abstract are from individual authors of WikiGenes or automatically generated by the WikiGenes Data Mining Engine. The abstract is from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.About WikiGenesOpen Access LicencePrivacy PolicyTerms of Useapsburg