Type I interferon and pattern recognition receptor signaling following particulate matter inhalation.

ABSTRACT: BACKGROUND: Welding, a process that generates an aerosol containing gases and metal-rich particulates, induces adverse physiological effects including inflammation, immunosuppression and cardiovascular dysfunction. This study utilized microarray technology and subsequent pathway analysis as an exploratory search for markers/mechanisms of in vivo systemic effects following inhalation. Mice were exposed by inhalation to gas metal arc - stainless steel (GMA-SS) welding fume at 40?mg/m3 for 3?hr/d for 10?d and sacrificed 4?hr, 14?d and 28?d post-exposure. Whole blood cells, aorta and lung were harvested for global gene expression analysis with subsequent Ingenuity Pathway Analysis and confirmatory qRT-PCR. Serum was collected for protein profiling. RESULTS: The novel finding was a dominant type I interferon signaling network with the transcription factor Irf7 as a central component maintained through 28?d. Remarkably, these effects showed consistency across all tissues indicating a systemic type I interferon response that was complemented by changes in serum proteins (decreased MMP-9, CRP and increased VCAM1, oncostatin M, IP-10). In addition, pulmonary expression of interferon ? and ? and Irf7 specific pattern recognition receptors (PRR) and signaling molecules (Ddx58, Ifih1, Dhx58, ISGF3) were induced, an effect that showed specificity when compared to other inflammatory exposures. Also, a canonical pathway indicated a coordinated response of multiple PRR and associated signaling molecules (Tlr7, Tlr2, Clec7a, Nlrp3, Myd88) to inhalation of GMA-SS. CONCLUSION: This methodological approach has the potential to identify consistent, prominent and/or novel pathways and provides insight into mechanisms that contribute to pulmonary and systemic effects following toxicant exposure.

SUBMITTER: Erdely A 

PROVIDER: S-EPMC3537608 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature