Viral inhibition of IL-1- and neutrophil elastase-induced inflammatory responses in bronchial epithelial cells.
Previously, we elucidated the intracellular mechanisms by which neutrophil elastase (NE) up-regulates inflammatory gene expression in bronchial epithelial cells. In this study, we examine the effects of both IL-1 and NE on inflammatory gene expression in 16HBE14o- bronchial epithelial cells and investigate approaches to abrogate these inflammatory responses. IL-1 induced IL-8 protein production in time- and dose-dependent fashions, an important observation given that IL-8 is a potent neutrophil chemoattractant and a key inflammatory mediator. IL-1 and NE were shown to activate the p38 MAPK pathway in 16HBE14o- cells. Western blot analysis demonstrated IL-1R-associated kinase 1 (IRAK-1) degradation in response to stimulation with both IL-1 and NE. In addition, the expression of dominant negative IRAK-1 (IRAK-1delta), IRAK-2delta, or IRAK-4delta inhibited IL-1- and NE-induced NF-kappaB-linked reporter gene expression. Dominant negative versions of the intracellular adaptor proteins MyD88 (MyD88delta) and MyD88 adaptor-like (Mal P/H) abrogated NE-induced NF-kappaB reporter gene expression. In contrast, only MyD88delta was found to inhibit IL-1-induced NF-kappaB reporter activity. We also investigated the vaccinia virus proteins, A46R and A52R, which have been shown to antagonize IL-1 signaling. Transfection with A46R or A52R cDNA inhibited IL-1- and NE-induced NF-kappaB and IL-8R gene expression and IL-8 protein production in primary and transformed bronchial epithelial cells. Furthermore, cytokine array studies demonstrated that IL-1 and NE can up-regulate the expression of IL-6, oncostatin M, epithelial cell-derived neutrophil activating peptide-78, growth-related oncogene family members, vascular endothelial growth factor, and GM-CSF, with induction of these proteins inhibited by the viral proteins. These findings identify vaccinia virus proteins as possible therapeutic agents for the manifestations of several inflammatory lung diseases.
Carroll
Tomás P
TP
Respiratory Research Division, Royal College of Surgeons in Ireland, Education and Research Center, Beaumont Hospital, Dublin, Ireland.
Greene
Catherine M
CM
Taggart
Clifford C
CC
Bowie
Andrew G
AG
O'Neill
Shane J
SJ
McElvaney
Noel G
NG
D048868:Adaptor Proteins, Signal Transducing / Q000276:immunology / Q000378:metabolism; D000943:Antigens, Differentiation / Q000276:immunology / Q000378:metabolism; D015153:Blotting, Western; D001980:Bronchi / Q000276:immunology* / Q000821:virology*; D002460:Cell Line; D004847:Epithelial Cells / Q000276:immunology* / Q000821:virology*; D015870:Gene Expression / Q000276:immunology; D005786:Gene Expression Regulation / Q000276:immunology; D006801:Humans; D007249:Inflammation / Q000276:immunology / Q000821:virology; D007375:Interleukin-1 / Q000096:biosynthesis / Q000276:immunology*; D053592:Interleukin-1 Receptor-Associated Kinases; D016209:Interleukin-8 / Q000276:immunology / Q000378:metabolism; D019272:Leukocyte Elastase / Q000276:immunology* / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000276:immunology / Q000378:metabolism; D053594:Myeloid Differentiation Factor 88; D011494:Protein Kinases / Q000276:immunology / Q000378:metabolism; D011971:Receptors, Immunologic / Q000276:immunology / Q000378:metabolism; D017472:Receptors, Interleukin-1 / Q000276:immunology / Q000378:metabolism; D051197:Toll-Like Receptor 4 / Q000096:biosynthesis / Q000276:immunology; D014162:Transfection; D014764:Viral Proteins / Q000276:immunology; D048051:p38 Mitogen-Activated Protein Kinases / Q000276:immunology / Q000378:metabolism
C413651:A46R protein, vaccinia virus; C413650:A52R protein, vaccinia virus; D048868:Adaptor Proteins, Signal Transducing; D000943:Antigens, Differentiation; D007375:Interleukin-1; D016209:Interleukin-8; C507779:MYD88 protein, human; D008562:Membrane Glycoproteins; D053594:Myeloid Differentiation Factor 88; D011971:Receptors, Immunologic; D017472:Receptors, Interleukin-1; C434984:TIRAP protein, human; C495345:TLR4 protein, human; D051197:Toll-Like Receptor 4; D014764:Viral Proteins; D011494:Protein Kinases; D053592:Interleukin-1 Receptor-Associated Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D019272:Leukocyte Elastase