id	author	title	date	pages	extension	mime	words	sentences	flesch	summary	cache	txt
cord-002079-jne14jqf	MacParland, Sonya A.	Lipopolysaccharide and Tumor Necrosis Factor Alpha Inhibit Interferon Signaling in Hepatocytes by Increasing Ubiquitin-Like Protease 18 (USP18) Expression	2016-05-27		.txt	text/plain	7182	388	48	Previous studies from our laboratory have shown that expression of an IFN-stimulated gene (ISG), ubiquitin-like protease (USP)18 is upregulated in chronic HCV infection, leading to impaired hepatocyte responses to IFN-α. We examined the ability of inflammatory stimuli, including tumor necrosis factor alpha (TNF-α), lipopolysaccharide (LPS), interleukin-6 (IL-6) and IL-10 to upregulate hepatocyte USP18 expression and blunt the IFN-α response. Treatment of Huh7.5 cells and primary murine hepatocytes with LPS and TNF-α, but not IL-6 or IL-10, led to upregulated USP18 expression and induced an IFN-α refractory state, which was reversed by USP18 knockdown. These data demonstrate that certain inflammatory stimuli (TNF-␣ and LPS), as well as ischemic injury, but not other cytokines (IL-6 and IL-10) can lead to enhanced hepatocyte USP18 expression and thereby inhibit IFN signaling. Huh7.5 cells and primary murine hepatocytes were treated with IFN-␣ (100 U/ml), TNF-␣ (20 ng/ml), LPS (100 ng/ml), IL-6 (100 ng/ml), or IL-10 (10 ng/ ml) over a 24-h time course, and USP18 expression was determined by quantitative PCR (qPCR) as previously described (8, 9) .	./cache/cord-002079-jne14jqf.txt	./txt/cord-002079-jne14jqf.txt