Akira Kado1, Takeya Tsutsumi2, Kenichiro Enooku1, Hidetaka Fujinaga1, Kazuhiko Ikeuchi3, Kazuya Okushin1,4, Kyoji Moriya3,4, Hiroshi Yotsuyanagi2, Kazuhiko Koike5. 1. Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan. 2. Division of Infectious Diseases, Advanced Clinical Research Center, Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo, 108-8639, Japan. 3. Department of Infectious Diseases, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan. 4. Department of Infection Control and Prevention, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan. 5. Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan. kkoike-tky@umin.ac.jp.
Abstract
BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) consists of nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH); the latter progresses to liver cirrhosis and hepatocellular carcinoma. Discriminating NASH from NAFL typically involves liver biopsy. The mechanism of NASH progression is unclear but may involve immunological pathways. In this study, we examined expression levels of cytokine- and chemokine-encoding genes in peripheral blood mononuclear cells (PBMCs) from NAFLD patients and established immunological criteria for discriminating NASH from NAFL. METHODS: PBMCs were obtained from 54 patients diagnosed histologically with NAFLD (NAFL, 18; NASH, 36). mRNA was extracted from PBMCs, and expression levels of cytokine- and chemokine-encoding genes were determined by quantitative real-time PCR. Statistical analysis was performed by nonparametric test. RESULTS: Expression levels of interferon (IFN)γ, interleukin (IL)2, IL15, C-C-motif chemokine ligand (CCL)2, IL10, and C-X-C-motif chemokine ligand (CXCL)11 were significantly upregulated in NASH patients compared with NAFL patients. Moreover, their expression levels were positively correlated with the degree of ballooning of hepatocytes but not of steatosis or lobular inflammation. We focused on those encoding IL10, IFNγ, and CCL2, and developed a scoring system to discriminate NASH from NAFL. The discriminatory power of the criteria was validated in an independent cohort. CONCLUSIONS: Expression levels of the cytokine- and chemokine-encoding genes in PBMCs were positively correlated with ballooning, suggesting their utility for the diagnosis of NASH. The data indicate that peripheral as well as intrahepatic immunity is involved in the progression of NASH. Our findings afford new insight into immunological mechanisms of NASH and will facilitate its noninvasive diagnosis.
BACKGROUND:Nonalcoholic fatty liver disease (NAFLD) consists of nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH); the latter progresses to liver cirrhosis and hepatocellular carcinoma. Discriminating NASH from NAFL typically involves liver biopsy. The mechanism of NASH progression is unclear but may involve immunological pathways. In this study, we examined expression levels of cytokine- and chemokine-encoding genes in peripheral blood mononuclear cells (PBMCs) from NAFLDpatients and established immunological criteria for discriminating NASH from NAFL. METHODS: PBMCs were obtained from 54 patients diagnosed histologically with NAFLD (NAFL, 18; NASH, 36). mRNA was extracted from PBMCs, and expression levels of cytokine- and chemokine-encoding genes were determined by quantitative real-time PCR. Statistical analysis was performed by nonparametric test. RESULTS: Expression levels of interferon (IFN)γ, interleukin (IL)2, IL15, C-C-motif chemokine ligand (CCL)2, IL10, and C-X-C-motif chemokine ligand (CXCL)11 were significantly upregulated in NASH patients compared with NAFL patients. Moreover, their expression levels were positively correlated with the degree of ballooning of hepatocytes but not of steatosis or lobular inflammation. We focused on those encoding IL10, IFNγ, and CCL2, and developed a scoring system to discriminate NASH from NAFL. The discriminatory power of the criteria was validated in an independent cohort. CONCLUSIONS: Expression levels of the cytokine- and chemokine-encoding genes in PBMCs were positively correlated with ballooning, suggesting their utility for the diagnosis of NASH. The data indicate that peripheral as well as intrahepatic immunity is involved in the progression of NASH. Our findings afford new insight into immunological mechanisms of NASH and will facilitate its noninvasive diagnosis.
Authors: John Willy Haukeland; Jan Kristian Damås; Zbigniew Konopski; Else Marit Løberg; Terese Haaland; Ingeborg Goverud; Peter A Torjesen; Kåre Birkeland; Kristian Bjøro; Pål Aukrust Journal: J Hepatol Date: 2006-03-20 Impact factor: 25.083
Authors: Joyce J Ruitenberg; Candice B Mulder; Vernon C Maino; Alan L Landay; Smita A Ghanekar Journal: BMC Immunol Date: 2006-05-25 Impact factor: 3.615
Authors: R de Waal Malefyt; J Haanen; H Spits; M G Roncarolo; A te Velde; C Figdor; K Johnson; R Kastelein; H Yssel; J E de Vries Journal: J Exp Med Date: 1991-10-01 Impact factor: 14.307