References1. Leung PS, Rossaro L, Davis PA, Park O, Tanaka A, Kikuchi K, et al.

Antimitochondrial antibodies in acute liver failure: implications for pri-mary biliary cirrhosis. HEPATOLOGY 2007;46:1436-1442.

2. Ferret PJ, Hammoud R, Tulliez M, Tran A, Trebeden H, Jaffray P, et al.Detoxification of reactive oxygen species by a nonpeptidyl mimic of super-oxide dismutase cures acetaminophen-induced acute liver failure in themouse. HEPATOLOGY 2001;33:1173-1180.

3. Wu CT, Eiserich JP, Ansari AA, Coppel RL, Balasubramanian S, BowlusCL, et al. Myeloperoxidase-positive inflammatory cells participate in bileduct damage in primary biliary cirrhosis through nitric oxide-mediatedreactions. HEPATOLOGY 2003;38:1018-1025.

4. Bernal W, Ma Y, Smith HM, Portmann B, Wendon J, Vergani D. Thesignificance of autoantibodies and immunoglobulins in acute liver failure:a cohort study. J Hepatol 2007;47:664-670.

5. Ma Y, Okamoto M, Thomas MG, Bogdanos DP, Lopes AR, Portmann B, etal. Antibodies to conformational epitopes of soluble liver antigen define asevere form of autoimmune liver disease. HEPATOLOGY 2002;35:658-664.

6. Longhi MS, Ma Y, Bogdanos DP, Cheeseman P, Mieli-Vergani G, Ver-gani D. Impairment of CD4(�)CD25(�) regulatory T-cells in autoim-mune liver disease. J Hepatol 2004;41:31-37.

7. Longhi MS, Ma Y, Mitry RR, Bogdanos DP, Heneghan M, Cheeseman P, etal. Effect of CD4� CD25� regulatory T-cells on CD8 T-cell function inpatients with autoimmune hepatitis. J Autoimmun 2005;25:63-71.

8. Longhi MS, Hussain MJ, Mitry RR, Arora SK, Mieli-Vergani G, VerganiD, et al. Functional study of CD4�CD25� regulatory T cells in healthand autoimmune hepatitis. J Immunol 2006;176:4484-4491.

Copyright © 2008 by the American Association for the Study of Liver Diseases.Published online in Wiley InterScience (www.interscience.wiley.com).DOI 10.1002/hep.22179Potential conflict of interest: Nothing to report.

Reply:

Unless we are both studying the same sera, there is no basis ofcomparison. In our clinical cases and I assume their clinical series,many types of ALF were studied and we both found AMAs when weused the same method. It is also obvious that no international stan-dardization exists, and measurements of all these antibodies will not bestandardized until the release of the newer multiphasic kits in 2009 andbeyond.

M. ERIC GERSHWIN, M.D.Division of Rheumatology/AllergyUniversity of California, Davis Medical CenterSacramento, CA

Copyright © 2008 by the American Association for the Study of Liver Diseases.Published online in Wiley InterScience (www.interscience.wiley.com).DOI 10.1002/hep.22305Potential conflict of interest: Nothing to report.

Adoptive Transfer of Regulatory T Cells in an Animal Model of a Diet-Induced Fatty Liver

To the Editor:

I read with interest an excellent study by Ma et al. that clarifiedthe mechanisms of progression from hepatic steatosis to nonalco-holic steatohepatitis (NASH) in a mouse model of a high-diet-induced fatty liver.1 The authors revealed that CD4� CD25�

forkhead box P3� hepatic regulatory T cells (T regs) decreasedduring the administration of a high-fat diet, and the levels of T regswere less than half of those in control mice at the end of the 8-weekexperiment. Marked reduction of T regs, which was caused byapoptosis due to oxidative stress, was associated with enhancedexpression of tumor necrosis factor (TNF) alpha and its intracellu-lar mediators in liver. Adoptive-transferred T regs suppressed high-fat diet-induced intrahepatic TNF alpha signaling. Mice in whichT regs were depleted or T regs were transferred, both of which werefed diets containing a high amount of fat, were given a singlerelatively low dose of lipopolysaccharide (LPS) (100 �g/mouse) toinduce hepatic injury. Six hours after injection of LPS, LPS-in-duced liver damage was compared between the groups. A pretreat-ment with adoptive transfer of T regs significantly attenuatedhepatotoxicity of LPS in mice with hepatic steatosis. The authorsspeculate that enhanced LPS signaling followed by proinflamma-tory cytokine production as a second hit necessary for the progres-sion from steatosis to nonalcoholic steatohepatitis can be reducedby restoring the function of T regs.

T regs are engaged in the regulation of organ-specific immuneresponses to pathogens and self-proteins. A recent in vitro studyindicates that activated T regs rapidly inhibit induction of Th1cytokine mRNA, whereas suppression of anti-inflammatory Th2cytokines is delayed.2 This article by Ma and colleagues may be thecornerstone for a better understanding of a variety of immune-related liver diseases in addition to nonalcoholic liver disease. Iwould like to ask the authors whether animal models with chronic

endotoxemia, which are described in a recent article,3 are moresuitable than those with acute endotoxemia for the study to inves-tigate the role of T regs in liver disease. Mild chronic endotoxemiahas been observed in chronic liver disease,4 chronic kidney disease,5

and chronic cardiovascular disease.6

TETSUJI FUJITA, M.D.Department of SurgeryJikei University School of MedicineTokyo, Japan

References1. Ma X, Hua J, Mohamood AR, Hamad ARA, Ravi R, Li Z. A high-fat diet

and regulatory T cells influence susceptibility to endotoxin-induced liverinjury. HEPATOLOGY 2007;46:1519-1529.

2. Oberle N, Eberhardt N, Falk CS, Krammer PH, Suri-Payer E. Rapidsuppression of cytokine transcription in human CD4�CD25� T cells byFoxp3� regulatory T cells: independence of IL-2 consumption, TGF-�,and various inhibitors of TCR signaling. J Immunol 2007;179:3578-3587.

3. Cani PD, Amar J, Iglesias MA, Poggi M, Knauf C, Bastelica D, et al.Metabolic endotoxemia initiates obesity and insulin resistance. Diabetes2007;56:1761-1772.

4. Fukui K. Relation of endotoxin, endotoxin binding proteins and macro-phages to severe alcoholic liver injury and multiple organ failure. AlcoholClin Exp Res 2005;29:172S–179S.

5. Goncalves S, Pecoits-Filho R, Perreto S, Barberato SH, Stinghen AEM,Lima EGA, et al. Association between renal function, volume status andendotoxaemia in chronic kidney disease patients. Nephrol Dial Transplant2006;21:2788-2794.

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