Hepatitis: Gershwin ME

Ishibashi H, Komori A, Shimoda S, Gershwin ME. · Clinical Research Center, National Hospital Organization (NHO), Nagasaki Medical Center, and Department of Hepatology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan. · Semin Liver Dis. · Pubmed #17520519 No free full text.

Abstract: The principle of therapy for chronic inflammatory liver diseases is the removal of causal agents. For autoimmune liver diseases, however, total removal of causal agents and immune cells is impossible. Therefore, autoimmune liver diseases are presently treated by suppression of the immune response. Autoimmune hepatitis is characteristically responsive to corticosteroids, often used in combination with azathioprine to obtain a steroid-sparing effect. For primary biliary cirrhosis, ursodeoxycholic acid is safe and is the first choice for treatment. Treatment of this autoimmune liver disease should also address various symptoms and complications arising from any associated autoimmune diseases, particularly cholestasis and cirrhosis-related complications. For primary sclerosing cholangitis there are no established immunomodulatory therapies, but medical, endoscopic, and surgical treatments are applicable to this disease. Liver transplantation becomes indicated during the eventual end stages of each of these immune-mediated liver diseases.

Berkun Y, Gershwin ME, Shoenfeld Y. · No affiliation provided · Isr Med Assoc J. · Pubmed #15847210 links to  free full text

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Selmi C, Battezzati PM, Gershwin ME, Tishler M, Shoenfeld Y. · No affiliation provided · Autoimmun Rev. · Pubmed #15722253 No free full text.

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Gershwin ME, Mackay IR. · Division of Rheumatology, Allergy and Clinical Immunology, University of California at Davis School of Medicine, Davis, CA 95616, USA. · Hepatology. · Pubmed #18098322 No free full text.

Abstract: The most difficult issue in autoimmunity remains etiology. Although data exist on effector mechanisms in many autoimmune diseases, the underlying cause or causes are still generically ascribed to genetics and environmental influences. Primary biliary cirrhosis (PBC) is considered a model autoimmune disease because of its signature antimitochondrial autoantibody (AMA), the homogeneity of clinical characteristics, and the specificity of biliary epithelial cell (BEC) pathology. Twenty years ago, we reported the cloning and identification of the E2 component of pyruvate dehydrogenase (PDC-E2) as the immunodominant autoantigen of PBC, allowing for vigorous dissection of T and B lymphocyte responses against PDC-E2 and development of several valid experimental models. There has also been considerable study of the biology of BECs, which has included the unique properties of apoptosis in which there is exposure of PDC-E2 to the effector processes of the immune system. In this review, we present these data in the context of our proposal that the proximal cause of PBC is autoimmunity directed against well-identified mitochondrially located autoantigens in individuals with inherited deficits of immune tolerance. We present these data under the umbrella of convenient truths that support this thesis as well as some inconvenient truths that are not readily accommodated by current theory. CONCLUSION: We emphasize that the potential initiator of PBC includes inter alia particular environmental xenobiotics; pathogenesis is aided and abetted by genetic weaknesses in mechanisms of immune regulation; and subsequent multilineage immunopathology impacts upon uniquely susceptible BECs to culminate clinically in the chronic autoimmune cholangiolitis of PBC.

Moritoki Y, Lian ZX, Ohsugi Y, Ueno Y, Gershwin ME. · Division of Rheumatology, Allergy and Clinical Immunology, University of California at Davis School of Medicine, 451 E. Health Sciences Drive, Suite 6510, Davis, CA 95616, USA. · Autoimmun Rev. · Pubmed #16920571 No free full text.

Abstract: Autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) are the three major autoimmune diseases affecting the liver. They are all characterized by the presence of a variety of autoantibodies, some of which are found in all three diseases, whereas others are restricted to one or two of them or are even specific for the particular disease. In this review we will first provide details of the serological features of these three autoimmune diseases that target the liver. In addition, we will highlight the possible pathogenic roles of autoreactive B cells, focusing on their immunological functions as autoantibody producing cells and as antigen-presenting cells for T cell priming. As well, we will describe the contribution of toll-like receptor (TLR) signaling to the activation of autoimmune B cells and the putative role of defects in regulatory T cell function in the development of autoimmune liver diseases.

Selmi C, Lleo A, Zuin M, Podda M, Rossaro L, Gershwin ME. · Division of Rheumatology, Allergy and Clinical Immunology, University of California at Davis School of Medicine, Genome and Biomedical Sciences Facility, 451 E Health Sciences Drive, Suite 6510, Davis, CA 95616, USA. · Curr Opin Investig Drugs. · Pubmed #16729722 No free full text.

Abstract: It is now well accepted that interferon (IFN)alpha plays a critical role in the pathogenesis and perpetuation of specific autoimmune diseases, including systemic lupus erythematosus (SLE), autoimmune thyroid disease and type 1 diabetes. IFNalpha-based treatments are widely used for the treatment of chronic viral infections, particularly chronic hepatitis C virus infection; however, several case reports have emerged describing autoimmune conditions that have developed during IFNalpha therapy. The data support the pathogenic potential of IFNalpha in autoimmunity, although it is clear that genetic and environmental factors are also key to the development of autoimmune conditions. Several points of interaction between IFNalpha and immune effector cells have been experimentally defined, the functional consequences of many of which remain poorly understood. This review describes the most recent data in support of an important role for IFNalpha in autoimmunity, particularly SLE, and the potential mechanisms by which IFNalpha contributes to immune dysfunction. Future approaches to IFNalpha modulation as a therapeutic strategy for use in the treatment of autoimmune diseases are also discussed.

Ichiki Y, Aoki CA, Bowlus CL, Shimoda S, Ishibashi H, Gershwin ME. · Division of Rheumatology, Allergy and Clinical Immunology, University of California at Davis School of Medicine, TB192, One Shields Avenue, Davis, CA 95616, USA. · Autoimmun Rev. · Pubmed #15990080 No free full text.

Abstract: T cells play a central role in the immunopathogenesis of AIH. Until recently CD4+ T cells were thought to be critical for disease development, increasing evidence has shown that CD8+ T and gammadelta T cells also play a significant role. The predisposition of certain HLA genotypes to AIH as well as the clonal expansion of a limited number of T cell receptors suggests that the presentation of a self-antigen or a molecular mimic may be responsible for the initiation of the immune response. Given the association of AIH with viral hepatitis, it is thought that the loss of tolerance begins with an infection of hepatocytes and subsequent cytolysis by CD8+ T cells. The presentation of self-antigens or molecular mimics leads to activation and clonal expansion of T cells; this process may be increased by impaired regulatory T cells and a defect in apoptosis. Ultimately T cells initiate B cell production of autoantibodies, proinflammatory cytokines and finally hepatocyte cytotoxicity.

Ichiki Y, He XS, Shimoda S, Ishibashi H, Keeffe EB, Rossaro L, Gershwin ME. · Division of Rheumatology, Allergy and Clinical Immunology, University of California at Davis School of Medicine, TB192, One Shields Avenue, Davis, CA 95616, USA. · Autoimmun Rev. · Pubmed #15722254 No free full text.

Abstract: T cells are involved in the pathogenesis of important liver diseases including both autoimmune liver diseases and viral hepatitis. In addition to playing a crucial role in the control of hepatitis viruses, T cell responses are also responsible for the liver injury during acute and chronic phases of viral hepatitis. In this article, we reviewed current literature on T cell immunity to hepatitis B and C viruses. In addition, antigen presenting cells that are critical for T cell immunity against these viruses are also discussed. This will provide insights to the understanding of T cell immunity in autoimmune liver diseases due to the similar role of T cells in autoimmune liver diseases and viral hepatitis.

Borchers AT, Keen CL, Shoenfeld Y, Silva J, Gershwin ME. · Division of Rheumatology, Allergy and Clinical Immunology, University of California at Davis, Davis, CA, USA. · J Investig Allergol Clin Immunol. · Pubmed #12530114 No free full text.

Abstract: Vaccinations are invaluable in protection from a wide variety of diseases that can cause substantial morbidity and mortality. Although a rare complication of vaccination, autoimmune disorders represent one of these morbidities. Recently, widespread public concern has arisen from case reports suggesting that--similar to what has been observed after natural viral infections--there might be an association between specific immunizations and autoimmune diseases. Herein we address the biological plausibility of such a connection, focusing particularly on the examples of hepatitis B, rubella, and measles-mumps-rubella (MMR) vaccinations, and the autoimmune diseases they are potentially associated with. Our review of the available data suggests that, for the general population, the risk: benefit ratio is overwhelmingly in favor of vaccinations. However, the possibility cannot be ruled out that, in genetically susceptible individuals, vaccination can result in the unmasking of an autoimmune disease triggered by the immunization. We also critically examine the existing data suggesting a link between immunization against MMR and autism, and briefly discuss the controversial evidence pointing to a possible relationship between mercury exposure from vaccines and autistic disorders. There is a continued urgent need for rigorously designed and executed studies addressing these potential associations, although the use of vaccinations remains a critical public health tool for protection against infectious disease.

Tanaka A, Miyakawa H, Luketic VA, Kaplan M, Storch WB, Gershwin ME. · The Institute for Adult Diseases, Asahi Life Foundation, Tokyo, Japan. · Cell Mol Biol (Noisy-le-grand). · Pubmed #12030434 No free full text.

Abstract: Anti-mitochondrial antibodies (AMA) are present in sera of approximately 90-95% of patients with primary biliary cirrhosis (PBC) and, thus, constitute one of the most important diagnostic criteria for this disease. The major mitochondrial autoantigens have been identified, cloned, and sequenced and the immunological features of AMA, including their antigen specificities and epitopes, have been well characterized. In clinical laboratories, indirect immunofluorescence (IIF) microscopy is routinely employed for the detection of AMA mainly because of technical simplicity and cost effectiveness. However, IIF lacks both specificity and sensitivity, and in up to 10% of patients diagnosed with PBC based on standard diagnostic criteria, AMA cannot be detected by IIF. In some of these patients, AMA aredetectable by more sensitive techniques, such as enzyme-linked immunosorbent assays (ELISAs) or SDS-PAGE followed by immunoblotting. Nonetheless, there are patients whose sea are negative for AMA by any of these methods despite clinical, biochemical, and histological findings that are diagnostic for PBC. Some have argued that AMA-positive and AMA-negative PBC represent two distinct entities, but recent evidence supports the view that they are clinically and biochemically quite similar. The situation is further complicated by the fact that AMA, even those recognizing the major PBC autoantigens, are also present in a variety of other liver diseases. In addition, patients exhibiting the clinical, histological, and biochemical features of both PBC and autoimmune hepatitis, the so-called 'overlap syndrome,' are not uncommon. In conclusion, AMA status, though invaluable in establishing and confirming the diagnosis of PBC in > or =90% of PBC patients, is not sufficient by itself to allow the differential diagnosis of liver diseases. The choice of therapeutic regimen should, therefore, be based on a combination of serological, biochemical and histological findings, rather than AMA status alone.

Kita H, Mackay IR, Van De Water J, Gershwin ME. · Division of Rheumatology, Allergy, and Clinical Immunology, University of California Davis School of Medicine, Davis, California 95616, USA. · Gastroenterology. · Pubmed #11313320 No free full text.

Abstract: Immunologic injury in the liver involves immigrant T and B lymphocytes and a resident lymphoid population that comprises distinct lymphocytic cells and accessory cells. The forerunner to autoimmunity is breaching of natural self-tolerance and hence the disruption of a fundamental property of the immune system. Such breaching occurs by processes that include inflammatory activation of immunocytes and macrophages, spillage of intracellular constituents, and epitope mimicry by constituents of microorganisms, with these acting on a genetically conditional phenotype; compounding factors include aberrations of apoptosis, whether insufficient or excess. The downstream end requires specifically directed inflammatory leukocyte traffic as an essential component of autoimmune expressions in the liver. The culmination is an orchestrated attack on hepatocytes or biliary epithelial cells by multiple effector pathways. Progress in type 1 autoimmune hepatitis still requires knowledge of a disease-specific autoantigen(s) involved in T-cell reactivity, although such knowledge in type 2 autoimmune hepatitis, in which the known autoantigen is cytochrome P4502D6, has not yet been integrated into a clearly defined scheme of pathogenesis. For PBC there has been a very promising amalgamation of molecular knowledge of the mitochondrial autoantigens. Future insights require deeper analysis of molecular, genetic, macroenvironmental, and microenvironmental elements in predisposition.

Van de Water J, Ishibashi H, Coppel RL, Gershwin ME. · Division of Rheumatology, Allergy and Clinical Immunology, University of California at Davis School of Medicine, 95616, USA. · Hepatology. · Pubmed #11283838 No free full text.

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Siekmann JH, Allen LH, Watnik MR, Nestel P, Neumann CG, Shoenfeld Y, Peter JB, Patnik M, Ansari AA, Coppel RL, Gershwin ME. · Department of Nutrition, University of California, Davis 95616, USA. · Am J Clin Nutr. · Pubmed #12499348 links to  free full text

Abstract: BACKGROUND: Undernutrition is widely perceived to affect the development of an effective immune system. OBJECTIVE: We used a mini-analysis system to quantitate antibody titers and evaluate the sera of 200 Kenyan schoolchildren for antibodies to Helicobacter pylori [isotypes of immunoglobulins A (IgA), G (IgG), and M (IgM)], hepatitis A virus, rotavirus, tetanus toxoid (IgG), and a panel of recombinant malarial antigens (MSP1(19), MSP2, Ag512, MSP4, and MSP5). DESIGN: Children participated in a school-based feeding intervention with meat, milk, or nonanimal-source foods or in a nonintervention control group. Microvolumes (200 mL) of sera were analyzed at baseline and after 1 y. RESULTS: Nearly all children had elevated titers of antibody to H. pylori, hepatitis A virus, rotavirus, and malaria at the outset, despite a high prevalence of apparent biochemical micronutrient deficiencies and stunting, but many had titers of tetanus toxoid IgG antibodies below the protective concentration. Children with low hemoglobin had a greater proportion of elevated H. pylori IgM antibody titers at baseline, which suggests that current infection with H. pylori may be associated with anemia. Compared with the control subjects, only the group eating meat had a significant increase in H. pylori IgM antibodies during the intervention (P = 0.019). No other group comparisons with the control subjects were statistically significant. The additional finding that the sera of some children showed inadequate tetanus-protective antibodies, despite immunization, suggests that the vaccination program was suboptimal. CONCLUSIONS: A large battery of immune assays can be performed on microvolumes of sera. Furthermore, despite evidence of malnutrition, children do develop significant antibody-mediated responses to common pathogens.

Agmon-Levin N, Ram M, Barzilai O, Porat-Katz BS, Parikman R, Selmi C, Gershwin ME, Anaya JM, Youinou P, Bizzaro N, Tincani A, Tzioufas AG, Cervera R, Stojanovich L, Martin J, Gonzalez-Gay MA, Valentini G, Blank M, SanMarco M, Rozman B, Bombardieri S, De Vita S, Shoenfeld Y. · Center for Autoimmune Diseases, Chaim Sheba Medical Center, Tel-Hashomer 52621, Israel. · J Autoimmun. · Pubmed #19356903 No free full text.

Abstract: OBJECTIVE: To evaluate the prevalence of serum antibodies against hepatitis C virus and other infectious agents in a large cohort of well-characterized patients with autoimmune diseases (AID). METHODS: We utilized 1322 sera from patients with 18 different AID and 236 sera from healthy controls from the same countries and with similar age and sex distribution. All sera were tested for the presence of serum anti-hepatitis C virus (HCV) antibodies as well as antibodies directed at other infectious agents and autoantibodies. RESULTS: Anti-HCV antibody was detected in 115/1322 (8.7%) of patients with AID and 0.4% of matched healthy controls (P < 0.0001). The prevalence of anti-HCV antibody was significantly higher in 7/18 different AID (i.e. cryoglobulinemia, mixed cryoglobulinemia pemphigus vulgaris, vasculitis, secondary anti-phospholipid syndrome, Hashimoto's thyroiditis, and inflammatory bowel disease) compared to controls. Patients with AID and serum anti-HCV positivity had an increased prevalence of antibodies against hepatitis B virus, Toxoplasma gondii and Cytomegalovirus as opposed to a lower frequency of serum autoantibodies. CONCLUSIONS: The enhanced prevalence of anti-HCV serum antibodies in AID may suggest a role for HCV in tolerance to breakdown, similarly to its established role in mixed cryoglobulinemia. This immune mediated effect does not rule out the role of other infectious agents.

Park O, Jeong WI, Wang L, Wang H, Lian ZX, Gershwin ME, Gao B. · Section on Liver Biology, Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA. · Hepatology. · Pubmed #19205035 No free full text.

Abstract: Liver fibrosis is a common scarring response to all forms of chronic liver injury and is always associated with inflammation that contributes to fibrogenesis. Although a variety of cell populations infiltrate the liver during inflammation, it is generically clear that CD8 T lymphocytes promote while natural killer (NK) cells inhibit liver fibrosis. However, the role of invariant natural killer T (iNKT) cells, which are abundant in the liver, in hepatic fibrogenesis, remains obscure. Here we show that iNKT-deficient mice are more susceptible to carbon tetrachloride (CCl(4))-induced acute liver injury and inflammation. The protective effect of naturally activated iNKT in this model is likely mediated via suppression of the proinflammatory effect of activated hepatic stellate cells. Interestingly, strong activation of iNKT through injection of iNKT activator alpha-galactosylceramide (alpha-GalCer) accelerates CCl(4)-induced acute liver injury and fibrosis. In contrast, chronic CCl(4) administration induces a similar degree of liver injury in iNKT-deficient and wild-type mice, and only a slightly higher grade of liver fibrosis in iNKT-deficient mice than wild-type mice 2 weeks but not 4 weeks after CCl(4) injection, although iNKT cells are able to kill activated stellate cells. An insignificant role of iNKT in chronic liver injury and fibrosis may be attributable to hepatic iNKT cell depletion. Finally, chronic alpha-GalCer treatment had little effect on liver injury and fibrosis, which is attributable to iNKT tolerance after alpha-GalCer injection. Conclusion: Natural activation of hepatic iNKT cells inhibits, whereas strong activation of iNKT cells by alpha-GalCer accelerates CCl(4)-induced acute liver injury, inflammation, and fibrosis. During chronic liver injury, hepatic iNKT cells are depleted and play a role in inhibiting liver fibrosis in the early stage but not the late stage of fibrosis.

Wei HX, Chuang YH, Li B, Wei H, Sun R, Moritoki Y, Gershwin ME, Lian ZX, Tian Z. · Institute of Immunology, Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, China. · J Immunol. · Pubmed #18981144 No free full text.

Abstract: Regulatory T cells (Tregs), which are characterized by expression of CD4, CD25, and Foxp3, play a crucial role in the control of immune responses to both self and non-self Ags. To date, there are only limited data on their role in physiological and pathological hepatic immune responses. In this study, we examined the role of hepatic Tregs in immune-mediated liver injury by using the murine Con A-induced hepatitis model. Con A treatment was associated with an increased number of Foxp3(+) Tregs in liver but not in spleen. Moreover, the expression levels of Foxp3, CTLA-4, glucocorticoid-induced TNF receptor, as well as the frequency of CD103 of Tregs were increased after Con A injection, being significantly higher in liver than in spleen. Depleting CD25(+) cells aggravated liver injury, whereas adoptively transferring CD25(+) cells or Tregs reduced liver injury in Con A-treated recipients. Con A treatment induced elevated serum levels and hepatic mononuclear mRNA expressions of TGF-beta, which were reduced by Tregs depletion. In addition, anti-TGF-beta mAbs blocked the suppressive function of Tregs from Con A-treated mice in vitro. Finally, TGF-beta receptor II dominant-negative mice, whose T cells express a dominant negative form of TGFbetaRII and therefore cannot respond to TGF-beta, had a higher mortality rate and severer liver injury than normal mice injected with the same dose of Con A. These results indicate that CD4(+)CD25(+) Tregs play an important role in limiting the liver injury in Con A-induced hepatitis via a TGF-beta-dependent mechanism.

Whittingham S, Rowley MJ, Gershwin ME. · Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia. · J Autoimmun. · Pubmed #18502096 No free full text.

Abstract: The 11th Australasian Autoimmunity Workshop was held in Melbourne, Australia from July 6-8, 2007 organized by the Monash University Autoimmunity Network. The workshops, founded by the late Kevin Lafferty, are a chance for Australasians interested in research into autoimmune disease to present and discuss their work. This workshop also was a chance to acknowledge Ian Mackay, a pioneer clinician-scientist who has made major contributions to our understanding of autoimmune diseases. Friends, colleagues and former students attended the Workshop and acknowledged Ian's expertise and mentorship. This edition of the Journal of Autoimmunity pays tribute to Ian Mackay. It features articles from attendees at the workshop, and contributions from some of Ian's past students and past and current collaborators.

Mattner J, Savage PB, Leung P, Oertelt SS, Wang V, Trivedi O, Scanlon ST, Pendem K, Teyton L, Hart J, Ridgway WM, Wicker LS, Gershwin ME, Bendelac A. · Howard Hughes Medical Institute, Committee on Immunology, Department of Pathology, University of Chicago, Chicago, IL 60637, USA. · Cell Host Microbe. · Pubmed #18474357 links to  free full text

Abstract: Humans with primary biliary cirrhosis (PBC), a disease characterized by the destruction of small bile ducts, exhibit signature autoantibodies against mitochondrial Pyruvate Dehydrogenase Complex E2 (PDC-E2) that crossreact onto the homologous enzyme of Novosphingobium aromaticivorans, an ubiquitous alphaproteobacterium. Here, we show that infection of mice with N. aromaticivorans induced signature antibodies against microbial PDC-E2 and its mitochondrial counterpart but also triggered chronic T cell-mediated autoimmunity against small bile ducts. Disease induction required NKT cells, which specifically respond to N. aromaticivorans cell wall alpha-glycuronosylceramides presented by CD1d molecules. Combined with the natural liver tropism of NKT cells, the accumulation of N. aromaticivorans in the liver likely explains the liver specificity of destructive responses. Once established, liver disease could be adoptively transferred by T cells independently of NKT cells and microbes, illustrating the importance of early microbial activation of NKT cells in the initiation of autonomous, organ-specific autoimmunity.

Nakanishi Y, Tsuneyama K, Fujimoto M, Salunga TL, Nomoto K, An JL, Takano Y, Iizuka S, Nagata M, Suzuki W, Shimada T, Aburada M, Nakano M, Selmi C, Gershwin ME. · Department of Diagnostic Pathology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan. · J Autoimmun. · Pubmed #18178378 No free full text.

Abstract: Chronic inflammation is a common theme in a variety of disease pathways, including autoimmune diseases. The pathways of chronic inflammation are well illustrated by nonalcoholic steatohepatitis (NASH), which is of a serious concern due to its increasing prevalence in the westernized world and its direct correlation with lifestyle factors, particularly diet. Importantly, NASH may ultimately lead to the development of hepatocellular carcinoma. We previously reported that injection of monosodium glutamate (MSG) in ICR mice leads to the development of significant inflammation, central obesity, and type 2 diabetes. To directly address the long-term consequences of MSG on inflammation, we have performed serial analysis of MSG-injected mice and focused in particular on liver pathology. By 6 and 12 months of age, all MSG-treated mice developed NAFLD and NASH-like histology, respectively. In particular, the murine steatohepatitis at 12 months was virtually undistinguishable from human NASH. Further, dysplastic nodular lesions were detected in some cases within the fibrotic liver parenchyma. We submit that MSG treatment of mice induces obesity and diabetes with steatosis and steatohepatitis resembling human NAFLD and NASH with pre-neoplastic lesions. These results take on considerable significance in light of the widespread usage of dietary MSG and we suggest that MSG should have its safety profile re-examined and be potentially withdrawn from the food chain.

Oertelt S, Rieger R, Selmi C, Invernizzi P, Ansari AA, Coppel RL, Podda M, Leung PS, Gershwin ME. · Division of Rheumatology, Allergy and Clinical Immunology, University of California at Davis, Davis, CA 95616, USA. · Hepatology. · Pubmed #17326160 No free full text.

Abstract: The antimitochondrial response in primary biliary cirrhosis (PBC) is the most highly directed and specific self-reacting antibody in human immunopathology. Originally, antimitochondrial antibodies (AMAs) were detected by indirect immunofluorescence (IIF) and found in approximately 90% of well-documented patients with PBC. The introduction of recombinant autoantigens and the use of immunoblotting have increased the sensitivity and specificity of AMAs, and they are now considered positive in approximately 95% of patients with PBC. Clearly, accurate autoantibody detection represents one of the fundamental requirements for reliable diagnostics in autoimmunity. To address the 5% of AMA-negative patients with PBC, we have generated and validated a bead assay for the detection of AMA. We enrolled 120 patients with PBC, including a non-random group of 30 rigorously proven AMA-negative patients, 50 healthy subjects, and 74 controls with autoimmune diseases (18 with primary sclerosing cholangitis, 16 with autoimmune hepatitis, and 40 with systemic lupus erythematosus). Individual bead assays were done with the three mitochondrial autoantigens, PDC-E2, BCOADC-E2, and OGDC-E2. As expected, 90 of 90 previously known AMA-positive patients remained positive with this assay but, interestingly, 20% of the rigorously defined AMA-negative patient group had antibodies to one or more of the mitochondrial autoantigens. Furthermore, 100% of these newly detected AMA-positive patients were anti-nuclear antibody (ANA) positive. CONCLUSION: The development of this assay reflects the potential for automated detection with rapid and reliable assaying and further highlights the diminished number of truly AMA-negative PBC patients.

Miyakawa H, Tanaka A, Selmi C, Hosoya N, Mataki N, Kikuchi K, Kato T, Arai J, Goto T, Gershwin ME. · Fourth Department of Internal Medicine, Teikyo University School of Medicine, Kanagawa 213-8507, Japan. · Clin Dev Immunol. · Pubmed #17162370 links to  free full text

Abstract: Antimitochondrial antibodies (AMA) are the serum hallmark of primary biliary cirrhosis (PBC). However, AMA-positivity can be found in non-PBC sera when lower dilutions are used, thus raising issues about the specificity and sensitivity of the test. AMA reacts primarily with the lipoylated domains of pyruvate dehydrogenase-E2 (PDC-E2) which is highly conserved across species, including bacteria. We studied 77 serum samples, including 24 from patients with anti-PDC-E2-positive PBC and 53 controls (16 with autoimmune hepatitis (AIH), 10 with primary sclerosing cholangitis (PSC), and 27 healthy individuals) for their reactivities at serial dilutions (1:10, 1:20 and 1:40) against Escherichia coli DH5 alpha lysate overexpressing human PDC-E2 using immunoblotting (IB). A murine anti-human PDC-E2 monoclonal antibody (mAB) was used as control. We further studied positive sera using adsorption with a synthetic E. coli peptide sharing similarity with human PDC-E2. Finally, we verified whether a unique buffer for E. coli preparation could reduce non-specific serum reactivity. Results demonstrated that 100% of anti-PDC-E2-positive PBC and up to 38% of control sera at 1:10 dilution recognized E. coli PDC-E2 at IB while dilution tests indicated that the overall potency of PBC reactivity was 100-fold higher compared to controls. In fact, a subgroup (20-38%) of non-PBC sera were positive at low titers but lost the reactivity when absorbed with the synthetic E. coli peptide. Finally, our unique buffer reduced the reactivity of non-PBC sera as measured by ELISA. In conclusion, we demonstrated that weak cross-reactivity with E. coli PDC-E2 occurs in non-PBC sera at lower dilutions and that such reactivity is not due to AMA-positivity. The use of a specific buffer might avoid the risk of false positive AMA determinations when E. coli-expressed recombinant antigens are used.

Watanabe N, Takashimizu S, Shiraishi K, Kagawa T, Nishizaki Y, Mine T, Akatsuka A, Selmi C, Gershwin ME. · Division of Gastroenterology, Department of Internal Medicine, University School of Medicine, Kanagawa, Japan. · Eur J Gastroenterol Hepatol. · Pubmed #16894319 No free full text.

Abstract: Histological and clinical features of syncytial giant cell hepatitis (GCH) are rarely observed in adults, and the disease has been associated with several autoimmune disorders and drug reactions. We describe here the case of a 62-year-old woman who presented with evidence of severe acute hepatocellular injury and cholestasis. Serum work-up demonstrated antimitochondrial antibodies specific for primary biliary cirrhosis (PBC) autoantigens, whereas markers of viral infection including hepatitis viruses, paramyxovirus and measles virus were negative. Liver histology revealed the presence of multinucleated hepatocellular giant cells in the parenchymal areas surrounding bridging necrosis. Importantly, damaged interlobular bile ducts were also observed within the lymphocyte-infiltrated portal tracts. Further study using transmission electron microscopy demonstrated the presence of filamentous strands and particles resembling paramyxovirus nucleocapsids in the cytoplasm of syncytial giant cells. To our knowledge, this is the first case of PBC with histological and clinical evidence of syncytial GCH in an adult, and we submit that it might provide novel clues in the enigma of PBC pathogenesis.

Lan RY, Cheng C, Lian ZX, Tsuneyama K, Yang GX, Moritoki Y, Chuang YH, Nakamura T, Saito S, Shimoda S, Tanaka A, Bowlus CL, Takano Y, Ansari AA, Coppel RL, Gershwin ME. · Division of Rheumatology, Allergy, and Clinical Immunology, University of California--Davis, Davis, CA 95616, USA. · Hepatology. · Pubmed #16557534 No free full text.

Abstract: CD4+CD25high regulatory T cells (Tregs) play a critical role in self-tolerance, as seen in murine autoimmunity. Studies on Tregs in human autoimmunity have focused primarily on peripheral blood samples. A study targeting diseased tissue should identify direct relationships between Tregs and autoimmunity. Peripheral blood samples were collected from 91 patients with primary biliary cirrhosis (PBC), 28 immediate relatives, and 41 healthy controls, and Treg frequencies were determined as a percentage of CD4+CD25high T cells in CD4+TCR-alphabeta+ T cells. A tissue-targeted determination of frequency and distribution of FoxP3+ Tregs was also performed on 90 different liver tissue specimens exhibiting PBC (n = 52), chronic hepatitis C (CHC) (n = 30), and autoimmune hepatitis (AIH) (n = 8). Treg suppression studies were performed on 50 PBC patients and 27 controls. Patients with PBC demonstrated a relative reduction of Tregs compared with controls (P < .0002). Interestingly, a deficiency in CD4+CD25+ Tregs was also found in the daughters and sisters of PBC patients compared with controls (P < .0007). However, functional studies did not reveal a global PBC Treg defect. The level of FoxP3-expressing Tregs was markedly lower in affected PBC portal tracts compared with CHC and AIH (P < .001). In addition, the CD8+T cell/FoxP3+ Treg ratio was significantly higher in livers of late-stage PBC compared with those of CHC (P < .001) and early-stage AIH (P < .001). In conclusion, these data provide support for a genetic modulation of Treg frequency and illustrate the role Tregs play in the loss of tolerance in PBC.

Invernizzi P, Miozzo M, Battezzati PM, Bianchi I, Grati FR, Simoni G, Selmi C, Watnik M, Gershwin ME, Podda M. · Department of Internal Medicine University of Milan, Via di Rudinì 8, 20142 Milan, Italy. · Lancet. · Pubmed #14975617 No free full text.

Abstract: The mechanisms that cause the female predominance of primary biliary cirrhosis (PBC) are uncertain, but the X chromosome includes genes involved in immunological tolerance. We assessed the rate of X monosomy in peripheral white blood cells from 100 women with PBC, 50 with chronic hepatitis C, and 50 healthy controls, by fluorescence in-situ hybridisation. Frequency of X monosomy increased with age in all groups, but was significantly higher in women with PBC than in controls (p<0.0001); age-adjusted back-transformed mean frequencies were 0.050 (95% CI 0.046-0.055) in women with PBC, 0.032 (0.028-0.036) in those with chronic hepatitis C, and 0.028 (0.025-0.032) in controls. We suggest that haploinsufficiency for specific X-linked genes leads to female susceptibility to PBC.

Muratori P, Muratori L, Gershwin ME, Czaja AJ, Pappas G, MacCariello S, Granito A, Cassani F, Loria P, Lenzi M, Bianchi FB. · Department of Internal Medicine, Cardioangiology, Hepatology, Alma Mater Studiorum - University of Bologna, Bologna, Italy. · Clin Exp Immunol. · Pubmed #14678277 links to  free full text

Abstract: Anti-mitochondrial antibody (AMA) is considered the serological hallmark of primary biliary cirrhosis (PBC), but may be missing in a proportion of these patients. We assessed sensitivity and specificity of the currently available techniques for AMA detection in a large series of PBC patients and controls, and analysed their clinical and immunological features according to the AMA status. By indirect immunofluorescence on rat tissue sections and HEp-2 cells, Western immunoblot with bovine submitochondrial particles, and two ELISAs with AMA-specific recombinant proteins, we evaluated the presence of AMA in 127 PBC patients, 166 patients with type 1 autoimmune hepatitis and 100 with non alcoholic fatty liver disease. In PBC patients Western immunoblot detects AMA significantly more often than indirect immunofluorescence on HEp-2 cells (85%versus 72%, P = 0.02) or rodent tissue sections (71%, P = 0.01); both ELISAs are only slightly less sensitive than Western immunoblot (81% and 78%). Ten patients with non alcoholic fatty liver disease were AMA-positive by indirect immunofluorescence, but none recognized AMA-specific epitopes in Western immunoblot or in ELISAs. Twelve patients with type 1 autoimmune hepatitis were AMA-positive by indirect immunofluorescence, but only 6 (3.6%) reacted by Western immunoblot and ELISAs. Western immunoblot or ELISA should be regarded as first-line assay for the detection of AMA. Up to 15% of PBC patients are consistently AMA-negative, yet they share the same clinical, biochemical and histological features of AMA-positive PBC. Detection of AMA in type 1 autoimmune hepatitis might identify a subset of patients at risk of developing a hepatitic/cholestatic syndrome.