A multifaceted imbalance of T cells with regulatory function characterizes type 1 autoimmune hepatitis.

UNLABELLED: Immunotolerance is maintained by regulatory T cells (Tregs), including CD4(+)CD25(hi), CD8(+)CD28(-), gammadelta, and CD3(+)CD56(+) [natural killer T (NKT)] cells. CD4(+)CD25(hi) cells are impaired in children with autoimmune hepatitis (AIH). Little is known about Tregs in adults with AIH. The aim of this study was to investigate the frequency and function of Treg subsets in adult patients with AIH during periods of active disease and remission. Forty-seven AIH patients (16 with active disease and 31 in remission) and 28 healthy controls were studied. Flow cytometry was used to evaluate surface markers and function-related intracellular molecules in gammadelta, CD8(+)CD28(-), NKT, and CD4(+)CD25(hi) cells. CD4(+)CD25(hi) T cell function was determined by the ability to suppress proliferation and interferon gamma (IFN-gamma) production by CD4(+)CD25(-) target cells. Liver forkhead box P3-positive (FOXP3(+)) cells were sought by immunohistochemistry. In AIH patients, particularly during active disease, CD4(+)CD25(hi) T cells were fewer, expressed lower levels of FOXP3, and were less effective at inhibiting target cell proliferation versus healthy controls. Moreover, although the numbers of CD8(+)CD28(-) T cells were similar in AIH patients and healthy controls, NKT cells were numerically reduced, especially during active disease, and produced lower quantities of the immunoregulatory cytokine interleukin-4 versus controls. In contrast, gammadelta T cells in AIH patients were more numerous versus healthy controls and had an inverted Vdelta1/Vdelta2 ratio and higher IFN-gamma and granzyme B production; the latter was correlated to biochemical indices of liver damage. There were few FOXP3(+) cells within the portal tract inflammatory infiltrate. CONCLUSION: Our data show that the defect in immunoregulation in adult AIH is complex, and gammadelta T cells are likely to be effectors of liver damage.

PML nuclear body component Sp140 is a novel autoantigen in primary biliary cirrhosis.

OBJECTIVES: Some patients with primary biliary cirrhosis (PBC) have antinuclear antibodies (ANAs). These ANAs include the "multiple nuclear dots" (MND) staining pattern, targeting promyelocytic leukemia protein (PML) nuclear body (NB) components, such as "speckled 100-kD" protein (Sp100) and PML. A new PML NB protein, designated as Sp140, was identified using serum from a PBC patient. The aim of this study was to analyze the immune response against Sp140 protein in PBC patients. METHODS: We studied 135 PBC patients and 157 pathological controls with type 1 autoimmune hepatitis, primary sclerosing cholangitis, and systemic lupus erythematosus. We used indirect immunofluorescence and a neuroblastoma cell line expressing Sp140 for detecting anti-Sp140 antibodies, and a commercially available immunoblot for detecting anti-Sp100 and anti-PML antibodies. RESULTS: Anti-Sp140 antibodies were present in 20 (15%) PBC patients but not in control samples, with a higher frequency in antimitochondrial antibody (AMA)-negative cases (53 vs. 9%, P<0.0001). Anti-Sp140 antibodies were found together with anti-Sp100 antibodies in all but one case (19 of 20, 90%) and with anti-PML antibodies in 12 (60%) cases. Anti-Sp140 positivity was not associated with a specific clinical feature of PBC. CONCLUSIONS: Our study identifies Sp140 as a new, highly specific autoantigen in PBC for the first time. The very frequent coexistence of anti-Sp140, anti-Sp100 and anti-PML antibodies suggests that the NB is a multiantigenic complex in PBC and enhances the diagnostic significance of these reactivities, which are particularly useful in AMA-negative cases.

The serological profile of the autoimmune hepatitis/primary biliary cirrhosis overlap syndrome.

OBJECTIVES: During the last decade patients with concomitant clinical, biochemical, immunoserological, and histological features of both autoimmune hepatitis (AIH) and primary biliary cirrhosis (PBC) were sporadically described, but definite diagnostic criteria and specific serological markers to support the diagnosis of AIH/PBC overlap syndrome (AIH/PBC OS) are still lacking. METHODS: Clinical, biochemical, and histological features, autoantibody profile, and treatment response of 15 patients with coexistent hepatitic and cholestatic liver damage, all fulfilling strict diagnostic criteria for both AIH and PBC, were compared with those of 120 patients with pure PBC and 120 patients with pure AIH. RESULTS: At diagnosis, the AIH/PBC OS patients' median age was 51 years, similar to that of the PBC patients (52 years, P=NS), but significantly higher than that of the AIH patients (40 years, P=0.04). Anti-dsDNA antibodies were detected in 60% of AIH/PBC OS patients, but only in 4% of PBC patients and 26% of AIH patients (P<0.0001 and 0.01, respectively). Double positivity for antimitochondrial antibodies (AMA) and anti-dsDNA was present in 47% of those with AIH/PBC OS, but only in 2% of the pathological controls (P<0.0001; specificity: 98; 95% confidence interval (CI): 97-99.2; positive likelihood ratio: 28; 95% CI: 9.8-79.4). Combined therapy (ursodeoxycholic acid (UDCA) plus steroids) achieved biochemical response in 77% of AIH/PBC OS patients. CONCLUSIONS: Concomitant AMA/anti-dsDNA seropositivity can be considered the serological profile of AIH/PBC OS. The combination of UDCA and steroids is effective in achieving persistent biochemical amelioration in most AIH/PBC OS patients.

Diagnosis and therapy of autoimmune hepatitis.

Autoimmune hepatitis (AIH) is a chronic progressive hepatitis, characterized by interface hepatitis with lymphoplasmacellular infiltrates on liver biopsy, high serum globulin level and circulating autoantibodies. It is classified into two types, according to autoantibody profile: type 1 is characterized by anti-nuclear (ANA) and/or anti-smooth muscle (SMA) antibodies; type 2 by anti-liver kidney microsomal type 1 (anti-LKM-1) antibodies. AIH affects all ages, may be asymptomatic, frequently has an acute onset, and can present as fulminant hepatitis. The diagnosis of AIH is based on a scoring system codified by an international consensus. Corticosteroids alone or in conjunction with azathioprine is the treatment of choice in patients with AIH and results in remission induction in over 80% of patients. Alternative proposed strategies in patients who have failed to achieve remission on standard therapy or patients with drug toxicity include the use of cyclosporine, tacrolimus, budesonide or mycophenolate mofetil. Liver transplantation is the treatment of choice in managing decompensated disease, however AIH can recur or develop de novo after liver transplantation.

Autoimmune hepatitis in Italy: the Bologna experience.

BACKGROUND/AIMS: Autoimmune hepatitis affects mainly women. It is subdivided into type 1 and type 2 according to the autoantibody profile and without immunosuppression usually evolves to cirrhosis and end-stage liver failure. METHODS: We evaluated clinical, biochemical, immunological and genetic features and treatment response of 163 consecutive Italian patients with autoimmune hepatitis. RESULTS: At diagnosis, type 1 autoimmune hepatitis showed more inflamed liver histology and more pronounced cholestasis, whereas type 2 was more common in children. Male and female patients shared similar clinical, biochemical and immunological features. Of 89 patients with 5-year follow-up or longer, 23 patients irrespective of presenting clinical, biochemical and immunological features achieved complete remission (normal transaminases and gammaglobulin levels) which was maintained with minimal steroid dosage; attempt at treatment withdrawal led to disease exacerbation. Complete responders had more often HLA DRB1*0401 (p = 0.011) and their risk of disease progression was lower (p < 0.0001). CONCLUSIONS: Type 1 and type 2 autoimmune hepatitis is one and the same disease. Autoimmune hepatitis has similar features in male and female patients. HLA DRB1*0401 positive patients are more likely to achieve complete remission. Continuous low-dose steroids are necessary to maintain remission, significantly reducing the risk of disease progression.

Clinical features and effect of antiviral therapy on anti-liver/kidney microsomal antibody type 1 positive chronic hepatitis C.

BACKGROUND/AIMS: Anti-liver/kidney microsomal antibody type 1 (anti-LKM1), a serological marker of type 2 autoimmune hepatitis, is also detected in a small proportion of patients with hepatitis C. This study aimed to evaluate clinical features and effect of antiviral therapy in patients with hepatitis C who are anti-LKM1 positive. METHODS: Sixty consecutive anti-LKM1 positive and 120 age and sex-matched anti-LKM1 negative chronic hepatitis C patients were assessed at diagnosis and during follow-up. Of these, 26 anti-LKM1 positive and 72 anti-LKM1 negative received antiviral therapy. Anti-LKM1 was detected by indirect immunofluorescence and immunoblot. Number of HCV-infected hepatocytes and intrahepatic CD8+ lymphocytes was determined by immunohistochemistry. RESULTS: At diagnosis anti-LKM1 positive patients had higher IgG levels and more intrahepatic CD8+ lymphocytes (p 0.022 and 0.046, respectively). Viral genotypes distribution and response to therapy were identical. Hepatic flares during antiviral treatment only occurred in a minority of patients in concomitance with anti-LKM1 positivity. CONCLUSIONS: Immune system activation is more pronounced in anti-LKM1 positive patients with hepatitis C, possibly representing the expression of autoimmune mechanisms of liver damage. Antiviral treatment is as beneficial in these patients as in anti-LKM1 negative patients, and the rare necroinflammatory flares are effectively controlled by corticosteroids, allowing subsequent resumption of antiviral therapy.

Multiple nuclear dots and rim-like/membranous IgG isotypes in primary biliary cirrhosis.

Anti nuclear (ANA) immunomorphological patterns such as multiple nuclear dots (MND) and rim-like/membranous (RL/M) are considered highly specific but little sensitive for primary biliary cirrhosis (PBC) diagnosis. To evaluate frequency and clinical significance of MND and RL/M in PBC patients when investigated at the level of immunoglobulin G isotypes. MND and RL/M pattern have been tested in 141 PBC sera and 230 pathological controls using HEp-2 cells as substrate and anti- total IgG and individual IgG subclasses (IgG1, IgG2, IgG3, IgG4) as specific antisera. One hundred and fourteen of 141 (80%) PBC patients had RL/M or MND pattern when IgG subclasses were used as revealing reagents (vs. 34% when anti total IgG were used, p < 0.0001). The prevalent isotype was IgG1 for RL/M, and IgG2 for MND pattern. None of controls was positive. No clinical differences in terms of severity and outcome of disease have been observed in PBC patients positive for MND and RL/M when investigated with IgG isotypes. The research for RL/M and MND pattern at level of IgG isotype determines a wide gain in terms of sensitivity without a loss of specificity. In Italian PBC patients MND and RL/M pattern did not seem to characterize any subgroup of patients with a poorer prognosis.

Simplified criteria for the diagnosis of autoimmune hepatitis.

UNLABELLED: Diagnosis of autoimmune hepatitis (AIH) may be challenging. However, early diagnosis is important because immunosuppression is life-saving. Diagnostic criteria of the International Autoimmune Hepatitis Group (IAIHG) were complex and purely meant for scientific purposes. This study of the IAIHG aims to define simplified diagnostic criteria for routine clinical practice. Candidate criteria included sex, age, autoantibodies, immunoglobulins, absence of viral hepatitis, and histology. The training set included 250 AIH patients and 193 controls from 11 centers worldwide. Scores were built from variables showing predictive ability in univariate analysis. Diagnostic value of each score was assessed by the area under the receiver operating characteristic (ROC) curve. The best score was validated using data of an additional 109 AIH patients and 284 controls. This score included autoantibodies, immunoglobulin G, histology, and exclusion of viral hepatitis. The area under the curve for prediction of AIH was 0.946 in the training set and 0.91 in the validation set. Based on the ROC curves, two cutoff points were chosen. The score was found to have 88% sensitivity and 97% specificity (cutoff > or =6) and 81% sensitivity and 99% specificity (cutoff > or =7) in the validation set. CONCLUSION: A reliable diagnosis of AIH can be made using a very simple diagnostic score. We propose the diagnosis of probable AIH at a cutoff point greater than 6 points and definite AIH 7 points or higher.

Antimitochondrial antibodies and other antibodies in primary biliary cirrhosis: diagnostic and prognostic value.

Antimitochondrial antibodies (AMA) are the serologic cornerstone in the diagnosis of primary biliary cirrhosis (PBC), even if they are not detectable in a proportion of patients, notwithstanding the most sensitive and sophisticated technologies used. To fill in the serologic gap in AMA-negative PBC, there is sound evidence to consider antinuclear antibody (ANA) patterns, such as anti-multiple nuclear dots and anti-membranous/rim-like, as PBC-specific surrogate hallmarks of the disease, and their detection can be considered virtually diagnostic. Furthermore, particular ANA specificities, such as anti-gp210, anti-p62, anticentromere antibodies, and anti-dsDNA, may provide additional diagnostic and prognostic information.

Autoimmune liver disease 2007.

Autoimmune liver disease (ALD) includes a spectrum of diseases which comprises both cholestatic and hepatitic forms: autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC), primary sclerosing cholangitis (PSC) and the so called "overlap" syndromes where hepatitic and cholestatic damage coexists. All these diseases are characterized by an extremely high heterogeneity of presentation, varying from asymptomatic, acute (as in a subset of AIH) or chronic (with aspecific symptoms such as fatigue and myalgia in AIH or fatigue and pruritus in PBC and PSC). The detection and characterization of non organ specific autoantibodies plays a major role in the diagnostic approach of autoimmune liver disease; anti nuclear reactivities (ANA) and anti smooth muscle antibodies (SMA) mark type 1 AIH, liver kidney microsomal antibody type 1 (LKM1) and liver cytosol type 1 (LC1) are the serological markers of type 2 AIH; antimitochondrial antibodies (AMA) are associated with PBC, while no specific marker is found in PSC, since anticytoplasmic neutrophil antibodies with perinuclear pattern (atypical p-ANCA or p-ANNA) are also detected in a substantial proportion of type 1 AIH cases. Treatment options rely on immunosoppressive therapy (steroids and azathioprine) in AIH and on ursodeoxycholic acid in cholestatic conditions; in all these diseases liver transplantation remains the only therapeutical approach for the end stage of liver disease.

Usefulness of antibodies to deamidated gliadin peptides in celiac disease diagnosis and follow-up.

The prevalence of the recently described deamidated gliadin peptide antibodies was compared with that of the routinely used antigliadin, antiendomysial, and tissue transglutaminase antibodies in the sera of 128 untreated celiac patients and 134 controls. Sensitivity and specificity for celiac disease were 83.6 and 90.3% for IgA and 84.4 and 98.5% for IgG antibodies to deamidated gliadin peptides. The new test displayed higher diagnostic accuracy than antigliadin antibodies and, although less sensitive than antiendomysial and tissue transglutaminase antibodies, showed significantly higher specificity than tissue transglutaminase antibodies (P < 0.001). Persistence of peptide antibodies after gluten withdrawal was an expression of low compliance with the diet and of the lack of improvement of the intestinal mucosa. The combined use of tissue transglutaminase and deamidated gliadin peptide antibodies seems to be a very useful tool for celiac disease diagnosis. Moreover, antibodies to deamidated gliadin peptides can be helpful in disease follow-up.

Hepatitis C and autoreactivity.

After the discovery of HCV in 1989 a great amount of data has been produced in order to identify a possible aetiology for a number of idiopathic diseases, especially those with a suspected immune origin. Many associations have not been confirmed by prospective studies (as in the case of autoimmune hepatitis); other immune abnormalities, such as the emergence of non organ-specific autoantibodies and cryoglobulins, have been reported by many specific studies. To date, the link between HCV and autoreactivity is tentatively explained on the basis of sequence homologies shared by the HCV polyprotein and "self" proteins (such as CYP 2D6, target of anti-LKM1) (molecular mimicry mechanism); a second interpretation relies on the demonstration that the HCV - B lymphocyte interaction is able to induce a polyclonal B cell activation, an important cofactor for the development of clinically relevant B-lymphocyte autoimmune disorders. In this review we will focus on the major aspects of the autoimmune phenomena in HCV-infected patients, their clinical and therapeutical implications.

Etanercept and infliximab induce the same serological autoimmune modifications in patients with rheumatoid arthritis.

Etanercept and infliximab treatments are often associated with autoantibodies induction. Their reported prevalences vary among different studies and the conclusions are somehow conflicting, mainly regarding whether the two drugs induce the same modifications. In this small prospective study, specifically designed to identify transient phenomena, we assess the prevalence of different relevant rheumatologic autoantibodies during anti-TNF-alpha courses in patients with rheumatoid arthritis. We report that both etanercept and infliximab transiently induce anti-DNA antibodies in 50-78% of patients, respectively, and these antibodies seem to be different from the typical lupus associated ones. Antinuclear antibodies (ANA) increased their titres and were newly produced up to 100% of patients. No other relevant antibodies are affected. Finally, as also confirmed for the first time by the patients switched from one drug to the other, the two TNF-alpha blockers behave similarly.

Evidence of a genetic basis for the different geographic occurrences of liver/kidney microsomal antibody type 1 in hepatitis C.

Antibodies to liver/kidney microsome type 1 occur in Italian patients with hepatitis C, but rarely develop in North American patients. Our goals were to compare the frequencies of the HLA markers associated with autoimmune expression in Italian and North American patients with chronic hepatitis C and to determine genetic bases for regional differences in antibody production. HLA B8, DR3, DR4, DR7, DR11, DR13, DQ2, and the B8-DR3-DQ2 haplotype were determined by microlymphocytotoxicity and polymerase chain reaction in 105 Italian patients (50 with microsomal antibodies), 100 North American patients (none with microsomal antibodies), and Italian and North American healthy control subjects. Italian patients with microsomal antibodies differed from North American patients without these antibodies by having a higher frequency of HLA DR7 (54% vs. 27%, P=0.002). HLA DR7 occurred more frequently in seropositive Italian patients than in seronegative counterparts (54% vs. 11% P < 0.0001), Italian healthy control subjects (54% vs. 29%, P=0.0009), and North American healthy control subjects (54% vs. 19%, P < 0.0001). The frequency of HLA DR7 was similar in North American patients and controls (27% vs. 19%, P=0.2), but it was lower than in Italian controls (19% vs. 29%, P=0.059). Seropositive Italian patients had a lower frequency of HLA DR11 than seronegative Italian patients and Italian controls (18% vs. 34%, P=0.07, and 18% vs. 35%, P=0.02, respectively). In contrast to seropositive Italian patients, North American patients had HLA DR4 (30% vs. 12%, P=0.02), HLA DR13 (29% vs. 10%, P=0.01), and the B8-DR3-DQ2 haplotype (23% vs. 6%, P=0.01) more often. Similarly, HLA DR4 and the B8-DR3-DQ2 phenotype were more frequent in North American patients than in Italian controls (30% vs. 16%, P=0.005, and 23% vs. 7%, P=0.00002, respectively). HLA DR7 is associated with the development of microsomal antibodies in Italian patients with chronic hepatitis C. The lower frequency of HLA DR7 in North America could contribute to the rarity of these antibodies in this region. HLA DR11 may be protective against the development of microsomal antibodies in Italian patients, whereas HLA DR4, HLA DR13, and the B8-DR3-DQ2 haplotype may be protective in North American patients.

Detection of HCV antigens in liver graft: relevance to the management of recurrent post-liver transplant hepatitis C.

The aim of this study was to evaluate how the immunohistochemical detection of liver hepatitis C virus (HCV) antigens (HCV-Ag) could support the histologic diagnosis and influence the clinical management of post-liver transplantation (LT) liver disease. A total of 215 liver specimens from 152 HCV-positive patients with post-LT liver disease were studied. Histologic coding was: hepatitis (126), rejection (34), undefined (24; coexisting rejection grade I and hepatitis), or other (31). The percentage of HCV-Ag infected hepatocytes were evaluated, on frozen sections, by an immunoperoxidase technique. HCV-Ag were detectable early in 57% of cases within 30 days post-LT, 92% of cases between 31 and 180 days, and 74% of cases after more than 180 days. Overall, HCV-Ag were detected more frequently in histologic hepatitis as compared to rejection (P < 0.0001) with a higher percentage of positive hepatocytes (P < 0.00001). In 16 patients with a high number of HCV-Ag-positive hepatocytes (65%; range 40-90%) a clinical diagnosis of recurrent hepatitis (RHC) was made despite inconclusive histopathologic diagnosis. Multivariate analysis identified the percentage of HCV-Ag-positive hepatocytes and the time post-LT as independent predictors for RHC (P = 0.008 and P = 0.041, respectively) and the number of HCV-Ag-positive hepatocytes >/=50% as the only independent predictor for nonresponse (P < 0.001) in 26 patients treated with alpha-interferon plus ribavirin. In conclusion, HCV reinfection occurs early post-LT, reaching its peak within 6 months. Immunohistochemical detection of post-LT HCV reinfection support the diagnosis of hepatitis when the histologic features are not conclusive. A high number of infected cells, independently from the genotype, represents a negative predictive factor of response to antiviral treatment.

Immunoglobulin GM and KM allotypes and prevalence of anti-LKM1 autoantibodies in patients with hepatitis C virus infection.

GM and KM allotypes-genetic markers of immunoglobulin (Ig) gamma and kappa chains, respectively-are associated with humoral immunity to several infection- and autoimmunity-related epitopes. We hypothesized that GM and KM allotypes contribute to the generation of autoantibodies to liver/kidney microsomal antigen 1 (LKM1) in hepatitis C virus (HCV)-infected persons. To test this hypothesis, we characterized 129 persons with persistent HCV infection for several GM and KM markers and for anti-LKM1 antibodies. The heterozygous GM 1,3,17 23 5,13,21 phenotype was significantly associated with the prevalence of anti-LKM1 antibodies (odds ratio, 5.13; P=0.002), suggesting its involvement in this autoimmune phenomenon in HCV infection.