Non-autoimmune Liver Diseases Research Articles

Gut microbiota in autoimmune and non-autoimmune liver diseases in children

Relevance. The influence of the gut microbiota on the development of various diseases is of great interest to researchers. The conducted studies showed that in patients with chronic liver diseases, the dominant taxa of the gut microbiota were Bifidobacterium longum, Bifidobacterium adolescentis, Blautia massiliensis, and in healthy children - Neisseria flavescens. There is no comparative analysis of data on the taxonomic diversity of the intestinal microbiota in autoimmune and non-autoimmune liver diseases in children. Purpose of the study. To investigate differences in the taxonomic diversity of fecal microbiota in patients with autoimmune and non-autoimmune liver diseases, as well as to evaluate potential biomarkers of 16S rRNA gene amplicons in these diseases by comparing the taxonomic composition. Scope and methods of research. A metagenomic analysis of the intestinal microbiota of 24 children with chronic liver diseases (mean age 10.3±4.7 years) was carried out with the identification of the V3-V4 region of the 16S rRNA gene. The group included 18 children with autoimmune liver diseases and 6 children with non-autoimmune liver diseases. Research results. The conducted study revealed 684 types of microorganisms in the studied samples of patients’ faeces. The analysis of the conducted studies showed that no dominant taxa were found in the faecal samples of children with autoimmune liver diseases, while Veillonella dispar, Veillonella parvula, Cloacibacillus porcorum, Prevotella histicola and Bacteroides eggerthii were the dominant taxa in patients with non-autoimmune liver diseases. Conclusion. Studies have shown differences in the composition of the gut microbiota in children with autoimmune and non-autoimmune liver diseases.

Comparative assessment of intestinal microbiota in autoimmune and non-autoimmune liver diseases in children

The influence of the gut microbiota on the development of various diseases is of great interest to researchers. The conducted studies showed that in patients with chronic liver diseases, the dominant taxa of the gut microbiota were Bifidobacterium longum, Bifidobacterium adolescentis, Blautia massiliensis, and in healthy children — Neisseria flavescens. There is no comparative analysis of data on the taxonomic diversity of the intestinal microbiota in autoimmune and non-autoimmune liver diseases in children. Purpose. To investigate differences in the taxonomic diversity of fecal microbiota in patients with autoimmune and non-autoimmune liver diseases, as well as to evaluate potential biomarkers of 16S rRNA gene amplicons in these diseases by comparing the taxonomic composition. Material and methods. A metagenomic analysis of the intestinal microbiota of 24 children with chronic liver diseases (mean age 10,3 ± 4,7 years) was carried out with the isolation of the 16S rRNA gene region. The group included 18 children with autoimmune liver diseases and 6 children with non-autoimmune liver diseases. Results. The conducted study revealed 684 types of microorganisms in the studied samples of patients’ feces. The analysis of the conducted studies showed that no dominant taxa were found in the fecal samples of children with autoimmune liver diseases, while Veillonella dispar, Veillonella parvula, Cloacibacillus porcorum, Prevotella histicola and Bacteroides eggerthii were the dominant taxa in patients with non-autoimmune liver diseases. Conclusion. Studies have shown differences in the composition of the gut microbiota in children with autoimmune and non-autoimmune liver diseases.

Autoantibodies to beta tubulin in autoimmune liver diseases-Relation to pANCA and clinical relevance.

There was evidence that perinuclear antineutrophil cytoplasmic antibodies (pANCA) in autoimmune liver diseases react with human beta-tubulin-5 (TBB5). Here, we reevaluate the specificity and clinical relevance of anti-TBB5 antibodies. Patients with untreated autoimmune hepatitis (AIH; n = 53), AIH under immunosuppressive therapy (AIH-IS; n = 125), primary sclerosing cholangitis (PSC; n = 40), primary biliary cholangitis (PBC; n = 250), nonautoimmune liver diseases (n = 158), inflammatory bowel diseases (IBD; n = 30), and healthy individuals (n = 62) were tested by enzyme-linked immunosorbent assay for IgG- and IgA-antibodies against recombinant human TBB5. pANCA were detected by immunofluorescence test. Sera were absorbed with TBB5 coupled to cyanogen bromide-activated sepharose. Prevalence and reactivity of IgG anti-TBB5 were significantly higher in patients with untreated AIH (68%; arbitrary units [AU] median: 369) than in PSC (28%; AU median: 84, P < 0.001), other liver diseases (14%; AU median: 185, P < 0.0001), IBD (3%; AU median: 111, P < 0.0001), and healthy controls (3%; AU median: 135; P < 0.0001). Anti-TBB5 did not correlate with pANCA, and immunoprecipitation with TBB5 did not abolish pANCA reactivity. In untreated AIH, anti-TBB5-reactivity was significantly higher than in AIH-IS. Transaminases decreased under IS preferentially in anti-TBB5-negative patients. There was no correlation between anti-TBB5-reactivity and histological stages. IgA-anti-TBB5 was mainly found in alcohol-associated liver disease (ALD; 39%). Our data do not support TBB5 as an autoantigenic target of pANCA. However, IgG-anti-TBB5 showed high specificity for (untreated) AIH. While they did not correlate with histological and laboratory parameters, their presence may indicate a poor response to IS.

Features of the gut microbiota in children with chronic liver diseases

The value of the liver–gut axis is increasingly recognized as a major modulator of autoimmunity. There is no comparative analysis of data on the taxonomic diversity of the intestinal microbiota in chronic liver diseases in children. Purpose. To investigate the taxonomic diversity of the intestinal microbiota in children with chronic liver diseases compared with healthy patients, to identify differences in bacterial diversity in autoimmune and non-autoimmune liver diseases, as well as the impact of immunosuppressive therapy on the intestinal microbiota. Material and methods. A metagenomic analysis of the gut microbiota of 24 children with chronic liver diseases (mean age 10,3 ± 4,7 years) was carried out with the identification of the V3–V4 region of the 16S rRNA gene. The group included 18 children with autoimmune liver diseases and 6 children with non-autoimmune liver diseases. The control group consisted of fecal samples of 34 apparently healthy children. Results. When comparing fecal samples of children with autoimmune liver diseases with samples of healthy children, the taxa of Bacteroides dorei, Collinsella aerofaciens, Ruminococcus caffidurs prevailed, and for children of the control group — Neisseria flavescens. When comparing samples of patients with non-autoimmune liver diseases and the control group, it was found that the taxa Bacteroides fragilis, Klebsiella pneumoniae, Bifidobacterium longum prevailed in healthy children. When comparing fecal samples from children with autoimmune and non-autoimmune liver diseases, it was found that Veillonella dispar, Cloacibacillus porcorum, Veillonella parvula, Prevotella histicola and Bacteroides eggerthii taxa dominate in patients with non-autoimmune diseases. No dominant taxa of the gut microbiota were found in children with autoimmune liver diseases. It has been established that the taxa Veillonella dispar, Faecalibacterium prausnitzii, Roseburia inulinivorans, Bacteroides xylanisolvens and Alistipes obesi prevail in patients receiving immunosuppressive therapy, and the taxa Phascolarctobacterium succinatutens, Bacteroides ovatus, Solobacterium mooreis and Holdemanella massilien prevail in patients not receiving immunosuppressive therapy. Conclusion. A recent study of the gut microbiota in children with chronic liver disease shows differences in the imbalance of the gut microbiota compared to the results obtained in adults. The gut microbiota model is capable of distinguishing autoimmune liver diseases from non-autoimmune diseases. Immunosuppressive therapy is accompanied by the dominance of taxa that reduce the production of short-chain fatty acids.

Effect of ursodeoxycholic acid on the intestinal microbiota in children with chronic liver disease

Ursodeoxycholic acid is a secondary bile acid (BA), present in humans at low concentrations, with well-known therapeutic properties, and was originally used to treat cholestatic liver disease. However, there are very few studies on the effect of ursodeoxycholic acid on the composition of the gut microbiota, especially in children with chronic liver diseases.Purpose. To determine differences in the taxonomic diversity of the fecal microbiota in children with chronic liver disease who receive or do not receive ursodeoxycholic acid.Material and methods. A metagenomic analysis of the intestinal microbiota of 24 children with chronic liver diseases (mean age 10.3 ± 4.7 years) was carried out with the identification of the V3–V4 region of the 16S rRNA gene. The group included 18 children with autoimmune liver diseases and 6 children with non-autoimmune liver diseases. 17 children received ursodeoxycholic acid. The comparison group consisted of 7 children who did not receive ursodeoxycholic acid.Results. This study found that fecal samples from patients treated with ursodeoxycholic acid do not differ in the taxonomic diversity of the gut microbiota from samples from patients not treated with ursodeoxycholic acid. A more detailed study to determine the existing taxonomic diversity in samples of patients treated with ursodeoxycholic acid and not treated with ursodeoxycholic acid, using the sPLS-DA method, showed that taxa such as Streptococcus anginosus, Coprococcus eutactus, Desulfovibrio desulfuricans, Angelakisella massiliensis and Gemella haemolysans dominated in patients not treated with ursodeoxycholic acid. And for patients receiving drugs with ursodeoxycholic acid, the dominance of the taxon Anaerostipes hadrus is typical. An analysis of differences in the percentage of intestinal microbiota bacterial species showed that patients receiving ursodeoxycholic acid had a higher count of Anaerostipes hadrus, while in patients not receiving ursodeoxycholic acid preparations, the count of Bacteroides dorei, Akkermansia muciniphila was significantly increased, and the counts of other bacteria were also increased.Conclusion. Studies have shown that ursodeoxycholic acid has a positive effect on the intestinal microbiota in children with chronic liver disease by increasing the number of microorganisms that produce short-chain fatty acids.

Gut microbiota in chronic liver diseases in children

The impact of gut microbiota on the development of various diseases is of great interest to researchers. However, data on the taxonomic diversity of the intestinal microbiota in chronic liver diseases in children are lacking.Purpose. To study the taxonomic diversity of the fecal microbiota in children with chronic liver diseases in comparison with healthy patients.Material and methods. A metagenomic analysis of the intestinal microbiota of 24 children with chronic liver diseases (mean age 10.3 ± 4.7 years) was carried out with the isolation of the target fragment of the 16S rRNA gene. The group included 18 children with autoimmune liver diseases and 6 children with non-autoimmune liver diseases. The comparison group consisted of fecal samples of 34 apparently healthy children.Results. The conducted study revealed 684 types of microorganisms in the studied samples of patients’ feces. An analysis of the conducted studies showed that fecal samples of healthy children and patients with chronic liver diseases differ in bacterial diversity. The dominant taxa in healthy children were Neisseria flavescens, in patients with chronic liver diseases, the dominant taxa were Bifidobacterium longum, Bifidobacterium adolescentis, Blautia massiliensis. At the same time, Bifidobacterium longum, Bifidobacterium adolescentis, Blautia massiliensis in fecal samples of patients with chronic liver diseases was 8 times as high.Conclusion. Studies have shown differences in the composition of the intestinal microbiota in healthy children and children with chronic liver diseases.

Epigenetic Aspects and Prospects in Autoimmune Hepatitis.

The observed risk of autoimmune hepatitis exceeds its genetic risk, and epigenetic factors that alter gene expression without changing nucleotide sequence may help explain the disparity. Key objectives of this review are to describe the epigenetic modifications that affect gene expression, discuss how they can affect autoimmune hepatitis, and indicate prospects for improved management. Multiple hypo-methylated genes have been described in the CD4+ and CD19+ T lymphocytes of patients with autoimmune hepatitis, and the circulating micro-ribonucleic acids, miR-21 and miR-122, have correlated with laboratory and histological features of liver inflammation. Both epigenetic agents have also correlated inversely with the stage of liver fibrosis. The reduced hepatic concentration of miR-122 in cirrhosis suggests that its deficiency may de-repress the pro-fibrotic prolyl-4-hydroxylase subunit alpha-1 gene. Conversely, miR-155 is over-expressed in the liver tissue of patients with autoimmune hepatitis, and it may signify active immune-mediated liver injury. Different epigenetic findings have been described in diverse autoimmune and non-autoimmune liver diseases, and these changes may have disease-specificity. They may also be responses to environmental cues or heritable adaptations that distinguish the diseases. Advances in epigenetic editing and methods for blocking micro-ribonucleic acids have improved opportunities to prove causality and develop site-specific, therapeutic interventions. In conclusion, the role of epigenetics in affecting the risk, clinical phenotype, and outcome of autoimmune hepatitis is under-evaluated. Full definition of the epigenome of autoimmune hepatitis promises to enhance understanding of pathogenic mechanisms and satisfy the unmet clinical need to improve therapy for refractory disease.

Constitutive Activation of Natural Killer Cells in Primary Biliary Cholangitis.

Natural killer (NK) cells are innate immune cells that interface with the adaptive immune system to generate a pro-inflammatory immune environment. Primary Biliary Cholangitis (PBC) is a hepatic autoimmune disorder with extrahepatic associations including systemic sclerosis, Sjogren's syndrome and thyroiditis. Immunogenetic studies have identified polymorphisms of the IL-12/STAT4 pathway as being associated with PBC. As this pathway is important for NK cell function we investigated NK cells in PBC. Circulating NK cells from individuals with PBC were constitutively activated, with higher levels of CD49a and the liver-homing marker, CXCR6, compared to participants with non-autoimmune chronic liver disease and healthy controls. Stimulation with minimal amounts of IL-12 (0.005 ng/ml) led to significant upregulation of CXCR6 (p < 0.005), and enhanced IFNγ production (p < 0.02) on NK cells from PBC patients compared to individuals with non-autoimmune chronic liver disease, indicating dysregulation of the IL-12/STAT4 axis. In RNAseq studies, resting NK cells from PBC patients had a constitutively activated transcriptional profile and upregulation of genes associated with IL-12/STAT4 signaling and metabolic reprogramming. Consistent with these findings, resting NK cells from PBC patients expressed higher levels of pSTAT4 compared to control groups (p < 0.001 vs. healthy controls and p < 0.05 vs. liver disease controls). In conclusion NK cells in PBC are sensitive to minute quantities of IL-12 and have a “primed” phenotype. We therefore propose that peripheral priming of NK cells to express tissue-homing markers may contribute to the pathophysiology of PBC.

High Frequency of Concomitant Food Allergy Development and Autoantibody Formation in Children Who Have Undergone Liver Transplantation.

Allergy and other immune-mediated diseases are more frequently reported in children who have undergone liver transplantation. Furthermore, autoantibodies are also prevalent, suggesting a state of immune dysregulation in these patients. Whether or not these processes occur simultaneously in the same individual has not been studied previously. A cohort of 43 children who had undergone liver transplantation for nonautoimmune liver disease at median age of 1.3 years was investigated for allergy and autoimmune disease. Sensitization to food and inhalant allergens was assessed, and autoantibodies were measured. The prevalence of food allergy was 26% and that of respiratory allergy was 23%, whereas 33% and 26% of the subjects were sensitized to food and inhalant allergens, respectively. Autoimmune disease (ie, autoimmune hepatitis) occurred in a single individual (2%), whereas autoantibodies were present in 44% of the children. Food allergy and autoantibodies occurred concomitantly in 19% of the children, which was almost twice the frequency expected by chance (11%, P = 0.04). Respiratory allergy and the presence of autoantibodies were unrelated (12% concurrence versus the expected 10%, P = 0.73). In the logistic regression analysis, autoantibody formation was associated with discontinued immunosuppression and food allergy, with odds ratios of 13 (P = 0.01) and 7.1 (P = 0.03), respectively. In contrast to respiratory allergy, food allergy and autoantibody formation occurred together in the same children who underwent liver transplantation at a frequency higher than would be expected by chance. This may reflect an underlying immune dysregulation that impairs immune tolerance to both food allergens and autoantigens.

De novo autoimmune hepatitis after liver transplantation: A focus on glutathione S-transferase theta 1.

De novo autoimmune hepatitis (DAIH) is a rare clinical condition with features that resemble those of autoimmune hepatitis (AIH) in patients undergoing liver transplantation (LT) for nonautoimmune liver disease. The diagnosis of this entity has been based on the presence of biochemical and histological patterns similar to those observed in the primary AIH, although several considerations must be taken into account. The impact of DAIH on graft survival is relevant, and early diagnosis and treatment is associated with a good longterm outcome. Although glutathione S-transferase theta 1 (GSTT1) alloimmune recognition has been shown to be involved in the pathogenesis of DAIH, further studies are necessary to fully determine its pathogenic mechanisms and risk factors. We review the pathophysiology, the most common histological patterns, the treatment strategies, and the longterm outcomes of DAIH after LT with a special focus on GSTT1. Liver Transplantation 23:75-85 2017 AASLD.

Recurrence of autoimmune liver disease and inflammatory bowel disease after pediatric liver transplantation

Approximately 10% of children with autoimmune hepatitis (AIH) and 30% of those with sclerosing cholangitis (SC) require liver transplantation (LT). LT is indicated in patients who present with fulminant hepatic failure (ie, with encephalopathy) and in those who develop end-stage liver disease despite treatment. After LT, recurrent AIH is reported in approximately 30% of patients and recurrent SC in up to 50%. Diagnosis of recurrence is based on biochemical abnormalities, seropositivity for autoantibodies, interface hepatitis on histology, steroid dependence, and, for SC, presence of cholangiopathy. Recurrence of SC after LT is often associated with poorly controlled inflammatory bowel disease (IBD). Recurrence may even appear years after LT; therefore, steroid-based immunosuppression should be maintained at a higher dose than that used for patients transplanted for nonautoimmune liver diseases. Although the impact of recurrent disease on graft function is controversial, it seems that in pediatric LT recipients recurrence of AIH or SC is associated with compromised graft survival. Exacerbation of preexistent IBD may be observed after LT for SC or AIH, and IBD appears to have a more aggressive course than before LT. In addition, IBD can develop de novo following LT. Liver Transplantation 22 1275-1283 2016 AASLD.

Factors that Influence Health-Related Quality of Life in Patients with Primary Sclerosing Cholangitis.

Primary sclerosing cholangitis (PSC) is an incurable, cholestatic liver disease often coincident with inflammatory bowel disease (IBD). To evaluate the impact of liver disease and IBD on health-related quality of life (HRQoL) in PSC. A mixed-methods, cross-sectional study was performed at a tertiary center. Short Form-36 (SF-36) scores were compared between PSC, Canadian normative data, and disease controls. Disease-specific instruments scores [PBC-40, Short IBD questionnaire, Liver Disease Quality of Life Questionnaire (LDQOL)] were compared between PSC and disease controls. Multivariable regression identified factors independently associated with final SF-36 component scores. Qualitative evaluation of patient questionnaires was performed using a content analysis framework. One hundred and sixty-two surveys were completed (99 PSC, 26 primary biliary cirrhosis, 16 non-autoimmune cholestatic liver disease, and 21 IBD). PSC patients had significantly lower SF-36 scores than Canadian controls, but similar scores to disease controls. LDQOL most accurately predicted HRQoL. Factors negatively associated with physical HRQoL included shorter IBD duration, liver disease symptoms, and decompensated cirrhosis. Mental HRQoL was influenced by liver disease and IBD symptoms, pruritus, social isolation, and depression. Nearly 75% expressed existential anxiety regarding disease progression and diminished life expectancy, with 25% disclosing social isolation. Patients with PSC have significantly lower HRQoL than healthy controls. Both symptoms of IBD and chronic liver disease impact HRQoL in patients with PSC, which lead to significant psychologic burden that is expressed by existential anxieties and social isolation. A PSC-specific HRQoL tool is critical to adequately quantify the distinct impact of IBD and cholestatic liver disease.

Treatment of cholestatic fibrosis by altering gene expression of Cthrc1: Implications for autoimmune and non-autoimmune liver disease

Collagen triple helix repeat containing-1 (Cthrc1) is a documented specific inhibitor of TGF-β signaling. Based on this observation, we developed the hypothesis that knocking in/knocking out the Cthrc1 gene in murine models of cholestasis would alter the natural history of cholestatic fibrosis. To study this thesis, we studied two murine models of fibrosis, first, common bile duct ligation (CBDL) and second, feeding of 3, 5-diethoxy-carbonyl-1, 4-dihydrocollidine (DDC). In both models, we administered well-defined adenoviral vectors that expressed either Cthrc1 or, alternatively, a short hairpin RNA (shRNA)-targeting Cthrc1 either before or after establishment of fibrosis. Importantly, when Cthrc1 gene expression was enhanced, we noted a significant improvement of hepatic fibrosis, both microscopically and by analysis of fibrotic gene expression. In contrast, when Cthrc1 gene expression was deleted, there was a significant exacerbation of fibrosis. To identify the mechanism of action of these significant effects produced by knocking in/knocking out Cthrc gene expression, we thence studied the interaction of Cthrc1 gene expression using hepatic stellate cells (HSCs) and human LX-2 cells. Importantly, we demonstrate that Cthrc1 is induced by TGF-β1 via phospho-Smad3 binding to the promoter with subsequent transcription activation. In addition, we demonstrate that Cthrc1 inhibits TGF-β signaling by accelerating degradation of phospho-Smad3 through a proteosomal pathway. Importantly, the anti-fibrotic effects can be recapitulated with a truncated fragment of Cthrc1. In conclusion, our findings uncover a critical negative feedback regulatory loop in which TGF-β1 induces Cthrc1, which can attenuate fibrosis by accelerating degradation of phospho-Smad3.

Autoantibody profiling of patients with primary biliary cirrhosis using a multiplexed line-blot assay

ObjectiveTo evaluate the autoantibody profile in patients with primary biliary cirrhosis (PBC) using a new multiplexed line-blot assay specifically designed for the diagnosis of autoimmune liver diseases. MethodsSera of 58 consecutive PBC patients and 191 disease controls (144 with autoimmune liver diseases other than PBC, and 67 with non-autoimmune chronic liver diseases) were tested by both the multiplexed line-blot Autoimmune Liver Disease Profile 2 (ALD2) and by IIF on HEp-2 cells and on rat kidney/liver/stomach tissues. ALD2 contains the following PBC-associated antigens: AMA-M2, natively purified from bovine heart; M2-E3, a recombinant fusion protein including the E2 subunits of PDC, BCOADC and OGDC; sp100, PML and gp210 recombinant proteins. ResultsWith the ALD2 assay, a positive reaction to AMA-M2, M2-E3, sp100, PML and gp210 in PBC patients was observed in 77.6%, 84.5%, 34.5%, 15.1% and 18.9%, respectively, of the PBC sera. The overall sensitivity and specificity for PBC were 98.3% and 93.7%. Using IIF, positivity rates to AMA, and to antinuclear autoantibodies with membranous/rim-like and multiple nuclear dot patterns were 86.2%, 8.6% and 22.4%, respectively. The overall sensitivity and specificity for PBC of the IIF method were 86.2% and 97.9%, respectively. ConclusionsThe ALD2 line-blot showed a good diagnostic accuracy for PBC and a higher sensitivity than the IIF method to detect sp100 and gp210 autoantibodies.

Factors Affecting Health-Related Quality of Life and Physical Activity after Liver Transplantation for Autoimmune and Nonautoimmune Liver Diseases: A Prospective, Single Centre Study

Background/Aim. With the improvement of the outcomes after liver transplantation (LTx), health-related quality of life (HRQoL) and physical activity are becoming significant outcome parameters. We prospectively assessed these parameters in patients with autoimmune and nonautoimmune liver disorders undergoing LTx. Materials and Methods. Patients (n = 107) were subdivided into 3 groups depending on the time after LTx: group-A (n = 21): 6–12 months; group-B (n = 48): 13–36 months; and group-C (n = 38): >37 months. SF-36 and IPAQ were applied in HRQoL and physical activity assessment. Results. Females had impaired HRQoL in most SF-36 domains. Younger patients showed higher scores at SF-36 physical functioning domain but IPAQ was not influenced by age. Group-B had higher general health and physical component summary than group-A (P = 0.037, P = 0.04, resp.) and total IPAQ than group-C (P = 0.047). The sitting time domain was longer in group-A than in group-B and group-C (P = 0.0157; P = 0.042, resp.). Employed patients had better HRQoL and higher physical activity than those not working. SF-36 and IPAQ were unrelated to the autoimmune etiology of liver disease. Conclusions. These findings show that female and unemployed patients have worse HRQoL, while gender and age at LTx time do not affect IPAQ's physical activity. The autoimmune etiology of liver disease does not influence HRQoL and physical activity after LTx.

HLA variants related to primary sclerosing cholangitis influence rejection after liver transplantation.

To investigate influence of human leukocyte antigen (HLA) and killer immunoglobuline-like receptor (KIR) genotypes on risks of acute rejection (AR) after liver transplantation (LTX). In this retrospective study we included 143 adult donor-recipient pairs with a minimum of 6 mo follow-up after LTX for whom DNA was available from both donor and recipients. Clinical data, all early complications including episodes and severity of AR and graft/patient survival were registered. The diagnosis of AR was based on clinical, biochemical and histological criteria. All suspected episodes of AR were biopsy confirmed. Key classical HLA loci (HLA-A, HLA-B, HLA-C and HLA-DRB1) were genotyped using Sanger sequencing. 16 KIR genes were genotyped using a novel real time PCR approach which allows for determination of the diploid copy number of each KIR gene. Immunohistochemical staining for T (CD3), B (CD20) and natural killer (NK) cells (CD56 and CD57) were performed on liver biopsies from 3 different patient groups [primary sclerosing cholangitis (PSC), primary biliary cirrhosis and non-autoimmune liver disease], 10 in each group, with similar grade of AR. Fourty-four (31%) patients were transplanted on the basis of PSC, 40% of them had AR vs 24% in the non-PSC group (P = 0.04). No significant impact of donor-recipient matching for HLA and KIR genotypes was detected. In the overall recipient population an increased risk of AR was detected for HLA-B*08 (P = 0.002, OR = 2.5; 95%CI: 1.4-4.6), HLA-C*07 (P = 0.001, OR = 2.4; 95%CI: 1.4-4.0) and HLA-DRB1*03 (P = 0.03, OR = 1.9; 95%CI: 1.0-3.3) and a decreased risk for HLA-DRB1*04 (P = 0.001, OR = 0.2; 95%CI: 0.1-0.5). For HLA-B*08, HLA-C*07 and DRB1*04 the associations remained evident in a subgroup analysis of non-PSC recipients (P = 0.04, P = 0.003 and P = 0.02, respectively). In PSC recipients corresponding P values were 0.002, 0.17 and 0.01 for HLA-B*08, HLA-C*07 and DRB1*04, respectively. A dosage effect of AR prevalence according to the PSC associated HLA alleles was also notable in the total recipient population. For HLA-B*08 the frequency of AR was 56% in HLA-B*08 homozygous recipients, 39% in heterozygous recipients and 21% in recipients lacking HLA-B*08 (P = 0.02). The same was observed for the HLA-C*07 allele with AR in 57%, 27% and 18% in recipients being homozygous, heterozygous and lacking HLA-C*07 respectively (P = 0.003). Immunohistochemical analysis showed similar infiltration of T, B and NK cells in biopsies with AR in all three groups. We found significant associations between the PSC-associated HLA-B*08, HLA-C*07, HLA-DRB1*03 and HLA-DRB1*04 alleles and risk of AR in liver transplant recipients.

Presence of antibodies against self human leukocyte antigen class II molecules in autoimmune hepatitis.

Autoimmune hepatitis (AIH) can arise de novo after liver transplantation (LT) for non-autoimmune liver diseases. Considering the identical features of de novo AIH after LT and classical AIH, as well as the importance of anti-human leukocyte antigen (HLA) antibodies in graft rejection, we investigated the presence of circulating anti-HLA class II antibodies in the sera of 35 patients with AIH, 30 patients with primary biliary cirrhosis (PBC), and 30 healthy donors using fluorescent dye-impregnated beads bound to HLA molecules. We then investigated the allele specificity of the antibodies and identified the HLA alleles in each patient using DNA-based HLA typing. We also examined HLA class II expression in liver samples using immunohistochemistry. Anti-HLA class II antibodies were detected significantly more frequently in the patients with AIH (88.1%) than in the patients with PBC (33.3%) or in the healthy donors (13.3%) (both P <0.01). We confirmed that the anti-HLA class II antibodies in the AIH patients showed specificity for several HLA class II alleles, including self HLA class II alleles. Moreover, positive reactivity with anti-self HLA class II antibodies was associated with higher serum transaminase levels. In conclusion, we demonstrated, for the first time, that antibodies against self HLA class II alleles were detectable in patients with AIH. Our results suggest that an antibody-mediated immune response against HLA class II molecules on hepatocytes may be involved in the pathogenesis or acceleration of liver injury in AIH.

Challenge of liver disease in systemic lupus erythematosus: Clues for diagnosis and hints for pathogenesis.

Systemic lupus erythematosus (SLE) encompass a broad spectrum of liver diseases. We propose here to classify them as follows: (1) immunological comorbilities (overlap syndromes); (2) non-immunological comorbilities associated to SLE; and (3) a putative liver damage induced by SLE itself, referred to as "lupus hepatitis". In the first group, liver injury can be ascribed to overlapping hepatopathies triggered by autoimmune mechanisms other than SLE occurring with higher incidence in the context of lupus (e.g., autoimmune hepatitis, primary biliary cirrhosis). The second group includes non-autoimmune liver diseases, such as esteatosis, hepatitis C, hypercoagulation state-related liver lesions, hyperplasic parenchymal and vascular lesions, porphyria cutanea tarda, and drug-induced hepatotoxicity. Finally, the data in the literature to support the existence of a hepatic disease produced by SLE itself, or the occurrence of a SLE-associated prone condition that increases susceptibility to acquire other liver diseases, is critically discussed. The pathological mechanisms underlying each of these liver disorders are also reviewed. Despite the high heterogeneity in the literature regarding the prevalence of SLE-associated liver diseases and, in most cases, lack of histopathological evidence or clinical studies large enough to support their existence, it is becoming increasingly apparent that liver is an important target of SLE. Consequently, biochemical liver tests should be routinely carried out in SLE patients to discard liver disorders, particularly in those patients chronically exposed to potentially hepatotoxic drugs. Diagnosing liver disease in SLE patients is always challenging, and the systematization of the current information carried out in this review is expected to be of help both to attain a better understanding of pathogenesis and to build an appropriate work-up for diagnosis.

Significance of histopathological features in differentiating autoimmune liver disease from nonautoimmune chronic liver disease in children

Autoimmune liver disease (AILD) requires a constellation of clinical, serological, biochemical, and histological findings for diagnosis. Liver biopsy forms the cornerstone for the definite diagnosis of AILD, despite histological features not being pathognomonic. Liver biopsies of AILD and nonautoimmune chronic liver disease (NACLD) were reviewed blindly to assess the role of typical histological findings in differentiating AILD from NACLD in a pediatric population. Twenty-five liver biopsies of AILD and 34 liver biopsies of NACLD were reviewed retrospectively without knowledge of the final diagnosis. The typical histology comprising all four features, interface hepatitis, portal lymphoplasmacytic infiltrate, rosette formation, and emperipolesis, was observed in 56% of AILD. Rosette formation and emperipolesis were associated significantly with the diagnosis of AILD. Rosette formation alone or in combination with emperipolesis or lymphoplasmacytic infiltrate had high specificity (96.2% each) but low sensitivity (68, 60, and 60%, respectively) for AILD. The diagnostic accuracy of typical histology comprising of a combination of at least three of four features, rosette formation, emperipolesis, and lymphoplasmacytic infiltrate, was 76.9%, with a positive predictive value of 93.3% and a negative predictive value of 70.2%. Characteristic patterns of liver injury comprising typical histological features on liver biopsy may strongly suggest the diagnosis of AILD irrespective of other laboratory parameters in children. Rosette formation was the only independent significant histological factor to predict AILD. High specificity and predictability of typical histological features may be helpful in diagnosing seronegative AILD among cases of cryptogenic liver disease in the absence of other supportive findings.

Development of autoantibodies after pediatric liver transplantation

Dn-AIH is a long-term complication after LT. The aim of this study was to analyze the occurrence of autoantibodies in pediatric recipients and the clinical significance. From 1992 to 2008, 96 pediatric LT for non-autoimmune liver diseases were performed in 94 children in our institution. Serum autoantibodies were checked in 68 subjects (73.9%). A positive autoantibody was defined as titers ≥1:40 for ANA, or ≥1:20 for ASMA, anti-LKM, and AMA. Autoantibodies were detectable in 51 of 68 patients (75.0%). There was positivity for ANA in 30 patients, ASMA in 32, and AMA in three, while anti-LKM was all negative. Immunosuppressive treatment with CsA, more than one episode of rejection, and abnormal ALT were risk factors for the development of autoantibodies. The incidence of the development of autoantibodies was 75.0% in pediatric LT cases in this study. ASMA was the most commonly found autoantibody. Autoantibodies may not play a sentinel role for dn-AIH after LT.