Drug-induced autoimmune hepatitis:A minireview

Drug-induced autoimmune hepatitis(DIAIH)is a specific phenotype of druginduced liver injury that may lead to the devastating outcome of acute liver failure requiring liver transplantation.Drugs implicated in DIAIH include antimicrobials such as nitrofurantoin and minocycline,non-steroidal anti-inflammatory drugs,statins as well as anti-tumor necrosis agents.The clinical features of druginduced liver injury are indistinguishable from idiopathic autoimmune hepatitis(AIH)as both may have positive AIH-related autoantibodies,elevated immunoglobulin G,as well as similar histopathological findings.In patients who show no clinical improvement,or there is progressive liver injury despite cessation of the suspected drug,a liver biopsy should be considered,whereby the presence of advance fibrosis on histology favors the diagnosis of idiopathic AIH.Empirical treatment with corticosteroids may be required in patients with non-resolving liver injury.A typical clinical scenario supportive of DIAIH includes a history of drug exposure with spontaneous resolution of liver injury after drug withdrawal and the absence of relapse after rapid steroid taper.In this article we report two cases of DIAIH secondary to Sorafenib and Atorvastatin along with a review of currently available literature.Early identification and treatment often lead to a favorable outcome in DIAIH.

CD4+Foxp3+CD25+/-Tregs characterize liver tissue specimens of patients suffering from drug-induced autoimmune hepatitis:A clinical-pathological study

Background: The diagnosis of drug-induced autoimmune hepatitis(DIAIH) and its differentiation from idiopathic autoimmune hepatitis(AIH) is challenging. This study aimed to differentiate DIAIH from AIH by comparing the biochemical changes, histological features, and frequencies of CD4~+Foxp3~+CD25+/-regulatory T cells(Tregs) in liver tissues or peripheral blood lymphocytes.Methods: A total of 15 DIAIH patients and 24 AIH patients who underwent liver biopsies at initial presentation were enrolled in this study. The liver histological changes were assessed by HE staining. The phenotypic recognition and distribution of CD4~+Foxp3~+CD25+/-Tregs in liver tissues were evaluated by single/double immunostains in serial sections. The CD4~+Foxp3~+CD25+/-Tregs in peripheral blood were analyzed by flow cytometry.Results: The median values of ALT and AST were 404.50 U/L and 454.10 U/L in DIAIH patients and309.50 U/L and 315.00 U/L in AIH patients, respectively. More importantly, for the first time we found that patients with DIAIH had higher levels of serum ALT and AST, more severe degree of lobular inflammation,higher frequencies of zone 3 necrosis and higher number of lobular CD4~+Foxp3~+CD25~-Tregs compared with AIH(P < 0.05). Furthermore, there were positive correlations in DIAIH between the degree of lobular inflammation and either the AST/ALT level or the number of lobular CD4~+Foxp3~+CD25~-Tregs(P < 0.05).However, the frequency of peripheral blood CD4~+Foxp3~+CD25+/-Tregs were not significantly different between DIAIH and AIH.Conclusions: The differences of ALT, AST and the number of lobular CD4~+Foxp3~+CD25~-Tregs between patients with DIAIH and those with AIH are clinically helpful in differentiating these two diseases in their early stage.

Autoimmune hepatitis and primary sclerosing cholangitis after direct-acting antiviral treatment for hepatitis C virus:A case report

BACKGROUND Chronic hepatitis C virus(HCV)infection is a major global health concern that leads to liver fibrosis,cirrhosis,and cancer.Regimens containing direct-acting antivirals(DAAs)have become the mainstay of HCV treatment,achieving a high sustained virological response(SVR)with minimal adverse events.CASE SUMMARY A 74-year-old woman with chronic HCV infection was treated with the DAAs ledipasvir,and sofosbuvir for 12 wk and achieved SVR.Twenty-four weeks after treatment completion,the liver enzyme and serum IgG levels increased,and antinuclear antibody became positive without HCV viremia,suggesting the development of autoimmune hepatitis(AIH).After liver biopsy indicated AIH,a definite AIH diagnosis was made and prednisolone was initiated.The treatment was effective,and the liver enzyme and serum IgG levels normalized.However,multiple strictures of the intrahepatic and extrahepatic bile ducts with dilatation of the peripheral bile ducts appeared on magnetic resonance cholangiopancreatography after 3 years of achieving SVR,which were consistent with primary sclerosing cholangitis.CONCLUSION The potential risk of developing autoimmune liver diseases after DAA treatment should be considered.

Management of autoimmune hepatitis induced by hepatitis delta virus

Approximately 12-72 million people worldwide are co-infected with hepatitis B virus(HBV)and hepatitis delta virus(HDV).This concurrent infection can lead to several severe outcomes with hepatic disease,such as cirrhosis,fulminant hepatitis,and hepatocellular carcinoma,being the most common.Over the past few decades,a correlation between viral hepatitis and autoimmune diseases has been reported.Furthermore,autoantibodies have been detected in the serum of patients co-infected with HBV/HDV,and autoimmune features have been reported.However,to date,very few cases of clinically significant autoimmune hepatitis(AIH)have been reported in patients with HDV infection,mainly in those who have received treatment with pegylated interferon.Interestingly,there are some patients with HBV infection and AIH in whom HDV infection is unearthed after receiving treatment with immunosuppressants.Consequently,several questions remain unanswered with the challenge to distinguish whether it is autoimmune or“autoimmune-like”hepatitis being the most crucial.Second,it remains uncertain whether autoimmunity is induced by HBV or delta virus.Finally,we investigated whether the cause of AIH lies in the previous treatment of HDV with pegylated interferon.These pressing issues should be elucidated to clarify whether new antiviral treatments for HDV,such as Bulevirtide or immu-nosuppressive drugs,are more appropriate for the management of patients with HDV and AIH.

Knockout of C6orf120 in Rats Alleviates Concanavalin A-induced Autoimmune Hepatitis by Regulating Macrophage Polarization

Objective The effect of the functionally unknown gene C6orf120 on autoimmune hepatitis was investigated on C6orf120 knockout rats(C6orf120^(-/-))and THP-1 cells.Method Six–eight-week-old C6orf120^(-/-)and wild-type(WT)SD rats were injected with Con A(16 mg/kg),and euthanized after 24 h.The sera,livers,and spleens were collected.THP-1 cells and the recombinant protein(rC6ORF120)were used to explore the mechanism in vitro.The frequency of M1 and M2 macrophages was analyzed using flow cytometry.Western blotting and PCR were used to detect macrophage polarization-associated factors.Results C6orf120 knockout attenuated Con A-induced autoimmune hepatitis.Flow cytometry indicated that the proportion of CD68^(+)CD86^(+)M1 macrophages from the liver and spleen in the C6orf120^(-/-)rats decreased.C6orf120 knockout induced downregulation of CD86 protein and the mRNA levels of related inflammatory factors TNF-α,IL-1β,and IL-6 in the liver.C6orf120 knockout did not affect the polarization of THP-1 cells.However,rC6ORF120 promoted the THP-1 cells toward CD68^(+)CD80^(+)M1 macrophages and inhibited the CD68^(+)CD206^(+)M2 phenotype.Conclusion C6orf120 knockout alleviates Con A-induced autoimmune hepatitis by inhibiting macrophage polarization toward M1 macrophages and reducing the expression of related inflammatory factors in C6orf120^(-/-)rats.

Autoimmune hepatitis-primary biliary cholangitis overlap syndrome complicated by various autoimmune diseases:A case report

BACKGROUND Autoimmune hepatitis(AIH)and primary biliary cholangitis(PBC)are two common clinical autoimmune liver diseases,and some patients have both diseases;this feature is called AIH-PBC overlap syndrome.Autoimmune thyroid disease(AITD)is the most frequently overlapping extrahepatic autoimmune disease.Immunoglobulin(IgG)4-related disease is an autoimmune disease recognized in recent years,characterized by elevated serum IgG4 levels and infiltration of IgG4-positive plasma cells in tissues.CASE SUMMARY A 68-year-old female patient was admitted with a history of right upper quadrant pain,anorexia,and jaundice on physical examination.Laboratory examination revealed elevated liver enzymes,multiple positive autoantibodies associated with liver and thyroid disease,and imaging and biopsy suggestive of pancreatitis,hepatitis,and PBC.A diagnosis was made of a rare and complex overlap syndrome of AIH,PBC,AITD,and IgG4-related disease.Laboratory features improved on treatment with ursodeoxycholic acid,methylprednisolone,and azathioprine.CONCLUSION This case highlights the importance of screening patients with autoimmune diseases for related conditions.

Fermented Lentinus edodes extract containingα-glucan ameliorates concanavalin A-induced autoimmune hepatitis in mice

Autoimmune hepatitis(AIH)is a chronic inflammatory liver disease that threatens human health worldwide.The aim of this study was to detect the protective effect of a fermented Lentinus edodes extract containingα-glucan(FLA),in a concanavalin A(Con A)-induced AIH mouse model and to determine the underlying liver-protective mechanism.The results showed that compared with the model group,the level of proinflammatory cytokines in serum of FLA pretreated mice was significantly decreased,and the degree of inflammatory cell infiltration in liver,thymus and spleen was significantly reduced.Quantitative polymerase chain reaction,immunohistochemistry,and Western blotting showed that FLA pre-treatment inhibited the Con A-induced apoptosis of hepatocytes by down-regulating the expression of BAX and up-regulating the expression of BCL-2.Further research found that FLA may improve liver injury in mice by activating NRF2 signaling pathway and inhibiting TRAF6/NF-κB signaling pathway.Thus,FLA may improve liver injury in mice by shifting gut microbial composition to reduce the release of inflammatory cytokines in the serum and prevent the necrosis of hepatocytes.Up-regulation of NRF2 signaling pathway,down-regulation of TRAF6/NF-κB signaling pathway,and an increase in the relative abundance of Lactobacillus_johnsonii and Ligilactobacillus_murinus play a protective role in liver.

STAT3-Dependent Effects of Polymeric Immunoglobulin Receptor in Regulating Interleukin-17 Signaling and Preventing Autoimmune Hepatitis

One-third of patients with autoimmune hepatitis(AIH)have cirrhosis at the time of diagnosis.The relevance of these variables,although unknown,is believed to be critical in AIH because of suspected interactions between the gut microbiome and genetic factors.Dysbiosis of the gut flora and elevated polymeric immunoglobulin receptor(pIgR)levels have been observed in both patients and mouse models.Moreover,there is a direct relationship between pIgR expression and transaminase levels in patients with AIH.In this study,we aimed to explore how pIgR influences the secretion of regenerating islet-derived 3 beta(Reg3b)and the flora composition in AIH using in vivo experiments involving patients with AIH and a concanavalin A-induced mouse model of AIH.Reg3b expression was reduced in pIgR gene(Pigr)-knockout mice compared to that in wild-type mice,leading to increased microbiota disruption.Conversely,exogenous pIgR supplementation increased Reg3b expression and maintained microbiota homeostasis.RNA sequencing revealed the participation of the interleukin(IL)-17 signaling pathway in the regulation of Reg3b through pIgR.Furthermore,the introduction of external pIgR could not restore the imbalance in gut microbiota in AIH,and the decrease in Reg3b expression was not apparent following the inhibition of signal transducer and activator of transcription 3(STAT3).In this study,pIgR facilitated the upregulation of Reg3b via the STAT3 pathway,which plays a crucial role in preserving the balance of the intestinal microbiota in AIH.Through this research,we discovered new molecular targets that can be used for the diagnosis and treatment of AIH.

Advancements in autoimmune hepatitis management:Perspectives for future guidelines

The first-line treatment for autoimmune hepatitis involves the use of prednisone or prednisolone either as monotherapy or in combination with azathioprine(AZA).Budesonide has shown promise in inducing a complete biochemical response(CBR)with fewer adverse effects and is considered an optional first-line treatment,particularly for patients without cirrhosis;however,it is worth noting that the design of that study favored budesonide.A recent real-life study revealed higher CBR rates with prednisone when equivalent initial doses were administered.Current guidelines recommend mycophenolate mofetil(MMF)for patients who are intolerant to AZA.It is important to mention that the evidence supporting this recommendation is weak,primarily consisting of case series.Nevertheless,MMF has demonstrated superiority to AZA in the context of renal transplant.Recent comparative studies have shown higher CBR rates,lower therapeutic failure rates,and reduced intolerance in the MMF group.These findings may influence future guidelines,potentially leading to a significant modification in the first-line treatment of autoimmune hepatitis.Until recently,the only alternative to corticosteroids was lifelong maintenance treatment with AZA,which comes with notable risks,such as skin cancer and lymphoma.Prospective trials are essential for a more comprehensive assessment of treatment suspension strategies,whether relying on histological criteria,strict biochemical criteria,or a combination of both.Single-center studies using chloroquine diphosphate have shown promising results in significantly reducing relapse rates compared to placebo.However,these interesting findings have yet to be replicated by other research groups.Additionally,second-line drugs,such as tacrolimus,rituximab,and infliximab,should be subjected to controlled trials for further evaluation.

Immunological crossroads:The intriguing dance between hepatitis C and autoimmune hepatitis

Delving into the immunological crossroads of liver diseases,this editorial explores the dynamic interplay between hepatitis C virus(HCV)and autoimmune hepatitis(AIH).While HCV primarily manifests as a viral infection impacting the liver,previous studies unveil a captivating connection between HCV and the emergence of AIH.The dance of the immune system in response to HCV appears to set the stage for an intriguing phenomenon-an aberrant autoimmune response leading to the onset of AIH.Evidence suggests a heightened presence of autoimmune markers in individuals with chronic HCV infection,hinting at a potential overlap between viral and autoimmune liver diseases.Navigating the intricate terrain of viral replication,immune response dynamics,and genetic predisposition,this editorial adds a layer of complexity to our understanding of the relationship between HCV and AIH.In this immunological crossroads,we aim to unearth insights into the complex interplay,using a compelling case where AIH and primary sclerosing cholangitis overlapped following HCV treatment with direct-acting antivirals as background.

Research progress on the mechanism of traditional Chinese medicine in the treatment of autoimmune hepatitis

Autoimmune hepatitis is an inflammatory liver disease primarily mediated by T cell.It has not been fully elucidated about the pathogenesis,and it is presently thought to be related to genetic susceptibility,infection and environmental triggers,and abnormal autoimmune regulation.Recent studies have found that traditional Chinese medicine can improve the biochemical indicators and clinical symptoms of patients with autoimmune hepatitis.This article reviews the specific mechanism of traditional Chinese medicine on treating autoimmune hepatitis in order to propose new ideas for its clinical diagnosis and treatment.

Autoimmune hepatitis,one disease with many faces:Etiopathogenetic,clinico-laboratory and histological characteristics

Autoimmune hepatitis(AIH) is an unresolving progressive liver disease of unknown etiology characterized byhypergammaglobulinemia,autoantibodies detection and interface hepatitis.Due to the absence of specific diagnostic markers and the large heterogeneity of its clinical,laboratory and histological features,AIH diagnosis may be potentially difficult.Therefore,in this in-depth review we summarize the substantial progress on etiopathogenesis,clinical,serological and histological phenotypes of AIH.AIH has a global distribution affecting any age,both sexes and all ethnic groups.Clinical manifestations vary from asymptomatic to severe or rarely fulminant hepatitis.Hypergammaglobulinemia with selective elevation of IgG is found in most cases.Autoimmune attack is perpetuated,possibly via molecular mimicry,and favored by the impaired control of T-regulatory cells.Histology(interface hepatitis,emperipolesis and hepatic rosette formation) and autoantibodies detection although not pathognomonic,are still the hallmark for a timely diagnosis.AIH remains a major diagnostic challenge.AIH should be considered in every case in the absence of viral,metabolic,genetic and toxic etiology of chronic or acute hepatitis.Laboratory personnel,hepato-pathologists and clinicians need to become more familiar with disease expressions and the interpretation of liver histology and autoimmune serology to derive maximum benefit for the patient.

drug-induced autoimmune liver disease:a diagnostic dilemma of an increasingly reported disease

The aetiology of autoimmune hepatitis(AIH) is uncer-tain but the disease can be triggered in susceptible patients by external factors such as viruses or drugs.AIH usually develops in individuals with a genetic back-ground mainly consisting of some risk alleles of the major histocompatibility complex(HLA).Many drugs have been linked to AIH phenotypes,which sometimes persist after drug discontinuation,suggesting that they awaken latent autoimmunity.At least three clini-cal scenarios have been proposed that refers to drug- induced autoimmune liver disease(DIAILD):AIH with drug-induced liver injury(DILI); drug induced-AIH(DI-AIH); and immune mediated DILI(IM-DILI).In addi-tion,there are instances showing mixed features of DI-AIH and IM-DILI,as well as DILI cases with positive autoantibodies.Histologically distinguishing DILI from AIH remains a challenge.Even more challenging is the differentiation of AIH from DI-AIH mainly relying in histological features; however,a detailed standard-ised histologic evaluation of large cohorts of AIH and DI-AIH patients would probably render more subtle features that could be of help in the differential diag-nosis between both entities.Growing information on the relationship of drugs and AIH is being available,being drugs like statins and biologic agents more fre-quently involved in cases of DIAILD.In addition,there is some evidence on the fact that patients diagnosed with DIAILD may have had a previous episode of hepa-totoxicity.Further collaborative studies in DIAILD will strengthen the knowledge and understanding of this intriguing and complex disorder which might represent different phenotypes across the spectrum of

Autoimmune hepatitis and anti-tumor necrosis factor alpha therapy:A single center report of 8 cases

This article describes cases of anti-tumor necrosis factor(TNF)-α-induced autoimmune hepatitis and evaluates the outcome of these patients in relation to their immunosuppressive strategy. A retrospective analysis of medical records was performed in our center, in order to detect cases of autoimmune hepatitis(AIH) associated with anti-TNF biologic agents. We describe and analyze eight cases of AIH following anti-TNF therapy, 7 with infliximab and 1 with adalimumab. A distinction should be made between induction of autoimmunity and clinically evident autoimmune disease. Liver biopsy is useful in detecting the role of the TNF-α antagonist in the development of AIH. The lack of relapse after discontinuing immunosuppressive therapy favors, as in this case series, an immune-mediated drug reaction as most patients with AIH have a relapse after treatment is suspended. Although AIH related to anti-TNF therapy is rare, a baseline immunological panel along with liver function tests should be performed in all patients with autoimmune disease before starting biologics.

Autoimmune hepatitis and IgG4-related disease

IgG4-related disease(IgG4-RD) is a chronic-fibroinflammatory disorder affecting a wide range of organs. Elevation of serum IgG4 concentrations and abundant infiltration of IgG4-expressing plasma cells are key diagnostic features of this autoimmune disease. Although common organ involvement of IgG4-RD includes the salivary glands, pancreas, and bile duct, hepatic involvement is less well established. Recently, five studies identified a subtype of autoimmune hepatitis(AIH), called IgG4-associated AIH(IgG4-AIH). IgG4-AIH is diagnosed based on significant accumulation of IgG4-expressing plasmacytes in the liver in patients who met the diagnostic criteria for classical AIH. Although four of the five reports regarded IgG4-AIH based on hepatic accumulation of IgG4-positive cells alone, one report diagnosed IgG4-AIH based on both hepatic accumulation of IgG4-positive cells and elevated serum concentrations of IgG4. IgG4-AIH diagnosed based on the latter criteria may be a hepatic manifestation of IgG4-RD whereas IgG4-AIH diagnosed based on the former criteria may be a subtype of AIH. In this review article, we summarize and discuss clinicopathological features of IgG4-AIH.

Potential triggering factors of acute liver failure as a first manifestation of autoimmune hepatitis-a single center experience of 52 adult patients

AIM To investigate potential triggering factors leading to acute liver failure(ALF) as the initial presentation of autoimmune hepatitis(AIH).METHODS A total of 565 patients treated at our Department between 2005 and 2017 for histologically-proven AIH were retrospectively analyzed. However, 52 patients(9.2%) fulfilled the criteria for ALF defined by the "American Association for the Study of the Liver(AASLD)". According to this definition, patients with "acute-on-chronic" or "acute-on-cirrhosis" liver failure were excluded. Following parameters with focus on potential triggering factors were evaluated: Patients' demographics, causation of liver failure, laboratory data(liver enzymes, MELD-score, autoimmune markers, virus serology), liver histology, immunosuppressive regime, and finally, outcome of our patients.RESULTS The majority of patients with ALF were female(84.6%) and mean age was 43.6 ± 14.9 years. Interestingly, none of the patients with ALF was positive for antiliver kidney microsomal antibody(LKM). We could identify potential triggering factors in 26/52(50.0%) of previously healthy patients presenting ALF as their first manifestation of AIH. These were drug-induced ALF(57.7%), virus-induced ALF(30.8%), and preceding surgery in general anesthesia(11.5%), respectively. Unfortunately, 6 out of 52 patients(11.5%) did not survive ALF and 3 patients(5.7%) underwent liver transplantation(LT). Comparing data of survivors and patients with non-recovery following treatment, MELDscore(P < 0.001), age(P < 0.05), creatinine(P < 0.01), and finally, ALT-values(P < 0.05) reached statistical significance. CONCLUSION Drugs, viral infections, and previous surgery may trigger ALF as the initial presentation of AIH. Advanced age and high MELD-score were associated with lethal outcome.

Autoimmune hepatitis: standard treatment and systematic review of alternative treatments

Autoimmune hepatitis is a rare chronic inflammatory liver disease,affecting all ages,characterised by elevated transaminase and immunoglobulin G levels,positive autoantibodies,interface hepatitis at liver histology and good response to immunosuppressive treatment. If untreated,it has a poor prognosis. The aim of this review is to summarize the evidence for standard treatment and to provide a systematic review on alternative treatments for adults and children. Standard treatment is based on steroids and azathioprine,and leads to disease remission in 80%-90% of patients. Alternative first line treatment has been attempted with budesonide or cyclosporine,but their superiority compared to standard treatment remains to be demonstrated. Second-line treatments are needed for patients not responding or intolerant to standard treatment. No randomized controlled trials have been performed for second-line options. Mycophenolate mofetil is the most widely used second-line drug,and has good efficacy particularly for patients intolerant to azathioprine,but has the major disadvantage of being teratogenic. Only few and heterogeneous data on cyclosporine,tacrolimus,everolimus and sirolimus are available. More recently,experience with the anti-tumour necrosis factoralpha infliximab and the anti-CD20 rituximab has been published,with ambivalent results; these agents may have severe side-effects and their use should be restricted to specialized centres. Clinical trials with new therapeutic options are ongoing.

A serum metabolomic analysis for diagnosis and biomarker discovery of primary biliary cirrhosis and autoimmune hepatitis

Because of the diversity of the dinical and laboratory manifestations, the diagnosis of autoimmune liver disease （AILD） remains a challenge in clinical practice. The value of metabolomics has been studied in the diagnosis of many diseases. The present study aimed to determine whether the metabolic profiles, based on ultraperformance liquid chromatography-mass spectrometry （UPLC-MS）, differed between autoimmune hepatitis （AIH） and primary biliary cir- rhosis （PBC）, to identify specific metabolomic markers, and to establish a model for the diagnosis of AIH and PBC. METHODS： Serum samples were collected from 20 patients with PBC, 19 patients with AIH, and 25 healthy individuals. UPLC-MS data of the samples were analyzed using principal component analysis, partial least squares discrimination analysis and or- thogonal partial least squares discrimination analysis. RESULTS： The partial least squares discrimination analysis model （R2y=0.991, Q2=0.943） was established between the AIH and PBC groups and exhibited both sensitivity and speci- ficity of 100%. Five groups of biomarkers were identified, in- eluding bile acids, free fatty acids, phosphatidylcholines, lyso- lecithins and sphingomyelin. Bile acids significantly increased in the AIH and PBC groups compared with the healthy con- trol group. The other biomarkers decreased in the AIH andPBC groups compared with those in the healthy control group. In addition, the biomarkers were downregulated in the AIH group compared with the PBC group. CONCLUSIONS： The biomarkers identified revealed the pathophysiological changes in AILD and helped to discrimi- nate between AIH and PBC. The predictability of this method suggests its potential application in the diagnosis of AILD.

Useful biomarkers for assessment of hepatitis C virus infection-associated autoimmune disorders

During the course of chronic hepatitis C virus(HCV)infection,various extrahepatic manifestations of autoimmune disorders may occur,including arthralgia/arthritis,sicca complex,purpura,cutaneous ulcer,and thyroid dysfunction.In addition,the prevalence of circulating autoantibodies is high among patients with HCV infection.Commonly detected autoantibodies in HCVinfected patients include rheumatoid factor,antinuclear antibody,anti-SSA/anti-SSB antibody,cryoglobulin,antineutrophil cytoplasmic antibody,anti-smooth muscle antibody,anti-liver and anti-thyroid autoantibodies.These autoantibodies may be associated with underlying autoimmune disorders or liver inflammation in HCV infection.A possible reason for antibody production is overactivation and proliferation of B lymphocytes,via the interaction with the surface protein of HCV.Because immunotherapy can cause HCV flare-up or liver damage,overdiagnosis of HCV-related autoimmune symptoms as primary autoimmune disorders should be avoided.This review describes biomarkers that are useful in clinically evaluating autoimmune manifestations and disorders associated with HCV infection.

Examining pathogenic concepts of autoimmune hepatitis for cues to future investigations and interventions

BACKGROUND Multiple pathogenic mechanisms have been implicated in autoimmune hepatitis,but they have not fully explained susceptibility,triggering events,and maintenance or escalation of the disease.Furthermore,they have not identified a critical defect that can be targeted.The goals of this review are to examine the diverse pathogenic mechanisms that have been considered in autoimmune hepatitis,indicate investigational opportunities to validate their contribution,and suggest interventions that might evolve to modify their impact.English abstracts were identified in PubMed by multiple search terms.Full length articles were selected for review,and secondary and tertiary bibliographies were developed.Genetic and epigenetic factors can affect susceptibility by influencing the expression of immune regulatory genes.Thymic dysfunction,possibly related to deficient production of programmed cell death protein-1,can allow autoreactive T cells to escape deletion,and alterations in the intestinal microbiome may help overcome immune tolerance and affect gender bias.Environmental factors may trigger the disease or induce epigenetic changes in gene function.Molecular mimicry,epitope spread,bystander activation,neo-antigen production,lymphocytic polyspecificity,and disturbances in immune inhibitory mechanisms may maintain or escalate the disease.Interventions that modify epigenetic effects on gene expression,alter intestinal dysbiosis,eliminate deleterious environmental factors,and target critical pathogenic mechanisms are therapeutic possibilities that might reduce risk,individualize management,and improve outcome.In conclusion,diverse pathogenic mechanisms have been implicated in autoimmune hepatitis,and they may identify a critical factor or sequence that can be validated and used to direct future management and preventive strategies.