Immunosuppressive Treatment Regimens in Autoimmune Hepatitis: Systematic Reviews and Meta-Analyses Supporting American Association for the Study of Liver Diseases Guidelines

British Society of Gastroenterology guidelines for diagnosis and management of autoimmune hepatitis

Autoimmune hepatitis (AIH) is a chronic inflammatory liver disease which, if untreated, often leads to cirrhosis, liver failure and death. The last British Society of Gastroenterology (BSG) guideline for the management of AIH was published in 2011. Since then, our understanding of AIH has advanced in many areas. This update to the previous guideline was commissioned by the BSG and developed by a multidisciplinary group. The aim of this guideline is to review and summarise the current evidence, in order to inform and guide diagnosis and management of patients with AIH and its variant syndromes. The main focus is on AIH in adults, but the guidelines should also be relevant to older children and adolescents.

What is the optimal first-line treatment of autoimmune hepatitis? A systematic review with meta-analysis of randomised trials and comparative cohort studies

OBJECTIVES

Uncertainty remains about many aspects of first-line treatment of autoimmune hepatitis (AIH).

DESIGN

Systemic review with meta-analysis (MA).

DATA SOURCES

Bespoke AIH Endnote Library, updated to 30 June 2024.

ELIGIBILITY CRITERIA

Randomised controlled trials (RCTs) and comparative cohort studies including adult patients with AIH, reporting death/transplantation, biochemical response (BR) and/or adverse effects (AEs).

DATA EXTRACTION AND SYNTHESIS

Data pooled in MA as relative risk (RR) under random effects. Risk of bias (ROB) assessed using Cochrane ROB-2 and ROBINS-1 tools.

RESULTS

From seven RCTs (five with low and two with some ROB) and 18 cohort studies (12 moderate ROB, six high for death/transplant), we found lower death/transplantation rates in (a) patients receiving pred+/-aza (vs no pred): overall (RR 0.38 (95% CI 0.20 to 0.74)), in patients without symptoms (0.38 (0.19-0.75)), without cirrhosis (0.30 (0.14-0.65)), and with decompensated cirrhosis (RR 0.38 (0.23-0.61)), and (b) patients receiving pred+aza (vs pred alone) (0.38 (0.22-0.65)). Patients receiving higher (vs lower) initial pred doses had similar BR rates (RR 1.07 (0.92-1.24)) and mortality (0.71 (0.25-2.05)) but more AEs (1.73 (1.17-2.55)). Patients receiving bud (vs pred) had similar BR rates (RR 0.99 (0.71-1.39)), with fewer cosmetic AEs (0.46 (0.34-0.62)). Patients receiving mycophenolate mofetil (MMF) (vs aza) had similar BR rates (RR 1.32 (0.73-2.38)) and fewer AEs requiring drug cessation (0.20 (0.09-0.43)).

CONCLUSIONS

Mortality is lower in pred-treated (vs untreated) patients, overall and in several subgroups, and in those receiving pred+aza (vs pred). Higher initial pred doses confer no clear benefit and cause more AEs. Bud (vs pred) achieves similar BR rates, with fewer cosmetic AEs. MMF (vs aza) achieves similar BR rates, with fewer serious AEs.

Cellular senescence and its pathogenic and therapeutic implications in autoimmune hepatitis

INTRODUCTION

Senescent cells are characterized by replicative arrest and phenotypes that produce diverse pro-inflammatory and pro-oxidant mediators. The senescence of diverse hepatic cell types could constitute an unrecognized pathogenic mechanism and prognostic determinant in autoimmune hepatitis. The impact of cellular senescence in autoimmune hepatitis is unknown, and it may suggest adjunctive management strategies.

AREAS COVERED

This review describes the molecular mechanisms of cellular senescence, indicates its diagnostic features, suggests its consequences, presents possible therapeutic interventions, and encourages investigations of its pathogenic role and management in autoimmune hepatitis. Treatment prospects include elimination or reversal of senescent cells, generation of ectopic telomerase, reactivation of dormant telomerase, neutralization of specific pro-inflammatory secretory products, and mitigation of the effects of mitochondrial dysfunction.

EXPERT OPINION

The occurrence, nature, and consequences of cellular senescence in autoimmune hepatitis must be determined. The senescence of diverse hepatic cell types could affect the outcome of autoimmune hepatitis by impairing hepatic regeneration, intensifying liver inflammation, and worsening hepatic fibrosis. Cellular senescence could contribute to suboptimal responses during conventional glucocorticoid-based therapy. Interventions that target specific pro-inflammatory products of the senescent phenotype or selectively promote apoptosis of senescent cells may be preferred adjunctive treatments for autoimmune hepatitis depending on the cancer risk.

Prevalence of Acute on Chronic Liver Failure in Autoimmune Hepatitis, Treatment Response and Mortality Burden Assessment: A Region-Predominant Systematic Review and Meta-Analysis

Acute-on-chronic liver failure (ACLF) is a global health problem. Little scientific evidence exists on its prevalence in autoimmune hepatitis. Treatment response and mortality outcomes have also been reported differently. The study was conducted to estimate the overall prevalence of ACLF among patients with autoimmune hepatitis (AIH) and determine the associated treatment response and mortality. We scrutinized wide literature in Scopus, PubMed, Embase, Web of Science, and Cochrane, and assessed published articles completely, studies performed and reported from around the globe, until December 07, 2023, according to the PROSPERO registered protocol (CRD42023412176). Studies (retrospective and prospective cohort study type) that stated the ACLF development among established AIH cases were considered. Features of the study, duration of follow-up, and numeric patient information were retrieved from the studies included. The research paper quality was checked for risk of bias. Random effect meta-analysis with metaregression and subsection scrutinies were performed with R. The main outcome was the collective prevalence of ACLF in the AIH patients, whereas treatment response and mortality in AIH-associated ACLF were secondary outcomes. Six studies were involved with confirmed diagnoses in 985 AIH patients for the data synthesis. The pooled prevalence of ACLF in the explored patients was 12% (95% CI: 8-17) ( P =0.01). Heterogeneity was found to be high in the present meta-analysis ( I2 =72%; P < 0.01). For the secondary endpoint analysis, the pooled prevalence of complete remission at 1-year follow-up was 71% (0.52; 0.85), and mortality from the ACLF-AIH patient population was 32% (95% CI: 18-50). Sensitivity analysis showed no influence on the overall estimations of the pooled prevalence of ACLF by omitting studies one by one. One in 10 AIH patients likely present with ACLF. The response to treatment is seen in two-thirds of patients, and mortality is high.

Autoimmune hepatitis recurrence after liver transplantation: "Les jeux sont faits"

Autoimmune hepatitis (AIH) may recur after liver transplantation (LT). The aims of this study were to evaluate the incidence and risk factors for recurrent autoimmune hepatitis (rAIH). A multicenter retrospective French nationwide study, including all patients aged ≥16 transplanted for AIH, with at least 1 liver biopsy 1 year after LT, was conducted between 1985 and 2018. Risk factors for rAIH were identified using a multivariate Cox regression model. Three hundred and forty-four patients were included (78.8% women) with a median age at LT of 43.6 years. Seventy-six patients (22.1%) developed recurrence in a median time of 53.6 months (IQR, 14.1-93.2). Actuarial risk for developing rAIH was 41.3% 20 years after LT. In multivariate analysis, the strongest risk factor for rAIH was cytomegalovirus D+/R- mismatch status (HR=2.0; 95% CI: 1.1-3.6; p =0.03), followed by associated autoimmune condition. Twenty-one patients (27.6% of rAIH patients) developed liver graft cirrhosis after rAIH. Independent risk factors for these severe forms of rAIH were young age at LT, IgG levels >20.7 g/L, and LT in the context of (sub)fulminant hepatitis. Immunosuppression, especially long-term maintenance of corticosteroid therapy, was not significantly associated with rAIH. Recurrence of AIH after LT is frequent and may lead to graft loss. Recurrence is more frequent in young patients with active disease at the time of LT, yet systematic corticosteroid therapy does not prevent it.

Post-Transplant Management and Complications of Autoimmune Hepatitis, Primary Biliary Cholangitis, and Primary Sclerosing Cholangitis including Disease Recurrence

Autoimmune liver diseases have unique post-transplant considerations. These recipients are at increased risk of rejection, and recurrent disease may also develop, which can progress to graft loss and increase mortality. Monitoring for and managing these complications is therefore important, though data on associated risk factors and immunosuppression strategies has in most cases been mixed. There are also other disease-specific complications that require management and may impact these decisions, including inflammatory bowel disease in PSC. Further work to better understand the optimal management strategies for these patients post-transplant is needed.

Introducing Molecular Chaperones into the Causality and Prospective Management of Autoimmune Hepatitis

Molecular chaperones influence the immunogenicity of peptides and the activation of effector T cells, and their pathogenic roles in autoimmune hepatitis are unclear. Heat shock proteins are pivotal in the processing and presentation of peptides that activate CD8+ T cells. They can also induce regulatory B and T cells and promote immune tolerance. Tapasin and the transporter associated with antigen processing-binding protein influence the editing and loading of high-affinity peptides for presentation by class I molecules of the major histocompatibility complex. Their over-expression could enhance the autoimmune response, and their deficiency could weaken it. The lysosome-associated membrane protein-2a isoform in conjunction with heat shock cognate 70 supports the importation of cytosolic proteins into lysosomes. Chaperone-mediated autophagy can then process the peptides for activation of CD4+ T cells. Over-expression of autophagy in T cells may also eliminate negative regulators of their activity. The human leukocyte antigen B-associated transcript three facilitates the expression of class II peptide receptors, inhibits T cell apoptosis, prevents T cell exhaustion, and sustains the immune response. Immunization with heat shock proteins has induced immune tolerance in experimental models and humans with autoimmune disease by inducing regulatory T cells. Therapeutic manipulation of other molecular chaperones may promote T cell exhaustion and induce tolerogenic dendritic cells. In conclusion, molecular chaperones constitute an under-evaluated family of ancillary proteins that could affect the occurrence, severity, and outcome of autoimmune hepatitis. Clarification of their contributions to the immune mechanisms and clinical activity of autoimmune hepatitis could have therapeutic implications.

Incorporating the Molecular Mimicry of Environmental Antigens into the Causality of Autoimmune Hepatitis

Molecular mimicry between foreign and self-antigens has been implicated as a cause of autoimmune hepatitis in experimental models and cross-reacting antibodies in patients. This review describes the experimental and clinical evidence for molecular mimicry as a cause of autoimmune hepatitis, indicates the limitations and uncertainties of this premise, and encourages investigations that assess diverse environmental antigens as sources of disease-relevant molecular mimics. Pertinent articles were identified in PubMed using multiple search phrases. Several pathogens have linear or conformational epitopes that mimic the self-antigens of autoimmune hepatitis. The occurrence of an acute immune-mediated hepatitis after vaccination for severe acute respiratory syndrome (SARS)-associated coronavirus 2 (SARS-CoV-2) has suggested that vaccine-induced peptides may mimic disease-relevant tissue antigens. The intestinal microbiome is an under-evaluated source of gut-derived antigens that could also engage in molecular mimicry. Chaperone molecules may enhance the pathogenicity of molecular mimics, and they warrant investigation. Molecular mimics of immune dominant epitopes within cytochrome P450 IID6, the autoantigen most closely associated with autoimmune hepatitis, should be sought in diverse environmental antigens and assessed for pathogenicity. Avoidance strategies, dietary adjustments, vaccine improvement, and targeted manipulation of the intestinal microbiota may emerge as therapeutic possibilities. In conclusion, molecular mimicry may be a missing causality of autoimmune hepatitis. Molecular mimics of key immune dominant epitopes of disease-specific antigens must be sought in diverse environmental antigens. The ubiquity of molecular mimicry compels rigorous assessments of peptide mimics for immunogenicity and pathogenicity in experimental models. Molecular mimicry may complement epigenetic modifications as causative mechanisms of autoimmune hepatitis.

Open challenges in the management of autoimmune hepatitis

Autoimmune hepatitis (AIH) is a rare autoimmune disease of the liver with many open questions as regards its etiopathogenesis, natural history and clinical management. The classical picture of AIH is chronic hepatitis with fluctuating elevation of serum transaminases and Immunoglobulin G levels, the presence of circulating autoantibodies and typical histological features. However, atypical presentations do occur and are not well captured by current diagnostic scores, with important consequences in terms of missed diagnoses and delayed treatments. AIH is treated with corticosteroids and immunosuppressive drugs but up to 40% of patients do not achieve full biochemical response and are at risk of progressing to cirrhosis and liver failure. Moreover, standard therapies are associated by significant side-effects which may impair the quality of life of patients living with AIH. However, advances in the understanding of the underlying immunology of AIH is raising the prospect of novel therapies and optimization of existing therapeutic approaches to reduce side-effect burdens and potentially restore immunological tolerance. In this review we outlined the clinical characteristics, etiopathogenesis and management of AIH and current challenges in the diagnosis and management of AIH and provided evidence underlying the evolution of diagnostic and clinical management protocols.

Post-Transplant Immunosuppression in Autoimmune Liver Disease

Autoimmune liver diseases (AILDs) are a group of conditions where immune-mediated liver damage can lead to the need for transplantation. Collectively, they account for almost a quarter of all liver transplants. Outcomes in terms of graft and patient survival for all liver transplants have improved markedly over decades with improvements in patient selection, surgical techniques and longer-term care and this is also seen in patients with AILDs. The current five- and ten-year survival rates post-transplant in autoimmune disease are excellent, at 88% and 78%, respectively. A key factor in maintaining good outcomes post liver transplant for these autoimmune conditions is the immunosuppression strategy. These patients have increased the rates of rejection, and autoimmune conditions can all recur in the graft ranging from 12 to 60% depending on the population studied. Immunosuppressive regimens are centred on calcineurin inhibitors, often combined with low dose corticosteroids, with or without the addition of antimetabolite therapy. There is no clear evidence-based immunosuppressive regimen for these conditions, and a tailored approach balancing the individuals' immunological profile against the risks of immunosuppression is often used. There are disease-specific considerations to optimised graft function including the role of ursodeoxycholic acid in both primary biliary cholangitis and primary sclerosing cholangitis and the role and timing of colectomy in primary sclerosing cholangitis in inflammatory bowel disease patients. However, unmet needs still exist in the management of AILDs post liver transplantation particularly in building the evidence base for optimal immunosuppression as well as mitigating the risk of recurrent disease.

Long-term outcome of liver transplantation for autoimmune hepatitis: A French nationwide study over 30 years

BACKGROUND & AIMS

Autoimmune hepatitis (AIH) is a rare indication for liver transplantation (LT). The aims of this study were to evaluate long-term survival after LT for AIH and prognostic factors, especially the impact of recurrent AIH (rAIH).

METHODS

A multicentre retrospective nationwide study including all patients aged ≥16 transplanted for AIH in France was conducted. Early deaths and retransplantations (≤6 months) were excluded.

RESULTS

The study population consisted of 301 patients transplanted from 1987 to 2018. Median age at LT was 43 years (IQR, 29.4-53.8). Median follow-up was 87.0 months (IQR, 43.5-168.0). Seventy-four patients (24.6%) developed rAIH. Graft survival was 91%, 79%, 65% at 1, 10 and 20 years respectively. Patient survival was 94%, 84% and 74% at 1, 10 and 20 years respectively. From multivariate Cox regression, factors significantly associated with poorer patient survival were patient age ≥58 years (HR = 2.9; 95% CI, 1.4-6.2; p = 0.005) and occurrence of an infectious episode within the first year after LT (HR = 2.5; 95% CI, 1.2-5.1; p = 0.018). Risk factors for impaired graft survival were: occurrence of rAIH (HR = 2.7; 95% CI, 1.5-5.0; p = 0.001), chronic rejection (HR = 2.9; 95% CI, 1.4-6.1; p = 0.005), biliary (HR = 2.0; 95% CI, 1.2-3.4; p = 0.009), vascular (HR = 1.8; 95% CI, 1.0-3.1; p = 0.044) and early septic (HR = 2.1; 95% CI, 1.2-3.5; p = 0.006) complications.

CONCLUSION

Our results confirm that survival after LT for AIH is excellent. Disease recurrence and chronic rejection reduce graft survival. The occurrence of an infectious complication during the first year post-LT identifies at-risk patients for graft loss and death.

Calcineurin Inhibitors in the Treatment of Adult Autoimmune Hepatitis: A Systematic Review

BACKGROUND AND AIMS

A considerable number of autoimmune hepatitis (AIH) patients completely or partially fail on first-line treatment. Several studies on the use of calcineurin inhibitors (CNIs) in the treatment of AIH have been published without focusing on indication. The aim was to assess the efficacy of CNIs in the treatment of adult AIH patients, specifically focusing on indication: first-line intolerant and with first-line insufficient response (failure to achieve or maintain remission), and with second versus third-line treatment.

METHODS

A literature search included studies on the use of CNIs in adult AIH. Patients with past or present use of CNIs from the Dutch AIH group cohort were added. The primary endpoint was biochemical remission while using CNIs. Secondary endpoints were biochemical response, treatment failure, and adverse effects.

RESULTS

Twenty studies from the literature and nine Dutch patients were included describing the use of cyclosporine in 59 and tacrolimus in 219 adult AIH patients. The CNI remission rate was 53% in patients with insufficient response to first-line treatment and 67% in patients intolerant to first-line treatment. CNIs were used as second-line treatment in 73% with a remission rate of 52% and as third-line treatment in 22% with a remission rate of 26%. Cyclosporine was discontinued in 13% and tacrolimus in 11% of patients because of adverse events.

CONCLUSIONS

CNIs as rescue treatment in adult AIH patients are reasonably effective and safe both with insufficient response or intolerance to previous treatment. Prospective studies are needed.

Advancing Biologic Therapy for Refractory Autoimmune Hepatitis

Biologic agents may satisfy an unmet clinical need for treatment of refractory autoimmune hepatitis. The goals of this review are to present the types and results of biologic therapy for refractory autoimmune hepatitis, indicate opportunities to improve and expand biologic treatment, and encourage comparative clinical trials. English abstracts were identified in PubMed by multiple search terms. Full-length articles were selected for review, and secondary and tertiary bibliographies were developed. Rituximab (monoclonal antibodies against CD20 on B cells), infliximab (monoclonal antibodies against tumor necrosis factor-alpha), low-dose recombinant interleukin 2 (regulatory T cell promoter), and belimumab (monoclonal antibodies against B cell activating factor) have induced laboratory improvement in small cohorts with refractory autoimmune hepatitis. Ianalumab (monoclonal antibodies against the receptor for B cell activating factor) is in clinical trial. These agents target critical pathogenic pathways, but they may also have serious side effects. Blockade of the B cell activating factor or its receptors may disrupt pivotal B and T cell responses, and recombinant interleukin 2 complexed with certain interleukin 2 antibodies may selectively expand the regulatory T cell population. A proliferation-inducing ligand that enhances T cell proliferation and survival is an unevaluated, potentially pivotal, therapeutic target. Fully human antibodies, expanded target options, improved targeting precision, more effective delivery systems, and biosimilar agents promise to improve efficacy, safety, and accessibility. In conclusion, biologic agents target key pathogenic pathways in autoimmune hepatitis, and early experiences in refractory disease encourage clarification of the preferred target, rigorous clinical trial, and comparative evaluations.

Autoimmune hepatitis and metabolic syndrome-associated disease development: a U.S. cohort study

BACKGROUND

Autoimmune hepatitis (AIH) may coexist with metabolic syndrome-associated diseases (MSADs) given patients' inherent need for corticosteroid therapy, as well as general population trends.

AIM

To examine the impact of MSAD risk factors on AIH or its treatment, and vice versa METHODS: This was a multi-centre retrospective cohort study of 552 patients with AIH diagnosed between January 2000 and December 2019. Data relating to demographic factors, laboratory values, AIH medications and MSADs were collected at diagnosis and at 1- and 3-year follow-up. Statistical relationships were analysed and reported.

RESULTS

We included 552 patients in the study cohort (median age 50 years, 76.1% female). All MSADs, including hypertension, dyslipidaemia, diabetes and a gain of BMI ≥3 kg/m² , increased within the AIH cohort over time. Initial treatment regimen impacted de novo diabetes but not other MSAD development. AIH biochemical remission was less frequent at 3 years post-diagnosis among patients with ≥1 MSAD. The incidence of new MSADs could be predicted by baseline factors in certain cases.

CONCLUSION

In the largest US-based cohort of patients newly diagnosed with AIH, there was a considerable burden of pre-existing and de novo MSADs that may affect AIH treatment outcomes. Identifying those at highest risk of co-morbid MSADs allows for an individualised approach to management to reduce its long-term sequelae in patients with AIH.

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.

Lamina propria interleukin 17 A aggravates natural killer T-cell activation in autoimmune hepatitis

Autoimmune hepatitis is an interface hepatitis characterized by the progressive destruction of the liver parenchyma, the cause of which is still obscure. Interleukin (IL)-17A is a major driver of autoimmunity, which can be produced by innate immune cells against several intracellular pathogens. Here, we investigated the involvement of IL-17A in a mice model of immune-mediated hepatitis with the intestine exposed to Salmonella typhimurium. Our results showed more severe Concanavalin (Con) A-induced liver injury and gut microbiome dysbiosis when the mice were treated with a gavage of S. typhimurium. Then, the natural killer (NK) T cells were overactivated by the accumulated IL-17A in the liver in the Con A and S. typhimurium administration group. IL-17A could activate NKT cells by inducing CD178 expression via IL-4/STAT6 signaling. Furthermore, via the portal tract, the laminae propria mucosal-associated invariant T (MAIT)-cell-derived IL-17A could be the original driver of NKT cell overactivation in intragastric administration of S. typhimurium and Con A injection. In IL-17A-deficient mice, Con A-induced liver injury and NKT cell activation were alleviated. However, when AAV-sh-mIL-17a was used to specifically knock down IL-17A in liver, it seemed that hepatic IL-17a knock down did not significantly influence the liver injury. Our results suggested that, under Con A-induction, laminae propria MAIT-derived IL-17A activated hepatic NKT, and this axis could be a therapeutic target in autoimmune liver disease.

Examining micro-ribonucleic acids as diagnostic and therapeutic prospects in autoimmune hepatitis

INTRODUCTION

Micro-ribonucleic acids modulate the immune response by affecting the post-transcriptional expression of genes that influence the proliferation and function of activated immune cells, including regulatory T cells. Individual expressions or patterns in peripheral blood and liver tissue may have diagnostic value, reflect treatment response, or become therapeutic targets. The goals of this review are to present the properties and actions of micro-ribonucleic acids, indicate the key individual expressions in autoimmune hepatitis, and describe prospective clinical applications in diagnosis and management.

AREAS COVERED

Abstracts were identified in PubMed using the search words "microRNAs", "microRNAs in liver disease", and "microRNAs in autoimmune hepatitis". The number of abstracts reviewed exceeded 2000, and the number of full-length articles reviewed was 108.

EXPERT OPINION

Individual micro-ribonucleic acids, miR-21, miR-122, and miR-155, have been associated with biochemical severity, histological grade of inflammation, and pivotal pathogenic mechanisms in autoimmune hepatitis. Antisense oligonucleotides that down-regulate deleterious individual gene expressions, engineered molecules that impair targeting of gene products, and drugs that non-selectively up-regulate the biogenesis of potentially deficient gene regulators are feasible treatment options. Micro-ribonucleic acids constitute an under-evaluated area in autoimmune hepatitis that promises to improve diagnosis, pathogenic concepts, and therapy.

Immune Inhibitory Properties and Therapeutic Prospects of Transforming Growth Factor-Beta and Interleukin 10 in Autoimmune Hepatitis

Transforming growth factor-beta and interleukin 10 have diverse immune inhibitory properties that have restored homeostatic defense mechanisms in experimental models of autoimmune disease. The goals of this review are to describe the actions of each cytokine, review their investigational use in animal models and patients, and indicate their prospects as interventions in autoimmune hepatitis. English abstracts were identified in PubMed by multiple search terms. Full-length articles were selected for review, and secondary and tertiary bibliographies were developed. Transforming growth factor-beta expands the natural and inducible populations of regulatory T cells, limits the proliferation of natural killer cells, suppresses the activation of naïve CD8⁺ T cells, decreases the production of interferon-gamma, and stimulates fibrotic repair. Interleukin 10 selectively inhibits the CD28 co-stimulatory signal for antigen recognition and impairs antigen-specific activation of uncommitted CD4⁺ and CD8⁺ T cells. It also inhibits maturation of dendritic cells, suppresses Th17 cells, supports regulatory T cells, and limits production of diverse pro-inflammatory cytokines. Contradictory immune stimulatory effects have been associated with each cytokine and may relate to the dose and accompanying cytokine milieu. Experimental findings have not translated into successful early clinical trials. The recombinant preparation of each agent in low dosage has been safe in human studies. In conclusion, transforming growth factor-beta and interleukin 10 have powerful immune inhibitory actions of potential therapeutic value in autoimmune hepatitis. The keys to their therapeutic application will be to match their predominant non-redundant function with the pivotal pathogenic mechanism or cytokine deficiency and to avoid contradictory immune stimulatory actions.

Pathogenesis of Autoimmune Hepatitis-Cellular and Molecular Mechanisms

Pediatric autoimmune liver disorders include autoimmune hepatitis (AIH), autoimmune sclerosing cholangitis (ASC), and de novo AIH after liver transplantation. AIH is an idiopathic disease characterized by immune-mediated hepatocyte injury associated with the destruction of liver cells, causing inflammation, liver failure, and fibrosis, typically associated with autoantibodies. The etiology of AIH is not entirely unraveled, but evidence supports an intricate interaction among genetic variants, environmental factors, and epigenetic modifications. The pathogenesis of AIH comprises the interaction between specific genetic traits and molecular mimicry for disease development, impaired immunoregulatory mechanisms, including CD4+ T cell population and Treg cells, alongside other contributory roles played by CD8+ cytotoxicity and autoantibody production by B cells. These findings delineate an intricate pathway that includes gene to gene and gene to environment interactions with various drugs, viral infections, and the complex microbiome. Epigenetics emphasizes gene expression through hereditary and reversible modifications of the chromatin architecture without interfering with the DNA sequence. These alterations comprise DNA methylation, histone transformations, and non-coding small (miRNA) and long (lncRNA) RNA transcriptions. The current first-line therapy comprises prednisolone plus azathioprine to induce clinical and biochemical remission. Further understanding of the cellular and molecular mechanisms encountered in AIH may depict their impact on clinical aspects, detect biomarkers, and guide toward novel, effective, and better-targeted therapies with fewer side effects.

Review article: targeting the B cell activation system in autoimmune hepatitis

BACKGROUND

The B cell activation system, consisting of B cell activating factor and a proliferation-inducing ligand, may have pathogenic effects in autoimmune hepatitis.

AIMS

To describe the biological actions of the B cell activation system, indicate its possible role in autoimmune diseases, and evaluate its prospects as a therapeutic target in autoimmune hepatitis METHODS: English abstracts were identified in PubMed by multiple search terms. Full length articles were selected for review, and secondary and tertiary bibliographies were developed.

RESULTS

The B cell activating factor is crucial for the maturation and survival of B cells, and it can co-stimulate T cell activation, proliferation, and survival. It can also modulate the immune response by inducing interleukin 10 production by regulatory B cells. A proliferation-inducing ligand modulates and diversifies the antibody response by inducing class-switch recombination in B cells. It can also increase the proliferation, survival, and antigen activation of T cells. These immune stimulatory actions can be modulated by inducing proliferation of regulatory T cells. The B cell activation system has been implicated in diverse autoimmune diseases, and therapeutic blockade is a management strategy now being evaluated in autoimmune hepatitis.

CONCLUSIONS

The B cell activation system has profound effects on B and T cell function in autoimmune diseases. Blockade therapy is being actively evaluated in autoimmune hepatitis. Clarification of the critical pathogenic components of the B cell activation system will improve the targeting, efficacy, and safety of blockade therapy in this disease.

Long Term Outcomes of Liver Transplantation For Patients With Autoimmune Hepatitis

BACKGROUND

Autoimmune hepatitis (AIH) is a rare indication for liver transplantation (LT). Data on the long-term outcomes of living-related LT for AIH are limited and inconsistent. The present study aimed to assess the long-term outcomes of deceased donor LT (DDLT) and living donor LT (LDLT) for AIH.

METHODS

All patients who received transplants for AIH-related cirrhosis from 2001 to 2018 were included in this study.

RESULTS

Seventy-four patients (31 male, 43 female) received LT. The average follow-up was 7.9 ± 6.9 years (median = 7.2 years), average age was 34.3 ± 13.8 years, and average Model for End-Stage Liver Disease (MELD) score was 23.6 ± 8.5. Thirty-six (49.3%) patients received a graft from a living donor, and 83% of patients were maintained on steroids. The 1-, 3-, 5-, and 10-year survival rates of patients were 91%, 89%, 87%, and 82% and of grafts were 89%, 88%, 86%, and 76%, respectively. In univariate analysis, MELD score (odds ratio [OR], 1.08; 95% confidence interval [CI], 1.01-1.17; P = .028), donor age (OR per 5 years, 1.45; 95% CI, 1.07-2.02; P = .021), donor type (OR LDLT vs DDLT, 0.19; 95% CI, 0.04-0.67; P = .017), and renal function (OR glomerular filtration rate <60 vs ≥60 mL/min/m2, 7.41; 95% CI, 1.88-31.25; P = .004) were significant predictors of graft survival; however, none of the factors remained significant in multivariate analysis.

CONCLUSION

We have shown the highest reported long-term survival rates in LT for AIH, including a large number of patients who underwent LDLT. Standardized management and immunosuppressive therapy, including the maintenance of a low-dose steroid protocol, may have contributed to this outcome.

Etiopathogenesis and Diagnostic Strategies in Autoimmune Hepatitis

Autoimmune hepatitis (AIH) is a chronic liver disease with the incidence of 10 to 17 per 100,000 people in Europe. It affects people of any age, but most often occurs in the 40-60 age group. The clinical picture is varied, from asymptomatic to severe acute hepatitis or liver failure. The disease onset is probably associated with the impaired function of T lymphocytes, the development of molecular mimicry, intestinal dysbiosis, or infiltration with low density neutrophils, which, alongside autoantibodies (i.e., ANA, ASMA), implicate the formation of neutrophil extracellular traps (NETs), as a component of the disease process, and mediate the inappropriate immune response. AIH is characterized with an increased activity of aminotransferases, elevated concentration of serum immunoglobulin G, the presence of circulating autoantibodies and liver inflammation. The result of the histological examination of the liver and the presence of autoantibodies, although not pathognomonic, still remain a distinguishing feature. The diagnosis of AIH determines lifelong treatment in most patients. The treatment is implemented to prevent the development of cirrhosis and end-stage liver failure. This work focuses mainly on the etiopathogenesis and diagnosis of AIH.

Exploring the Pathogenic Role and Therapeutic Implications of Interleukin 2 in Autoimmune Hepatitis

Interleukin 2 is essential for the expansion of regulatory T cells, and low-dose recombinant interleukin 2 has improved the clinical manifestations of diverse autoimmune diseases in preliminary studies. The goals of this review are to describe the actions of interleukin 2 and its receptor, present preliminary experiences with low-dose interleukin 2 in the treatment of diverse autoimmune diseases, and evaluate its potential as a therapeutic intervention in autoimmune hepatitis. English abstracts were identified in PubMed by multiple search terms. Full-length articles were selected for review, and secondary and tertiary bibliographies were developed. Interleukin 2 is critical for the thymic selection, peripheral expansion, induction, and survival of regulatory T cells, and it is also a growth factor for activated T cells and natural killer cells. Interleukin 2 activates the signal transducer and activator of transcription 5 after binding with its trimeric receptor on regulatory T cells. Immune suppressor activity is increased; anti-inflammatory interleukin 10 is released; pro-inflammatory interferon-gamma is inhibited; and activation-induced apoptosis of CD8⁺ T cells is upregulated. Preliminary experiences with cyclic injections of low-dose recombinant interleukin 2 in diverse autoimmune diseases have demonstrated increased numbers of circulating regulatory T cells, preserved regulatory function, improved clinical manifestations, and excellent tolerance. Similar improvements have been recognized in one of two patients with refractory autoimmune hepatitis. In conclusion, interferon 2 has biological actions that favor the immune suppressor functions of regulatory T cells, and low-dose regimens in preliminary studies encourage its rigorous investigation in autoimmune hepatitis.

Outcome of COVID-19 in Patients With Autoimmune Hepatitis: An International Multicenter Study

BACKGROUND AND AIMS

Data regarding outcome of COVID-19 in patients with autoimmune hepatitis (AIH) are lacking.

APPROACH AND RESULTS

We performed a retrospective study on patients with AIH and COVID-19 from 34 centers in Europe and the Americas. We analyzed factors associated with severe COVID-19 outcomes, defined as the need for mechanical ventilation, intensive care admission, and/or death. The outcomes of patients with AIH were compared to a propensity score-matched cohort of patients without AIH but with chronic liver diseases (CLD) and COVID-19. The frequency and clinical significance of new-onset liver injury (alanine aminotransferase > 2 × the upper limit of normal) during COVID-19 was also evaluated. We included 110 patients with AIH (80% female) with a median age of 49 (range, 18-85) years at COVID-19 diagnosis. New-onset liver injury was observed in 37.1% (33/89) of the patients. Use of antivirals was associated with liver injury (P = 0.041; OR, 3.36; 95% CI, 1.05-10.78), while continued immunosuppression during COVID-19 was associated with a lower rate of liver injury (P = 0.009; OR, 0.26; 95% CI, 0.09-0.71). The rates of severe COVID-19 (15.5% versus 20.2%, P = 0.231) and all-cause mortality (10% versus 11.5%, P = 0.852) were not different between AIH and non-AIH CLD. Cirrhosis was an independent predictor of severe COVID-19 in patients with AIH (P < 0.001; OR, 17.46; 95% CI, 4.22-72.13). Continuation of immunosuppression or presence of liver injury during COVID-19 was not associated with severe COVID-19.

CONCLUSIONS

This international, multicenter study reveals that patients with AIH were not at risk for worse outcomes with COVID-19 than other causes of CLD. Cirrhosis was the strongest predictor for severe COVID-19 in patients with AIH. Maintenance of immunosuppression during COVID-19 was not associated with increased risk for severe COVID-19 but did lower the risk for new-onset liver injury during COVID-19.

Management of Autoimmune Liver Diseases after Liver Transplantation

Autoimmune liver diseases are characterized by immune-mediated inflammation and eventual destruction of the hepatocytes and the biliary epithelial cells. They can progress to irreversible liver damage requiring liver transplantation. The post-liver transplant goals of treatment include improving the recipient’s survival, preventing liver graft-failure, and decreasing the recurrence of the disease. The keystone in post-liver transplant management for autoimmune liver diseases relies on identifying which would be the most appropriate immunosuppressive maintenance therapy. The combination of a steroid and a calcineurin inhibitor is the current immunosuppressive regimen of choice for autoimmune hepatitis. A gradual withdrawal of glucocorticoids is also recommended. On the other hand, ursodeoxycholic acid should be initiated soon after liver transplant to prevent recurrence and improve graft and patient survival in primary biliary cholangitis recipients. Unlike the previously mentioned autoimmune diseases, there are not immunosuppressive or disease-modifying agents available for patients with primary sclerosing cholangitis. However, colectomy and annual colonoscopy are key components during the post-liver transplant period.

[Chronic kidney injury in patients with liver diseases - Reappraising pathophysiology and treatment options]

Acute and chronic kidney disease concurs commonly with liver disease and is associated with a wide array of complications including dialysis dependency and increased mortality. Patients with liver disease or liver cirrhosis show a higher prevalence of chronic kidney disease. This is attributed to concomitant comorbidities, such as metabolic syndrome, chronic inflammation, hypercoagulability, hyperfibrinolysis, diabetes mellitus and dyslipidaemias. But chronic progressive kidney disease is not always due to hepatorenal syndrome. Beyond that, other diseases or disease entities should be considered. Among them are diabetic nephropathy, secondary IgA nephropathy, hepatitis C -associated membranoproliferative Glomerulonephritis (MPGN) and hepatitis B-associated membranous nephropathy.Coexisting diseases, similar underlying pathophysiologic mechanisms, or simultaneously concurring pathophysiological processes and overlapping clinical manifestations, impede the etiologic diagnosis and corresponding treatment of chronic kidney disease in the setting of chronic liver disease. In this review, we focus on common and rare pathologies, which can lead to chronic kidney disease in this particular patient group and try to summarize the most recent therapeutic modalities.

Recent updates on the management of autoimmune hepatitis

Autoimmune hepatitis (AIH) is an immunoinflammatory chronic liver disease with dynamic and rather heterogeneous disease manifestations. A trend of increasing prevalence of AIH has been observed worldwide, along with a relative increase in the percentage of male patients. AIH is characterized and diagnosed based on serum biochemistry and liver histology: elevated aminotransferases and serum immunoglobulin G (IgG), the presence of serum anti-nuclear antibody or anti-smooth muscle antibody, and interface lympho-plasmacytic hepatitis. Clinical manifestations differ among disease subtypes with distinct time-frames, i.e., AIH with a chronic insidious onset, and acute-onset AIH (the diagnosis of which is often challenging due to the lack of typical serum findings). The absence of disease-specific biomarkers or histological findings may expand the disease phenotype into drug-induced AIH-like liver injury. Corticosteroids and azathioprine are recommended first-line treatments for AIH. The complete normalization of aminotransferases and serum IgG is an essential treatment response to ensure long-term overall survival. An incomplete response or intolerance to these drugs is considered an indication for second-line treatment, especially with mycophenolate mofetil. Life-long maintenance treatment is required for the majority of patients, but the few who achieve prolonged and stringent biochemical remission with lower alanine aminotransferase and IgG within the normal range may be able to discontinue the medications. In the future, the quality of life of AIH patients should be managed by personalized medicine, including the appropriate selection and dosing of first-line therapy and perhaps alternating with potential therapeutics, and the prediction of the success of treatment withdrawal.

Review article: opportunities to improve and expand thiopurine therapy for autoimmune hepatitis

BACKGROUND

Thiopurines in combination with glucocorticoids are used as first-line, second-line and maintenance therapies in autoimmune hepatitis and opportunities exist to improve and expand their use.

AIMS

To describe the metabolic pathways and key factors implicated in the efficacy and toxicity of the thiopurine drugs and to indicate the opportunities to improve outcomes by monitoring and manipulating metabolic pathways, individualising dosage and strengthening the response.

METHODS

English abstracts were identified in PubMed by multiple search terms. Full-length articles were selected for review, and secondary and tertiary bibliographies were developed.

RESULTS

Thiopurine methyltransferase activity and 6-tioguanine (6-thioguanine) nucleotide levels influence drug efficacy and safety, and they can be manipulated to improve treatment response and prevent myelosuppression. Methylated thiopurine metabolites are associated with hepatotoxicity, drug intolerance and nonresponse and their production can be reduced or bypassed. Universal pre-treatment assessment of thiopurine methyltransferase activity and individualisation of dosage to manipulate metabolite thresholds could improve outcomes. Early detection of thiopurine resistance by metabolite testing, accurate estimations of drug onset and strength by surrogate markers and adjunctive use of allopurinol could improve the management of refractory disease. Dose-restricted tioguanine (thioguanine) could expand treatment options by reducing methylated metabolites, increasing the bioavailability of 6-tioguanine nucleotides and ameliorating thiopurine intolerance or resistance.

CONCLUSIONS

The efficacy and safety of thiopurines in autoimmune hepatitis can be improved by investigational efforts that establish monitoring strategies that allow individualisation of dosage and prediction of outcome, increase bioavailability of the active metabolites and demonstrate superiority to alternative agents.