De novo autoimmune hepatitis in Korean children after liver transplantation: a single institution's experience

HERV1-env Induces Unfolded Protein Response Activation in Autoimmune Liver Disease: A Potential Mechanism for Regulatory T Cell Dysfunction

Regulatory T cells (Tregs) are not terminally differentiated but can acquire effector properties. Here we report an increased expression of human endogenous retrovirus 1 (HERV1-env) proteins in Tregs of patients with de novo autoimmune hepatitis and autoimmune hepatitis, which induces endoplasmic reticulum (ER) stress. HERV1-env-triggered ER stress activates all three branches (IRE1, ATF6, and PERK) of the unfolded protein response (UPR). Our coimmunoprecipitation studies show an interaction between HERV1-env proteins and the ATF6 branch of the UPR. The activated form of ATF6α activates the expression of RORC and STAT3 by binding to promoter sequences and induces IL-17A production. Silencing of HERV1-env results in recovery of Treg suppressive function. These findings identify ER stress and UPR activation as key factors driving Treg plasticity (species: human).

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.

Recurrent and De Novo Autoimmune Hepatitis

Clinical indications for liver transplantation (LT) in patients with autoimmune hepatitis (AIH) are identical to those of patients with other chronic liver diseases that end in acute or semiacute liver failure, decompensated cirrhosis, or hepatocellular carcinoma. Recurrent disease after LT has been reported in 10%-50% of patients with AIH, and the frequency of detection is influenced in part by the use of protocol or clinically indicated liver biopsy. De novo AIH connotes the development of AIH in patients transplanted for liver diseases other than AIH, and it has been reported in 5%-10% of pediatric and 1%-2% of adult recipients. Recurrent disease can negatively impact on graft and patient survival, and retransplantation has been required in 8%-23%. De novo AIH is within the spectrum of graft dysfunction that includes plasma cell-rich rejection, and it can also progress to cirrhosis and graft failure. Treatment for recurrent or de novo disease is based on the conventional regimens for AIH, and corticosteroid therapy alone or combined with azathioprine is standard. Better control of disease activity prior to LT has been associated with less recurrence, and maintenance corticosteroid treatment after LT can reduce its frequency. In conclusion, recurrent AIH is far more frequent than de novo AIH. Both may have negative impacts on graft and patient survival, and early detection and treatment are key objectives. Future investigations must codify the diagnostic criteria for each graft dysfunction, seek diagnostic biomarkers, and evaluate treatments that improve outcomes without increasing the risk of pre- and post-LT infections.

Rethinking de novo immune hepatitis, an old concept for liver allograft rejection: Relevance of glutathione S-transferase T1 mismatch

Antibody-mediated rejection (AMR) in liver transplantation has long been underestimated. The concept of the liver as an organ susceptible to AMR has emerged in recent years, not only in the context of the major histocompatibility complex with the presence of HLA donor-specific antibodies, but also with antigens regarded as “minor”, whose role in AMR has been demonstrated. Among them, antibodies against glutathione S-transferase T1 have been found in 100% of patients with de novo autoimmune hepatitis (dnAIH) when studied. In its latest update, the Banff Working Group for liver allograft pathology proposed replacing the term dnAIH with plasma cell (PC)-rich rejection. Antibodies to glutathione S-transferase T1 (GSTT1) in null recipients of GSTT1 positive donors have been included as a contributory but nonessential feature of the diagnosis of PC-rich rejection. Also in this update, non-organ-specific anti-nuclear or smooth muscle autoantibodies are no longer included as diagnostic criteria. Although initially found in a proportion of patients with PC-rich rejection, the presence of autoantibodies is misleading since they are not disease-specific and appear in many different contexts as bystanders. The cellular types and proportions of the inflammatory infiltrates in diagnostic biopsies have been studied in detail very recently. PC-rich rejection biopsies present a characteristic cellular profile with a predominance of T lymphocytes and a high proportion of PCs, close to 30%, of which 16.48% are IgG4⁺. New data on the relevance of GSTT1-specific T lymphocytes to PC-rich rejection will be discussed in this review.

Current epidemiology and clinical characteristics of autoimmune liver diseases in South Korea

Autoimmune liver diseases including autoimmune hepatitis (AIH) and primary biliary cholangitis (PBC) are rare diseases. The aim of this review is to examine the epidemiology and clinical characteristics of AIH and PBC in South Korea. There were 4,085 patients registered as AIH in the Rare Intractable Disease Registry of Korea between 2009-2013, with a median age of 56 years and female-to male ratio of 6.4. The age-adjusted incidence and prevalence of AIH were 1.07/100,000/year and 4.82/100,000 persons, respectively. Among the patients, 1.1% underwent liver transplantation, and case fatality was 2.18%. Liver cirrhosis at diagnosis was accompanied in 23%; liver biopsy was performed in 75.2%, and prednisolone therapy or prednisolone and azathioprine combination therapy was done in 73% with a remission rate of 86%. There were 2,824 patients with PBC (≥20 years) registered in Korea between 2009-2013 with a median age of 57 years and female-to male ratio of 6.2. The age-adjusted incidence and prevalence of PBC were 0.86/100,000/year and 4.75/100,000 persons, respectively. Among the patients, 2.5% underwent liver transplantation, and case fatality was 2.2% with a 5-year transplantation-free survival of 95.4%. Ursodeoxycholic acid (UDCA) was prescribed in 90% of the patients with a UDCA inadequate response rate of 30%. In conclusion, AIH and PBC are rare but mostly treatable diseases if diagnosed in the early stages. However, scarce data, low awareness, delayed diagnosis and non-availability of 2nd line therapeutics are important issues to be solved. Therefore, governmental support for research and drug development and nationwide cooperative studies are warranted.

Autoimmune Hepatitis in the Liver Transplant Graft

Recurrent autoimmune hepatitis (AIH) and de novo AIH are 2 important causes of late graft failure after liver transplantation (LT). Recurrent AIH occurs in patients who undergo LT for AIH. De novo AIH occurs in patients who are transplanted for etiologies other than AIH. Although typically treated with standard treatment for AIH, including corticosteroids and azathioprine, both recurrent and de novo AIH may progress to end-stage liver disease requiring retransplantation.

Autoimmune Liver Disease Post-Liver Transplantation: A Summary and Proposed Areas for Future Research. Transplantation. 2016;100:515-524. [PMID: 26447505 PMCID: PMC4764021 DOI: 10.1097/tp.0000000000000922]

Autoimmune liver diseases (AILD) are rare diseases with a reported prevalence of less than 50 per 100 000 population. As the research landscape and our understanding of AILDs and liver transplantation evolves, there remain areas of unmet needs. One of these areas of unmet needs is prevention of disease recurrence after liver transplantation. Disease recurrence is not an insignificant event because allograft loss with the need for retransplantation can occur. Patients transplanted for AILD are more likely to experience acute rejection compared to those transplanted for non-AILD, and the reason(s) behind this observation is unclear. Tasks for the future include a better understanding of the pathogenesis of AILD, definition of the precise pathogenetic mechanisms of recurrent AILD, and development of strategies that can identify recipients at risk for disease recurrence. Importantly, the role of crosstalk between alloimmune responses and autoimmune responses in AILD is an important area that needs further study.

This article reviews the relevant literature of de novo autoimmune hepatitis, recurrent autoimmune hepatitis, recurrent primary sclerosing cholangitis, and recurrent primary biliary cirrhosis in terms of the clinical entity, the scientific advancements, and future scientific goals to enhance our understanding of these diseases.

A review of the relevant literature of de novo autoimmune hepatitis, recurrent autoimmune hepatitis, recurrent primary sclerosing cholangitis, and recurrent primary biliary cirrhosis in terms of the clinical entity, the scientific advancements and future scientific goals to enhance our understanding of these diseases.

De novo autoimmune hepatitis in liver transplant: State-of-the-art review

In the two past decades, a number of communications, case-control studies, and retrospective reports have appeared in the literature with concerns about the development of a complex set of clinical, laboratory and histological characteristics of a liver graft dysfunction that is compatible with autoimmune hepatitis. The de novo prefix was added to distinguish this entity from a pre-transplant primary autoimmune hepatitis, but the globally accepted criteria for the diagnosis of autoimmune hepatitis have been adopted in the diagnostic algorithm. Indeed, de novo autoimmune hepatitis is characterized by the typical liver necro-inflammation that is rich in plasma cells, the presence of interface hepatitis and the consequent laboratory findings of elevations in liver enzymes, increases in serum gamma globulin and the appearance of non-organ specific auto-antibodies. Still, the overall features of de novo autoimmune hepatitis appear not to be attributable to a univocal patho-physiological pathway because they can develop in the patients who have undergone liver transplantation due to different etiologies. Specifically, in subjects with hepatitis C virus recurrence, an interferon-containing antiviral treatment has been indicated as a potential inception of immune system derangement. Herein, we attempt to review the currently available knowledge about de novo liver autoimmunity and its clinical management.

Diagnosis and Management of Autoimmune Hepatitis: Current Status and Future Directions

Autoimmune hepatitis is characterized by autoantibodies, hypergammaglobulinemia, and interface hepatitis on histological examination. The features lack diagnostic specificity, and other diseases that may resemble autoimmune hepatitis must be excluded. The clinical presentation may be acute, acute severe (fulminant), or asymptomatic; conventional autoantibodies may be absent; centrilobular necrosis and bile duct changes may be present; and the disease may occur after liver transplantation or with features that suggest overlapping disorders. The diagnostic criteria have been codified, and diagnostic scoring systems can support clinical judgment. Nonstandard autoantibodies, including antibodies to actin, α-actinin, soluble liver antigen, perinuclear antineutrophil antigen, asialoglycoprotein receptor, and liver cytosol type 1, are tools that can support the diagnosis, especially in patients with atypical features. Prednisone or prednisolone in combination with azathioprine is the preferred treatment, and strategies using these medications in various doses can ameliorate treatment failure, incomplete response, drug intolerance, and relapse after drug withdrawal. Budesonide, mycophenolate mofetil, and calcineurin inhibitors can be considered in selected patients as frontline or salvage therapies. Molecular (recombinant proteins and monoclonal antibodies), cellular (adoptive transfer and antigenic manipulation), and pharmacological (antioxidants, antifibrotics, and antiapoptotic agents) interventions constitute future directions in management. The evolving knowledge of the pathogenic pathways and the advances in technology promise new management algorithms.

De novo autoimmune hepatitis following liver transplantation for primary biliary cirrhosis: an unusual cause of late grafts dysfunction

De novo autoimmune hepatitis (AIH) is a rare disorder first described in 1998. It occurs in patients who underwent liver transplantation for a different etiology. We present the case of a 56-year-old woman who was diagnosed with primary biliary cirrhosis and had liver transplantation for refractory pruritis. Seven years after transplantation, she presented alterations in the hepatic profile with hypertransaminasemia, elevated alkaline phosphatase and gamma-glutamyl-transferase. Her liver functions test also showed elevated IgG levels. Serum autoantibodies were negative except for antimitochondrial antibodies. Histological findings indicated features of AIH without bile duct damage or loss. She had a pretreatment AIH score of 13 points and a post treatment score of 15 points according to the International AIH Group. The patient was treated effectively with prednisolone and her liver function and globulin levels rapidly returned to normal.

Liver transplantation and autoimmune hepatitis

Liver Transplantation (LT) is an effective treatment for patients with end-stage liver disease including autoimmune hepatitis (AIH). Indication for LT for AIH does not differ basically from other liver diseases including both acute and chronic types of disease progression, although it is reported to be an infrequent indication for LT worldwide due to the therapeutic advances of immunosuppression. The outcome following LT is feasible, with current patient and graft survival exceeding 75% at 5 years. Recurrent and de-novo AIH posttranslant has also been reported; and this seems to have important clinical implications because its management differs from the standard treatment for allograft rejection. In this review, we discuss the characteristics of AIH, focusing on the indication for LT and issues raised following LT.

Autoimmune liver disease, autoimmunity and liver transplantation

Primary biliary cirrhosis (PBC), primary sclerosing cholangitis (PSC) and autoimmune hepatitis (AIH) represent the three major autoimmune liver diseases (AILD). PBC, PSC, and AIH are all complex disorders in that they result from the effects of multiple genes in combination with as yet unidentified environmental factors. Recent genome-wide association studies have identified numerous risk loci for PBC and PSC that host genes involved in innate or acquired immune responses. These loci may provide a clue as to the immune-based pathogenesis of AILD. Moreover, many significant risk loci for PBC and PSC are also risk loci for other autoimmune disorders, such type I diabetes, multiple sclerosis and rheumatoid arthritis, suggesting a shared genetic basis and possibly similar molecular pathways for diverse autoimmune conditions. There is no curative treatment for all three disorders, and a significant number of patients eventually progress to end-stage liver disease requiring liver transplantation (LT). LT in this context has a favourable overall outcome with current patient and graft survival exceeding 80% at 5years. Indications are as for other chronic liver disease although recent data suggest that while lethargy improves after transplantation, the effect is modest and variable so lethargy alone is not an indication. In contrast, pruritus rapidly responds. Cholangiocarcinoma, except under rigorous selection criteria, excludes LT because of the high risk of recurrence. All three conditions may recur after transplantation and are associated with a greater risk of both acute cellular and chronic ductopenic rejection. It is possible that a crosstalk between alloimmune and autoimmune response perpetuate each other. An immunological response toward self- or allo-antigens is well recognised after LT in patients transplanted for non-autoimmune indications and sometimes termed "de novo autoimmune hepatitis". Whether this is part of the spectrum of rejection or an autoimmune process is not clear. In this manuscript, we review novel findings about disease processes and mechanisms that lead to autoimmunity in the liver and their possible involvement in the immune response vs. the graft after LT.

Histologic findings predictive of a diagnosis of de novo autoimmune hepatitis after liver transplantation in adults. Transplantation. 2013;96:670-678. [PMID: 23982338 DOI: 10.1097/tp.0b013e31829eda7f]

BACKGROUND

Autoimmune hepatitis (AIH) after liver transplantation has been defined histologically as a "hepatitic" pattern of injury, characterized by lymphoplasmacytic inflammation with necroinflammatory activity (NIA), comparable with findings seen in native livers. This definition, however, is difficult to apply in practice because specific histologic criteria are not clearly delineated. This study aimed to determine which histologic features correlated best with clinical and serologic features of dAIH.

METHODS

Index liver biopsies from patients with autoimmune-like hepatitis transplanted for non-AIH in two centers (n=35 and 20) were reviewed. Histologic features were correlated with the clinical diagnosis of AIH based on a retrospective review of clinical and serologic data, including therapeutic response.

RESULTS

A clinical diagnosis of AIH was retrospectively assigned to 24 of 35 (68%) and 18 of 20 (90%) patients, respectively (P=0.10). In multivariate analysis, centrilobular NIA and centrilobular plasma cell (PC) ratio of 30% to 50% were independently discriminating for a clinical diagnosis of AIH (P=0.04 and 0.05, respectively). The best level of predictability (99.6%) was mathematically achieved when severe centrilobular NIA and centrilobular PC ratio of 30% to 50% were both present.

CONCLUSION

A histologic pattern of centrilobular injury including increased NIA and increased PC infiltration correlates with measurements of autoimmunity in liver recipients. It could be used to segregate cases for further study and introduced into the AIH scoring systems when applied in the context of liver transplantation.

Paediatric autoimmune liver disease

Autoimmune liver disorders in childhood include autoimmune hepatitis (AIH) and AIH/sclerosing cholangitis overlap syndrome (henceforth referred to as autoimmune sclerosing cholangitis, ASC). These inflammatory liver disorders are characterised histologically by interface hepatitis, biochemically by elevated transaminase levels, and serologically by autoantibodies and increased levels of immunoglobulin G. AIH is particularly aggressive in children and progresses rapidly unless immunosuppressive treatment is started promptly. With appropriate treatment, 80% of patients achieve remission and long-term survival. For non-responders and difficult-to-treat patients, novel and more effective therapeutic approaches are sought. ASC responds to the same treatment used for AIH in regards to parenchymal inflammation, but bile duct disease progresses in about 50% of cases, leading to a worse prognosis and a higher liver transplantation requirement; moreover, it has a high recurrence rate after transplant. Progression of liver disease and recurrence after transplant are more common in patients with associated poorly controlled inflammatory bowel disease. Though the mechanisms underlying the pathogenesis of liver autoimmunity are not fully understood, genetic and environmental factors are likely to be involved. A deeper understanding of the pathogenesis of these conditions will contribute to the development of novel treatments, aimed ultimately at the restoration of tolerance to liver-derived antigens.

Plasma cell hepatitis (de-novo autoimmune hepatitis) developing post liver transplantation. Curr Opin Organ Transplant. 2012;17:287-292. [PMID: 22498651 DOI: 10.1097/mot.0b013e3283536622]

PURPOSE OF REVIEW

Cases of de-novo autoimmune hepatitis/plasma cell hepatitis (PCH) are increasingly being diagnosed by liver transplant centers. Its pathogenesis is poorly understood but this entity appears to be a variant of rejection. Herein, we review recent clinical reports of patients developing PCH.

RECENT FINDINGS

Histologically, PCH is a challenging diagnosis, especially in the setting of recurrent hepatitis C and, in some cases, can be mistaken for acute cellular rejection. Recent case reports and case-control studies have shown that interferon appears to trigger PCH in hepatitis C posttransplant patients. Optimization of the immunosuppression regimen was found to prevent the development of PCH. In the nonhepatitis C posttransplant patient, tacrolimus-based immunosuppression appears to have some protective effect from PCH development. A combination therapy of cyclosporine and everolimus has also been shown to be effective in treating PCH.

SUMMARY

PCH is a variant of rejection and is a cause of late graft loss post liver transplantation, especially in patients with hepatitis C. It should be part of the differential diagnosis of abnormal liver enzyme tests occurring in the post-liver transplant setting.

Diagnosis, pathogenesis, and treatment of autoimmune hepatitis after liver transplantation

Autoimmune hepatitis can recur or appear de novo after liver transplantation, and it can result in hepatic fibrosis, graft loss, and re-transplantation. The goals of this review are to describe the prevalence, manifestations, putative pathogenic mechanisms, outcomes, and management of these occurrences. Autoimmune hepatitis recurs in 8-12 % of transplanted patients at 1 year and 36-68 % at 5 years. Recurrence may be asymptomatic and detected only by surveillance liver test abnormalities or protocol liver tissue examination. Autoantibodies that characterized the original disease, hypergammaglobulinemia, increased serum immunoglobulin G level, and histological findings of interface hepatitis, lymphoplasmacytic infiltration, perivenular hepatocyte necrosis, pseudo-rosetting, and acidophil bodies typify recurrence. Premature corticosteroid withdrawal and pre-transplant severity of the original disease are possible risk factors. De novo autoimmune hepatitis occurs in 1-7 % of patients 0.1-9 years after transplantation, especially in children. The appearance of autoantibodies may herald its emergence, and antibodies to glutathione-S-transferase T1 have been predictive of the disease. Recurrent disease may reflect recruitment of residual memory T lymphocytes and host-specific genetic predispositions, whereas de novo disease may reflect an allo-antigenic immune response and molecular mimicries that override self-tolerance. Treatment should be appropriate for autoimmune hepatitis and not based on anti-rejection drugs. Corticosteroid therapy alone or combined with azathioprine is the essential treatment. The substitution of mycophenolate mofetil for azathioprine and switch of the calcineurin inhibitor or its replacement with rapamycin have also been used for refractory disease. Re-transplantation has been necessary in 8-23 %.