Epigenetic considerations and the clinical reevaluation of the overlap syndrome between primary biliary cirrhosis and autoimmune hepatitis

Immunosuppression induces regression of fibrosis in primary biliary cholangitis with moderate-to-severe interface hepatitis

BACKGROUND

In patients with primary biliary cholangitis (PBC) treated with ursodeoxycholic acid (UDCA), the presence of moderate-to-severe interface hepatitis is associated with a higher risk of liver transplantation and death. This highlights the need for novel treatment approaches. In this study, we aimed to investigate whether combination therapy of UDCA and immunosuppressant (IS) was more effective than UDCA monotherapy.

METHODS

We conducted a multicenter study involving PBC patients with moderate-to-severe interface hepatitis who underwent paired liver biopsies. Firstly, we compared the efficacy of the combination therapy with UDCA monotherapy on improving biochemistry, histology, survival rates, and prognosis. Subsequently we investigated the predictors of a beneficial response.

RESULTS

This retrospective cohort study with prospectively collected data was conducted in China from January 2009 to April 2023. Of the 198 enrolled patients, 32 underwent UDCA monotherapy, while 166 received combination therapy, consisting of UDCA combined with prednisolone, prednisolone plus mycophenolate mofetil (MMF), or prednisolone plus azathioprine (AZA). The monotherapy group was treated for a median duration of 37.6 months (IQR 27.5-58.1), and the combination therapy group had a median treatment duration of 39.3 months (IQR 34.5-48.8). The combination therapy showed a significantly greater efficacy in reducing fibrosis compared to UDCA monotherapy, with an 8.3-fold increase in the regression rate (from 6.3% to 52.4%, P < 0.001). Other parameters, including biochemistry, survival rates, and prognosis, supported its effectiveness. Baseline IgG >1.3 × ULN and ALP <2.4 × ULN were identified as predictors of regression following the combination therapy. A predictive score named FRS, combining these variables, accurately identified individuals achieving fibrosis regression with a cut-off point of ≥ -0.163. The predictive value was validated internally and externally.

CONCLUSION

Combination therapy with IS improves outcomes in PBC patients with moderate-to-severe interface hepatitis compared to UDCA monotherapy. Baseline IgG and ALP are the most significant predictors of fibrosis regression. The new predictive score, FRS, incorporating baseline IgG and ALP, can effectively identify individuals who would benefit from the combination therapy.

Add-on immunosuppressive therapy may benefit selected patients with primary biliary cholangitis and autoimmune phenomena

Background

Mildly elevated levels of transaminase and/or immunoglobulin G (IgG) are common in patients with primary biliary cholangitis (PBC). It is still unclear whether adding immunosuppressive therapy to ursodeoxycholic acid (UDCA) benefits those patients who are not fulfilling the diagnostic criteria of PBC with autoimmune hepatitis (AIH) features.

Objectives

To assess the efficacy of adding immunosuppressive therapy to UDCA for patients with PBC and autoimmune phenomena but not fulfilling the diagnostic criteria of PBC with AIH features.

Design

This is a retrospective-prospective cohort study in a tertiary medical center.

Methods

Patients with PBC and autoimmune phenomena were defined by the elevation of IgG and/or transaminase but did not fulfill the diagnostic criteria of PBC with AIH features. We grouped these patients based on with and without add-on immunosuppressive therapy and balanced their baseline characteristics using inverse probability treatment weighting (IPTW).

Results

A total of 652 patients with PBC and autoimmune phenomena were included, with a median follow-up of 4.08 years. After IPTW, the pseudo sample size in the add-on therapy and monotherapy groups was 558 and 655, respectively. After 1 year of observation, patients in the add-on therapy group had a higher biochemical response rate (normalization of transaminase and IgG levels) (49% versus 17%, p < 0.001). Furthermore, add-on therapy improved the transplant-free survival in the subgroup of patients with PBC and transaminase ⩾3 × upper limit of normal (ULN) or IgG ⩾1.3 × ULN (p = 0.033).

Conclusion

Add-on immunosuppressive therapy may improve the normalization rates of transaminase and IgG levels in all patients with PBC and mildly elevated transaminase and IgG levels and the long-term outcomes in the subgroup of the patients with transaminase ⩾3 × ULN or IgG ⩾1.3 × ULN.

Guidelines on the Diagnosis and Management of Primary Biliary Cholangitis (2021)

In 2015, the Chinese Society of Hepatology and the Chinese Society of Gastroenterology published a consensus on primary biliary cholangitis (PBC). In the past years, numerous clinical studies have been published in the field of PBC. To guide the clinical diagnosis and management of PBC patients, the Chinese Society of Hepatology invited a panel of experts to assess the new clinical evidence and formulate the current guidelines.

The Inconvenient Truth of Primary Biliary Cholangitis/Autoimmune Hepatitis Overlap Syndrome

The term 'PBC/AIH-overlap' has been applied when features of autoimmune hepatitis (AIH), be they biochemical, serological or histological, coexist with primary biliary cholangitis (PBC), either at first presentation or sequentially during disease course. Several treatment paradigms have been proposed, extrapolated from those of the primary conditions. However, there are no randomised studies showing improved survival with combination therapy compared to bile acid monotherapy. In the absence of high-quality evidence, multidisciplinary patient-specific approaches must be used to individualise treatment pathways, with appreciation that disease phenotypes are not always static, differ in treatment responses, and have the potential to evolve over time.

Epidemiology and surveillance of autoimmune hepatitis in Asia

Autoimmune hepatitis (AIH) is a chronic inflammatory liver disease that mainly injures the hepatocytes. The autoimmune disease might be involved in its aetiology, but this remains to be confirmed. Recently epidemiological studies of AIH in Asia have been broadly conducted, revealing characteristics and management of AIH patients in Asia. In East Asia, most AIH patients are type 1, and type 2 AIH is very rare. However, type 2 AIH in South Asia is as frequent as in Europe and the USA. HLA-DR4 is associated with the characteristics of type 1 AIH in East Asia, whereas HLA-DR3 occurs in AIH patients from South Asia. AIH prevalence worldwide is increasing, and several studies have reported a prevalence of 19.44, 22.80 and 12.99 per 100 000 people in Europe, the USA and Asia respectively. A meta-analysis of studies on AIH showed similar annual incidence rates for all regions, with 1.31, 1.37 and 1.00 per 100 000 people in Asia, Europe and the USA respectively. The increase in the rates could be attributable to the increased awareness of disease concepts and diagnosis. In South Asia, most cases were diagnosed as AIH only after having progressed to cirrhosis, which may cause a higher mortality rate in South Asia than in East Asia. Therefore, the early diagnosis and treatment of AIH patients can improve the current situation in Asia.

The Spectrum of Autoimmune Liver Disorders, Clinical Presentation, and Autoantibodies in Patients From a Tertiary Care Center in Pakistan

Background The autoimmune illnesses that affect the liver include autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC), and overlap syndrome. In our patients, we aimed to address the complete spectrum of autoimmune liver disorders, clinical presentation, and autoantibodies. Methods The study included all the patients diagnosed with autoimmune liver disorder irrespective of age, gender, and ethnic background presented at the liver clinic of the hospital in the last two years. The diagnosis was based on characteristic clinical and laboratory findings, the presence of one or more characteristic autoantibodies, and/or histological abnormalities. The diagnosis of AIH was further validated by revised International AIH Group criteria using a scoring calculator. The diagnostic criteria for PBC required the presence of chronic elevation of alkaline phosphatase (ALP) with positive antimitochondrial antibody (AMA) or positive PBC-specific anti-nuclear antibodies (ANA) (sp-100, gp-210) tests and/or compatible histology. The patients of AIH-PBC overlap syndrome fulfilled the criteria for AIH in the setting of PBC. Patients having liver involvement in other autoimmune disorders were included in the study. Results The total number of patients was 124; 83 (67%) were females; mean age ± standard error of mean (SEM) was 44.97 ± 1.47 years with a range of 09-84 years. Type-1 AIH was seen in 68 (54.8%) patients, type-2 AIH in 10 (8.1%) patients, PBC in 22 (17.7%) patients, overlap of PBC with AIH in 10 (8.1%) patients, IgG4 disease in four (3.2%) patients, psoriasis-specific immune hepatitis in four (3.2%) patients, celiac disease-related hepatitis in three (2.4%) patients, sarcoidosis in two (1.6%) patients, and ichthyosis-associated hepatitis in one (0.8%) patient. There was a high prevalence of cirrhosis (50%) at the time of presentation; 19% of patients had decompensated liver disease. ANA was positive in 52/68 cases of AIH type-1, but anti-smooth muscle antibody (ASMA) was reactive only in nine cases and anti-soluble liver antigen (SLA) in five cases. There was no female preponderance in type-2 AIH (M:F = 6:4). AMA was reactive in 25 (78%) cases of PBC and overlap syndrome. Antibodies prevalent in PBC (AMA-M2, AMA-M2-3E, sp-100, gp-210, anti-Ro52) were also seen in some cases of AIH, though they did not fulfill the criteria of the overlap syndrome. Conclusion There is an unmet need for the early diagnosis of autoimmune liver diseases and the initiation of appropriate management to prevent complications.

Autoimmune biliary diseases: primary biliary cholangitis and primary sclerosing cholangitis

Autoimmune cholestatic liver diseases are rare hepato-biliary disorders characterized by a progressive, inflammatory destruction of bile ducts. Primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) are the main autoimmune cholestatic liver diseases. Both may evolve into secondary biliary cirrhosis and its complications. Therapeutic options are limited and liver transplantation remains the only definitive treatment for PBC and PSC.

Most PBC and PSC patients have a typical presentation, which does not require liver biopsy. However, in routine clinical practice, important variants or specific subgroups that benefit from liver biopsy for proper management may be observed. Herein, we provide a general overview of clinical and pathological characteristic of PBC and PSC, highlighting the most important features for routine diagnostic practice.

Cholestatic liver disease: Practice guidelines from the Saudi Association for the Study of Liver diseases and Transplantation

Cholestatic liver diseases (CLDs) are a group of diseases characterized by jaundice and cholestasis as the main presentation with different complications, which have considerable impact on the liver and can lead to end-stage liver disease, cirrhosis, and liver-related complications. In the last few years, tremendous progress has been made in understanding the pathophysiology, diagnosis, and treatment of patients with these conditions. However, several aspects related to the management of CLDs remain deficient and unclear. Due to the lack of recommendations that can help in the management, treatment of those conditions, the Saudi Association for the Study of Liver diseases and Transplantation (SASLT) has created a task force group to develop guidelines related to CLDs management in order to provide a standard of care for patients in need. These guidelines provide general guidance for health care professionals to optimize medical care for patients with CLDs for both adult and pediatric populations, in association with clinical judgments to be considered on a case-by-case basis. These guidelines describe common CLDs in Saudi Arabia, with recommendations on the best approach for diagnosis and management of different diseases based on the Grading of Recommendation Assessment (GRADE), combined with a level of evidence available in the literature.

Worse Response to Ursodeoxycholic Acid in Primary Biliary Cholangitis Patients with Autoimmune Hepatitis Features

BACKGROUND

There is limited evidence on the treatment response of primary biliary cholangitis (PBC) with autoimmune hepatitis (AIH) features but not meet the criteria of PBC-AIH syndromes. The aim of this study was to elucidate the clinical characteristics of PBC patients with features of AIH.

METHODS

We included patients with diagnostic criteria of PBC. All patients were treated with ursodeoxycholic acid (UDCA) and without immunosuppressive agents for >1 year. The biochemical response was evaluated at 1 year after the treatment of UDCA.

RESULTS

Among 432 patients with PBC, 166 (38.4%) patients did not achieve biochemical response within 1 year of UDCA treatment. Nonresponders had a lower albumin level and higher immunoglobulin G, alanine transaminase (ALT), alanine aminotransferase (AST), alkaline phosphatase, glutamyl transpeptidase and total bilirubin levels (p < 0.05). The response rates were significantly lower in patients with elevated level of IgG or ALT or AST. Moreover, the higher the IgG or AST level was, the lower the response rate was in patients with PBC, regardless of cirrhosis. For patients with cirrhosis, there was no differences among patients with different levels of ALT. Patients in the PBC with AIH features group had a significant lower response rate than patients in the PBC-only group. Among the 139 patients who underwent liver biopsy, 54 were nonresponsive to UDCA and 48 (88.9%) shown mild interface hepatitis.

CONCLUSION

In conclusion, PBC patients with AIH features had a worse response to UDCA therapy.

The challenges of primary biliary cholangitis: What is new and what needs to be done

Primary Biliary Cholangitis (PBC) is an uncommon, chronic, cholangiopathy of autoimmune origin and unknown etiology characterized by positive anti-mitochondrial autoantibodies (AMA), female preponderance and progression to cirrhosis if left untreated. The diagnosis is based on AMA- or PBC-specific anti-nuclear antibody (ANA)-positivity in the presence of a cholestatic biochemical profile, histologic confirmation being mandatory only in seronegative cases. First-line treatment is ursodeoxycholic acid (UDCA), which is effective in preventing disease progression in about two thirds of the patients. The only approved second-line treatment is obeticholic acid. This article summarizes the most relevant conclusions of a meeting held in Lugano, Switzerland, from September 23rd-25th 2018, gathering basic and clinical scientists with various background from around the world to discuss the latest advances in PBC research. The meeting was dedicated to Ian Mackay, pioneer in the field of autoimmune liver diseases. The role of liver histology needs to be reconsidered: liver pathology consistent with PBC in AMA-positive individuals without biochemical cholestasis is increasingly reported, raising the question as to whether biochemical cholestasis is a reliable disease marker for both clinical practice and trials. The urgent need for new biomarkers, including more accurate markers of cholestasis, was also widely discussed during the meeting. Moreover, new insights in interactions of bile acids with biliary epithelia in PBC provide solid evidence of a role for impaired epithelial protection against potentially toxic hydrophobic bile acids, raising the fundamental question as to whether this bile acid-induced epithelial damage is the cause or the consequence of the autoimmune attack to the biliary epithelium. Strategies are needed to identify difficult-to-treat patients at an early disease stage, when new therapeutic approaches targeting immunologic pathways, in addition to bile acid-based therapies, may be effective. In conclusion, using interdisciplinary approaches, groundbreaking advances can be expected before long in respect to our understanding of the etiopathogenesis of PBC, with the ultimate aim of improving its treatment.

CTHRC1 expression in primary biliary cholangitis

OBJECTIVES

Collagen triple helix repeat containing-1 (CTHRC1) is a highly conserved extracellular matrix glycoprotein that is overexpressed in two murine models of cholestatic liver fibrosis. Elevated CTHRC1 has been found to attenuate liver fibrosis in these murine models, thus we aimed to study the expression of CTHRC1 in patients with cholestatic liver diseases and its correlation with hepatic conditions.

METHODS

Ninety patients with chronic liver disease, including 48 had primary biliary cholangitis (PBC), 18 had primary sclerosing cholangitis (PSC) and 24 had chronic hepatitis B (CHB), together with five healthy controls (HC), were recruited to this study. Participants' liver sections were analyzed using immunohistochemistry. Serum CTHRC1 levels in another cohort of 59 patients with PBC and 10 age-matched HC were detected by enzyme-linked immunosorbent assay.

RESULTS

CTHRC1 protein was primarily expressed in activated hepatic stellate cells (HSC). CTHRC1 expression was significantly increased in the PBC and PSC groups, compared with the HC and CHB groups. Importantly, the hepatic fibrosis stage of the PBC group was positively correlated with hepatic CTHRC1 expression (r = 0.425, P = 0.003). Meanwhile, there were significant correlations between serum CTHRC1 levels and both the degrees of hepatic inflammation and fibrosis stage in the PBC group (r = 0.300, P = 0.022; r = 0.321, P = 0.012).

CONCLUSION

CTHRC1 may play a role in hepatic fibrogenesis in PBC and that serum CTHRC1 may be a potential novel noninvasive biomarker in the assessment of liver fibrosis and inflammation.

Variant and Specific Forms of Autoimmune Cholestatic Liver Diseases

Primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) are the main autoimmune cholestatic liver diseases. IgG4-associated sclerosing cholangitis is another distinct immune-mediated cholestatic disorder of unknown aetiology that is frequently associated with autoimmune pancreatitis or other IgG4-related diseases. Although the majority of PBC and PSC patients have a typical presentation, there are common and uncommon important variants or specific subgroups that observed in everyday routine clinical practice. In this updated review, we summarize the published data giving also our own experience on the variants and specific groups of autoimmune cholestatic liver diseases. Actually, we give in detail the underlining difficulties and the rising dilemmas concerning the diagnosis and management of these special conditions in the clinical spectrum of autoimmune cholestatic liver diseases including the IgG4-associated sclerosing cholangitis highlighting also the uncertainties and the potential new eras of the research agenda.

Overlap Syndrome of Autoimmune Hepatitis and Primary Biliary Cholangitis

Overlap syndrome of autoimmune hepatitis (AIH) and primary biliary cholangitis (PBC) is typically defined as concomitant or serial presentation with clinical features of both of these 2 distinct diseases. The Paris criteria and variations of the International Autoimmune Hepatitis group scoring systems for the diagnosis of AIH have been used to diagnose overlap syndrome. If left untreated, patients with overlap syndrome will have higher rates of portal hypertension, gastrointestinal bleeding, ascites, death, and need for liver transplant. Therefore, early identification is essential in providing appropriate therapy to potentially prevent long-term adverse outcomes in patients with overlap syndrome.

Autoimmune Hepatitis in the Asia-Pacific Area

Autoimmune hepatitis has been considered as a relatively rare immunological liver disease, especially in the Asia-Pacific area. Although the diagnosis criteria and immunosuppressive treatment regimens have been established, there are still some challenges. According to the different presentations, the personalized management of patients who suffer from this disease, including those with chronic or acute severe onset, the autoantibody-negative phenotype and cirrhosis are necessarily descriptive. Each subgroup of patients should receive an individualized therapy. Here, we review the recent studies of autoimmune hepatitis, mainly focusing on the epidemiology and genetics, personalized diagnostics, individualized treatment strategies, special subgroups and outcomes. Most of the research in the literature is based on Japanese and Chinese populations.

Performance of transient elastography in assessing liver fibrosis in patients with autoimmune hepatitis-primary biliary cholangitis overlap syndrome

AIM

To investigate the performance of transient elastography (TE) for diagnosis of fibrosis in patients with autoimmune hepatitis-primary biliary cholangitis (AIH-PBC) overlap syndrome.

METHODS

A total of 70 patients with biopsy-proven AIH-PBC overlap syndrome were included. Spearman correlation test was used to analyze the correlation of liver stiffness measurement (LSM) and fibrosis stage. Independent samples Student’s t-test or one-way analysis of variance was used to compare quantitative variables. Receiver operating characteristics (ROC) curve was used to calculate the optimal cut-off values of LSM for predicting individual fibrosis stages. A comparison on the diagnostic accuracy for severe fibrosis was made between LSM and other serological scores.

RESULTS

Patients with AIH-PBC overlap syndrome had higher median LSM than healthy controls (11.3 ± 6.4 kPa vs 4.3 ± 1.4 kPa, P < 0.01). LSM was significantly correlated with fibrosis stage (r = 0.756, P < 0.01). LSM values increased gradually with an increased fibrosis stage. The areas under the ROC curves of LSM for stages F ≥ 2, F ≥ 3, and F4 were 0.837 (95%CI: 0.729-0.914), 0.910 (0.817-0.965), and 0.966 (0.893-0.995), respectively. The optimal cut-off values of LSM for fibrosis stages F ≥ 2, F ≥ 3, and F4 were 6.55, 10.50, and 14.45 kPa, respectively. LSM was significantly superior to fibrosis-4, glutaglumyl-transferase/platelet ratio, and aspartate aminotransferase-to-platelet ratio index scores in detecting severe fibrosis (F ≥ 3) (0.910 vs 0.715, P < 0.01; 0.910 vs 0.649, P < 0.01; 0.910 vs 0.616, P < 0.01, respectively).

CONCLUSION

TE can accurately detect hepatic fibrosis as a non-invasive method in patients with AIH-PBC overlap syndrome.

EASL Clinical Practice Guidelines: The diagnosis and management of patients with primary biliary cholangitis

Primary biliary cholangitis (PBC) is a chronic inflammatory autoimmune cholestatic liver disease, which when untreated will culminate in end-stage biliary cirrhosis. Diagnosis is usually based on the presence of serum liver tests indicative of a cholestatic hepatitis in association with circulating antimitochondrial antibodies. Patient presentation and course can be diverse and risk stratification is important to ensure all patients receive a personalised approach to their care. The goals of treatment and management are the prevention of end-stage liver disease, and the amelioration of associated symptoms. Pharmacologic approaches in practice, to reduce the impact of the progressive nature of disease, currently include licensed therapies (ursodeoxycholic acid and obeticholic acid) and off-label therapies (fibric acid derivatives, budesonide). These clinical practice guidelines summarise the evidence for the importance of a structured, life-long and individualised, approach to the care of patients with PBC, providing a framework to help clinicians diagnose and effectively manage patients.

Similarities and Differences in Autoimmune Hepatitis Epidemiology between East and West: Autoimmune Hepatitis in East Asia, Southeast Asia, and South Asia

Background

Autoimmune hepatitis (AIH) is a relatively rare disease that can develop regardless of age or ethnicity. However, its clinical features differ between eastern and western populations due to several heterogeneous genetic and environmental factors. We herein report the clinical characteristics of AIH patients in East Asia, Southeast Asia, and South Asia.

Summary and Key Messages

The prevalence of AIH in eastern countries is considered to be lower than in western countries. Although a few young patients with type 2 AIH have been observed in South Asia, most patients in Asia are middle-aged women with type 1 AIH who respond well to steroid-based immunosuppressive therapy. Human leukocyte antigen DR4 is suggested to be an influential factor in the genetic background of AIH patients in Asia, particularly in East Asia. Notably, AIH may be induced by some societal- or culture-associated medicines, including herbal medicines. The IAIHG (International Autoimmune Hepatitis Group) scoring systems are generally accepted as the standard diagnostic methods for AIH in Asian countries. The results of repeated nationwide surveys in Japan suggest that the clinical features of AIH patients in East Asia are changing, with IgG levels and rates of anti-nuclear antibody positivity decreasing.

The Natural History and Prognosis of Primary Biliary Cirrhosis with Clinical Features of Autoimmune Hepatitis

Although a variant of primary biliary cirrhosis (PBC) characterized by features of autoimmune hepatitis (AIH) has been recognized for many years, few studies with ample numbers of patients have focused on its natural history. This study aimed to clarify the natural history, prognosis, and response to therapy in a cohort of patients with PBC with AIH features. We retrospectively analyzed 277 PBC patients without AIH features and 46 PBC patients with AIH features seen between September 2004 and April 2014. The 5-year adverse outcome-free survival of PBC patients with AIH features was 58% compared to 81% in PBC patients without AIH features. Multivariate analysis in the patients with AIH features indicated that total bilirubin ≥ 2.70× the upper limit of normal predicted a poor prognosis (p = 0.008, relative risk 8.39, 95% confidence interval (CI) 1.73, 40.73). Combination therapy with ursodeoxycholic acid (UDCA) and immunosuppression provided better short-term responses in PBC patients with AIH features, defined by multiple criteria. Higher aspartate aminotransferase (AST) level at accession suggested better prognosis for PBC patients with AIH features while worse prognosis for PBC patients without AIH features. PBC patients with AIH features differ from those without AIH features in terms of natural history, prognostic indicators, and response to therapy.

Unmet challenges in immune-mediated hepatobiliary diseases

It is ironic that the liver, which serves a critical function in immune tolerance, itself becomes the victim of an autoimmune attack. Indeed, liver autoimmunity and the autoimmune diseases associated with both innate and adaptive responses to hepatocytes and/or cholangiocytes are models of human autoimmunity. For example, in primary biliary cirrhosis, there exists a well-defined and characteristic autoantibody and considerable homogeneity between patients. In autoimmune hepatitis, there are clinical characteristics that allow a rigorous subset definition and well-defined inflammatory infiltrates. In both cases, there are defects in a variety of immune pathways and including regulatory cells. In primary sclerosing cholangitis, with its characteristic overlap with inflammatory bowel disease, there are unique defects in innate immunity and particular important contribution of lymphoid homing to disease pathogenesis. In these diseases, as with other human autoimmune processes, there is the critical understanding that pathogenesis requires a genetic background, but is determined by environmental features, and indeed the concordance of these diseases in identical twins highlights the stochastic nature of immunopathology. Unfortunately, despite major advances in basic immunology and in immunopathology in these diseases, there remains a major void in therapy. The newer biologics that are so widely used in rheumatology, neurology, and gastroenterology have not yet seen success in autoimmune liver disease. Future efforts will depend on more rigorous molecular biology and systems analysis in order for successful application to be made to patients.

Extrahepatic autoimmune conditions associated with primary biliary cirrhosis

There is a paucity of information on extrahepatic autoimmune (EHA) conditions associated with primary biliary cirrhosis (PBC) and on the impact of EHA conditions on PBC patients' survival. Our goal was to assess the association between PBC and other autoimmune diseases and the impact of EHA conditions on the natural history of PBC. We took advantage of 361 consecutive PBC patients enrolled between 1975 and 2012 (22 males, 339 females; mean follow-up 8 ± 6.9 years). Any associated EHA conditions, PBC histological stage at diagnosis, biochemical data, physiological history, and extrahepatic malignancies developing during the follow-up were recorded. Survival was analyzed by means of Kaplan-Meier curves. Importantly, 221 patients (61.2 %) had at least one EHA conditions: 45 patients (20.4 %) had Hashimoto thyroiditis; 7 (3.2 %) had Graves' thyroiditis; 65 (29.4 %) had Raynaud's phenomenon; 124 (56.1 %) had Sjogren's syndrome; 8 (3.6 %) had systemic lupus erythematosus; 22 (9.9 %) had scleroderma; 22 (9.9 %) had rheumatoid arthritis; 18 (8.1 %) had cutaneous autoimmune diseases; 8 (3.6 %) had vasculitis; 5 (1.4 %) had celiac disease; and 25 (13.1 %) had other EHA conditions. The proportion of patients with associated EHA conditions enrolled during representative periods (1975-1980, 1981-1990, 1991-2000, 2001-2010, 2011-2012) remained stable. No differences emerged between patients with versus without EHA conditions in terms of mean age at PBC diagnosis, antimitochondrial antibody (AMA), or antinuclear antibody (ANA) positivity, histological stage at diagnosis, smoking habits, alcohol consumption, or BMI >25. Multiple logistic regression analysis showed that only female gender was significantly associated with positivity for EHA conditions (OR 4.8; 95 % CI 1.6-13.7, p = 0.004). The mean survival after the diagnosis of PBC was much the same in patients with and without EHA conditions. In conclusion, EHA conditions are often associated with PBC, especially in female patients, but they do not reduce patient survival.

The coexistence of Sjögren's syndrome and primary biliary cirrhosis: a comprehensive review

Organ-specific and systemic autoimmune diseases share numerous features and often coexist in the same patient. Autoimmune cholangitis/primary biliary cirrhosis and Sjogren syndrome represent paradigmatic examples of the common grounds of different autoimmunity phenotypes based on similarities in clinical manifestations and immunopathogenesis. In fact, primary biliary cirrhosis and Sjogren's syndrome have both been coined as an autoimmune epithelitis in which apoptosis may be in both cases the key element to explain the organ-specific immune-mediated injury against the biliary and exocrine gland epithelia, respectively. Further, growing evidence supports in both diseases the view that B cells, T cytotoxic cells, and T helper cells are involved in chronic inflammation, likely via the altered expression of pro-inflammatory cytokines. The presence of estrogen receptors on the biliary and exocrine gland epithelia has been advocated as a key to the female predominance encountered in primary biliary cirrhosis and Sjogren's syndrome. Sadly, despite available data, therapeutic approaches remain largely unsatisfactory and recent studies with mechanistic approaches (as in the case of B cell depletion with rituximab) have been of partial benefit only. Future studies should focus on new molecular tools (single-cell transcriptomics, microRNA, epigenetics) to provide unique insights into common mechanisms.

Animal models of primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is characterized histologically by the presence of chronic non-suppurative destructive cholangitis of the small interlobular bile duct, leading to chronic progressive cholestasis. Most PBC patients are asymptomatic and have a reasonable prognosis, but a few develop esophageal varices or jaundice, rapidly leading to liver failure within a short period. As multiple factors appear to be involved in the onset of PBC, its clinical course may be complicated. Therefore, the use of an animal model would be valuable for clarifying the pathogenesis of PBC. Here, we review recent data of selected PBC models, particularly spontaneous models, xenobiotic immunized models, and infection-triggered models. There are a number of spontaneous models: the NOD.c3c4, dominant-negative TGF-β receptor II, IL-2Rα-/-, Scurfy, and Ae2a,b-/- mice. These animal models manifest distinct clinical and immunological features similar, but also often different, from those of human PBC. It is clear that a combination of genetic predisposition, environmental factors, and immunological dysfunction contribute to the pathogenesis of PBC. The diverse clinical course and complexity of the immunological mechanisms of PBC cannot be fully recapitulated solely any single animal model. The challenge remains to develop a progressive PBC disease model that exhibits fibrosis, and ultimately hepatic failure.

The clinical phenotypes of autoimmune hepatitis: A comprehensive review

Autoimmune hepatitis (AIH) fulfills the generally accepted contemporary criteria of an autoimmune liver disease: the presence of autoantibodies and autoreactive T cells, a female gender bias, association with other autoimmune diseases, response to immunosuppressive therapy and strong associations with the major histocompatibility complex HLA loci. It occurs worldwide in both children and adults and is marked by both etiopathogenic and clinical heterogeneity, differing from the other putative autoimmune liver diseases, primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC), albeit occasionally presenting with overlapping features of PBC or PSC. Although diagnostic criteria have been established and validated, there are still major issues to be clarified due to its variability, such as autoantibody-negative AIH, drug-induced AIH, AIH sharing features with PBC or PSC, and post-transplant de novo AIH. In view of the diverse presentations and courses, including classical chronic onset, acute and acute severe onset, cirrhosis and decompensated cirrhosis, individualized management of patients is indicated. Each patient should receive a personalized analysis of the benefits and side effect risks of drugs. Herein we describe a comprehensive review of the clinical phenotypes of AIH underscoring its clinical heterogeneity.

Vitamin D in primary biliary cirrhosis, a plausible marker of advanced disease

Vitamin D immune-modulating effects were extensively studied, and low levels have been linked with autoimmune diseases. The associations of vitamin D with autoimmune diseases of the liver, and particularly primary biliary cirrhosis (PBC), are yet to be defined. Hence, in this study, serum levels of vitamin D were determined in 79 patients with PBC and 70 age- and sex-matched controls by the LIAISON chemiluminescent immunoassays (DiaSorin-Italy). Clinical and serological parameters of patients were analyzed with respect to vitamin D status. Mean levels of vitamin D were significantly lower among patients with PBC compared with controls (16.8 ± 9 vs. 22.1 ± 9 ng/ml; p = 0.029), and vitamin D deficiency (≤10 ng/ml) was documented in 33% of patients with PBC versus 7% of controls (p < 0.0001). Vitamin D levels inversely correlated with advanced liver damage and the presence of concomitant autoimmune diseases. In contrast, higher levels of vitamin D were observed among patients with PBC treated with ursodeoxycholic acid (UDCA). In conclusion, low vitamin D levels are common among patients with PBC and correlate with advanced disease, lack of UDCA therapy and autoimmune comorbidity. This alludes to the plausible roles of vitamin D as a prognostic marker of PBC severity, and as a potential player in this disease pathogenesis. While further studies are awaited, monitoring vitamin D in patients with PBC and use of supplements may be advisable.

Silicone implants and lymphoma: The role of inflammation

The risk of hematological malignancies is mainly determined by genetic background, age, sex, race and ethnicity, geographic location, exposure to certain chemicals and radiation; along with the more recently proposed immune factors such as chronic inflammation, immunodeficiencies, autoimmunity, and infections. Paradigmatic examples include the development of lymphoma in Sjögren's syndrome and Hashimoto thyroiditis, gastric MALT lymphoma in Helicobacter pylori infection, or lymphomas associated with infections by Epstein-Barr virus, human herpes virus 8 (HHV 8) and leukemia/lymphoma virus 1 (HTLV-1). A growing number of reports indicates an increased risk of lymphoma, particularly of the anaplastic large cell (ALCL) type. The implants, specifically those used in the past, elicit chronic stimulation of the immune system against the prosthetic material. This is particularly the case in genetically susceptible hosts. We suggest that polyclonal activation may result in monoclonality in those at risk hosts, ultimately leading to lymphoma. We suggest that patients with an inflammatory response against silicone implants be monitored carefully.

Autoimmunity in 2013

The peer-reviewed publications in the field of autoimmunity published in 2013 represented a significant proportion of immunology articles and grew since the previous year to indicate that more immune-mediated phenomena may recognize an autoimmune mechanism and illustrated by osteoarthritis and atherosclerosis. As a result, our understanding of the mechanisms of autoimmunity is becoming the paradigm for translational research in which the progress in disease pathogenesis for both tolerance breakdown and inflammation perpetuation is rapidly followed by new treatment approaches and clinical management changes. The similarities across the autoimmune disease spectrum outnumber differences, particularly when treatments are compared. Indeed, the therapeutics of autoimmune diseases are based on a growing armamentarium that currently includes monoclonal antibodies and small molecules which act by targeting molecular markers or intracellular mediators with high specificity. Among the over 100 conditions considered as autoimmune, the common grounds are well illustrated by the data reported for systemic lupus erythematosus and rheumatoid arthritis or by the plethora of studies on Th17 cells and biomarkers, particularly serum autoantibodies. Further, we are particularly intrigued by studies on the genomics, epigenetics, and microRNA at different stages of disease development or on the safe and effective use of abatacept acting on the costimulation of T and B cells in rheumatoid arthritis. We are convinced that the data published in 2013 represent a promising background for future developments that will exponentially impact the work of laboratory and clinical scientists over the next years.

Unique topics and issues in rheumatology and clinical immunology

Clinicians are facing unexpected issues in everyday practice, and these may become counterintuitive or challenging. Illustrative examples are provided by the hypersensitivity to universally used immunosuppressants such as corticosteroids or antibiotics such as beta-lactam. Secondly, additional issues are represented by the discovery of new pathogenetic mechanisms involved in rheumatoid and psoriatic arthritis or other chronic inflammatory diseases, genomic susceptibility to enigmatic diseases such as giant cell arteritis, or the shared role of specific mediators such as semaphorins. Third, the therapeutic armamentarium has dramatically changed over the past decade following the introduction of biotechnological drugs, and new mechanisms are being proposed to reduce adverse events or increase the drug effectiveness, particularly on cardiovascular comorbidities. Finally, rare diseases continue to represent difficult cases, as for Cogan's syndrome, with limited literature available for clinical recommendations. For these reason, the present issue of Clinical Reviews in Allergy and Immunology is timely and dedicated to these and other unique topics in clinical immunology and allergy. The aim of this issue is thus to help clinicians involved in internal medicine as well as allergists and clinical immunologists while discussing new pathways that will prove important in the near future.

Autoimmune hepatitis: East meets west

Autoimmune hepatitis (AIH) is an inflammatory liver disease with diverse clinical spectrum, which predominantly affects females. This review provides detailed comparisons of epidemiology, genetic predispositions, clinical features, risk factors of hepatocellular carcinoma, and mortality in AIH patients between eastern and western countries. AIH prevalence and incidence are lower in Asia-Pacific area than in Europe and America. European and American patients seem to have more severe disease, characterized with human leukocyte antigen-DR3 haplotype, younger age, more AIH-induced "cirrhosis" at diagnosis, higher elevated serum immunoglobulin G levels, and positive rate of antisoluble liver antigen/liver pancreatitis. The overall AIH diagnostic accuracy of revised original criteria and simplified scoring system are similar in European/American populations and Asian. Cirrhosis at presentation and non-response to immunosuppressive therapy within 1 year are the most important predictors for poor prognosis of AIH patients.

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

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

Primary biliary cirrhosis: Clinical and laboratory criteria for its diagnosis

Primary biliary cirrhosis (PBC) is a chronic progressive cholestatic granulomatous, and destructive inflammatory lesion of small intralobular and septal bile ducts, which is likely to be caused by an autoimmune mechanism with a the presence of serum antimitochondrial antibodies and a potential tendency to progress to cirrhosis. Despite the fact that the etiology of this disease has been unknown so far, there has been a considerable body of scientific evidence that can reveal the clinical and laboratory signs of PBC and the individual components of its pathogenesis and elaborate diagnostic criteria for the disease and its symptomatic therapy. Deficiencies in autoimmune tolerance are critical factors for the initiation and perpetuation of the disease. The purpose of this review is to summarize the data available in the literature and the author’s findings on clinical and laboratory criteria for the diagnosis of PBC. This review describes the major clinical manifestations of the disease and the mechanisms of its development. It presents the immunological, biochemical, and morphological signs of PBC and their significance for its diagnosis. A great deal of novel scientific evidence for the problem of PBC has been accumulated. However, the inadequate efficiency of therapy for the disease lends impetus to the quest for its etiological factors and to further investigations of its pathogenetic mechanisms and, on this basis, to searches for new methods for its early diagnosis.

Retrospective analysis of autoimmune hepatitis-primary biliary cirrhosis overlap syndrome in Korea: characteristics, treatments, and outcomes

Background/Aims

Overlap syndrome of autoimmune hepatitis (AIH) and primary biliary cirrhosis (PBC) (AIH-PBC overlap syndrome) is a rare disease that has not been clearly characterized in Korean patients. This study investigated the clinical features of AIH-PBC overlap syndrome compared with those of AIH and PBC alone.

Methods

This retrospective cohort study included 158 consecutive patients who were diagnosed as AIH (n=61), PBC (n=81), or AIH-PBC overlap syndrome (n=9) based on the Paris and the International Autoimmune Hepatitis Group (IAIHG) criteria from 2001 to 2011 in Korea. We compared the clinical features of these three groups retrospectively, including their biochemical characteristics, treatments, responses, and clinical outcomes.

Results

The AIH-PBC overlap syndrome patients exhibited biochemical characteristics of both AIH and PBC, and showed a similar response to ursodeoxycholic acid (UDCA) monotherapy as for the PBC patients. However, the response of AIH-PBC overlap syndrome patients to UDCA and steroid combination therapy was worse than the response of AIH patients to steroid-based therapy (P=0.024). Liver cirrhosis developed more rapidly in AIH-PBC overlap syndrome patients than in AIH patients group (P=0.013), but there was no difference between AIH-PBC overlap syndrome patients and PBC patients. The rates of developing hepatic decompensation did not differ significantly between the groups.

Conclusions

The AIH-PBC overlap syndrome patients exhibited a worse response to UDCA and steroid combination therapy and a faster cirrhotic progression compared with AIH patients.

Ongoing activation of autoantigen-specific B cells in primary biliary cirrhosis

The serologic hallmark of primary biliary cirrhosis (PBC), the antimitochondrial response to the E2 component of the pyruvate dehydrogenase complex (PDC-E2), has unique features, including continuous high titers of immunoglobulin M (IgM) and IgG reactivity throughout all stages of disease, capable not only of target enzyme inhibition, but also crossreactive with chemical xenobiotics that share molecular homology with the inner lipoyl domain of PDC-E2; such chemicals have been proposed as potential etiological agents. We used flow cytometry and enzyme-linked immunospot assay (ELISPOT) to examine B-cell subsets in 59 subjects, including 28 with PBC, 13 with primary sclerosing cholangitis (PSC), and 18 healthy controls. Strikingly, in PBC, although there were no significant differences in B-cell phenotype subpopulations, 10% of the total IgG and IgA plasmablast population and 23% of the IgM plasmablast population were uniquely reactive with PDC-E2, detected in the CXCR7+ CCR10low plasmablast population. In contrast, plasmablast reactivity to a control antigen, tetanus toxoid, was minimal and similar in all groups. Additionally, we isolated plasmablast-derived polyclonal antibodies and compared reactivity with plasma-derived antibodies and noted a distinct noncirculating tissue source of xenobiotic crossreacting antibodies. The high levels of autoantigen specific peripheral plasmablasts indicate recent activation of naive or memory B cells and a continuous and robust activation. The presence of CXCR7+ CCR10low PDC-E2-specific ASCs suggests a mechanistic basis for the migration of circulating antigen specific plasmablasts to the mucosal epithelial ligands CXCL12 and CCL28.

CONCLUSION

Our findings suggest a sustained rigorous B-cell response in PBC, likely activated and perpetuated by cognate autoantigen.

Myasthenia Gravis: paradox versus paradigm in autoimmunity

Myasthenia Gravis (MG) is a paradigm of organ-specific autoimmune disease (AID). It is mediated by antibodies that target the neuromuscular junction. The purpose of this review is to place MG in the general context of autoimmunity, to summarize the common mechanisms between MG and other AIDs, and to describe the specific mechanisms of MG. We have chosen the most common organ-specific AIDs to compare with MG: type 1 diabetes mellitus (T1DM), autoimmune thyroid diseases (AITD), multiple sclerosis (MS), some systemic AIDs (systemic lupus erythematous (SLE), rheumatoid arthritis (RA), Sjogren's syndrome (SS)), as well as inflammatory diseases of the gut and liver (celiac disease (CeD), Crohn's disease (CD), and primary biliary cirrhosis (PBC)). Several features are similar between all AIDs, suggesting that common pathogenic mechanisms lead to their development. In this review, we address the predisposing factors (genetic, epigenetic, hormones, vitamin D, microbiota), the triggering components (infections, drugs) and their interactions with the immune system [1,2]. The dysregulation of the immune system is detailed and includes the role of B cells, Treg cells, Th17 and cytokines. We particularly focused on the role of TNF-α and interferon type I whose role in MG is very analogous to that in several other AIDS. The implication of AIRE, a key factor in central tolerance is also discussed. Finally, if MG is a prototype of AIDS, it has a clear specificity compared to the other AIDS, by the fact that the target organ, the muscle, is not the site of immune infiltration and B cell expansion, but exclusively that of antibody-mediated pathogenic mechanisms. By contrast, the thymus in the early onset subtype frequently undergoes tissue remodeling, resulting in the development of ectopic germinal centers surrounded by high endothelial venules (HEV), as observed in the target organs of many other AIDs.

Clinicopathological study of primary biliary cirrhosis with interface hepatitis compared to autoimmune hepatitis

AIM: To investigate histological and immunohistochemical differences in hepatitis between autoimmune hepatitis (AIH) and primary biliary cirrhosis (PBC) with AIH features.

METHODS: Liver needle biopsies of 41 PBC with AIH features and 43 AIH patients were examined. The activity of periportal and lobular inflammation was scored 0 (none or minimal activity) to 4 (severe), and the degree of hepatitic rosette formation and emperipolesis was semiquantatively scored 0-3. The infiltration of mononuclear cells positive for CD20, CD38, CD3, CD4, and CD8 and positive for immunoglobulins (IgG, IgM, and IgA) at the periportal areas (interface hepatitis) and in the hepatic lobules (lobular hepatitis) were semiquantitatively scored in immunostained liver sections (score 0-6). Serum aspartate aminotransferase (AST), immunoglobulins, and autoantibodies at the time of liver biopsy were correlated with the histological and immunohistochemical scores of individual lesions.

RESULTS: Lobular hepatitis, hepatitic rosette formation, and emperipolesis were more extensive and frequent in AIH than in PBC. CD3+, CD4+, and CD8+ cell infiltration scores were higher in the hepatic lobules and at the interface in AIH but were also found in PBC. The degree of mononuclear cell infiltration correlated well with the degree of interface and lobular hepatitis in PBC, but to a lesser degree in AIH. CD20+ cells were mainly found in the portal tracts and, occasionally, at the interface in both diseases. Elevated AST correlated well with the hepatocyte necroinflammation and mononuclear cell infiltration, specifically CD38+ cells in PBC. No correlation existed between autoantibodies and inflammatory cell infiltration in PBC or AIH. While most AIH cases were IgG-predominant at the interface, PBC cases were divided into IgM-predominant, IgM/IgG-equal, and IgG-predominant types, with the latter sharing several features with AIH.

CONCLUSION: These results suggest that the hepatocellular injuries associated with interface and lobular hepatitis in AIH and PBC with interface hepatitis may not be identical.

Autoimmunity: from black water fever to regulatory function

Autoimmunity is a field that has only been around for a little over a century. Initially, it was thought that autoimmunity could not happen, that the body would never turn on itself (i.e. "horror autotoxicus"). It was only around the First World War that autoimmunity was recognized as the pathogenesis of various diseases, including rheumatoid arthritis. The discovery of Compound E led to successful treatment of patients with autoimmune diseases, but it was not till later that the adverse effects of this class of drugs were elucidated. The "modern" age of autoimmunity began around 1945 with the description of blackwater fever, and most of the subsequent research on hemolytic anemia and the role of an autoantibody in its pathogenesis led to a description of the anti-globulin reaction. The lupus erythematous (LE) cell was recognized in the mid-1940s by Hargreaves. His research carried on into the 1960s. Rheumatoid factor was also first described in the 1940s as yet another serum factor with activity against globulin-coated sheep red blood cells. The concept of autoimmunity really gained a foothold in the 1950s, when autoimmune thyroid disease and idiopathic thrombocytopenia were first described. Much has happened since then, and our understanding of autoimmunity has evolved now to include mechanisms of apoptosis, signaling pathway derangements, and the discovery of subsets of T cells with regulatory activity. The modern day study of autoimmunity is a fascinating area of research, and full understanding of the pathogenesis of autoimmune diseases is far from being completely elucidated.

Current progress in research of overlap syndrome of autoimmune liver diseases

Autoimmune liver diseases (AILDs) include autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC). Overlap syndrome (OS) of AILDs is a relatively infrequent disease that has the combined clinical, biochemical, serological, histological and radiological features of AIH and PBC or PSC, mainly comprising AIH-PBC and AIH-PSC overlap syndromes. The AIH-PBC overlap syndrome is common in adults, while the AIH-PSC overlap syndrome is predominantly found in children. Overlap syndromes have a progressive course and may finally lead to liver cirrhosis and liver failure without treatment. High-dose ursodeoxycholic acid (UDCA) combined with immunosuppressive therapy with corticosteroids and/or azathioprine (AZA) is usually used in both AIH-PBC and AIH-PSC overlap syndromes. At present, liver transplantation is the only option with known therapeutic benefit for end-stage patients.

Unmet needs in the treatment of autoimmunity: from aspirin to stem cells

As rheumatologic diseases became understood to be autoimmune in nature, the drugs used to treat this group of conditions has evolved from herbal or plant derived anti-inflammatory agents, such as salicylates, quinine and colchicine to the many recently approved biological response modifiers. These new drugs, especially the anti-tumor necrosis factor agents, have shown remarkable efficacy in autoimmune diseases, and there are new agents under investigation that will provide additional treatment options. In between, the world was introduced to cortisone and all of its derivatives, as chemical synthesis led to better, more efficacious drugs with lesser side effects. Disease modifying anti-rheumatic agents have actually been around since the first half of the 20th century, but only began to be used in the treatment of autoimmune diseases in the 1970s and 1980s. One advantage is that they have been invaluable in their ability to offer "steroid sparing" to decrease the adverse effects of steroids. Research over the past decade has resulted in a new class of drugs that influence cytokine regulatory pathways such as the Janus associated kinase inhibitors. The promise of personalized medicine now permeates current research into new pharmacological agents for the treatment of autoimmune disease. The new appreciation for the gene-environment interaction in the pathogenesis of most diseases especially those as heterogeneous as autoimmune diseases, has led to our focus on targeted therapies. Add to that the new knowledge of epigenetics and how changes in DNA and histone structure affect expression of genes that can play a role in immune signaling, and we now have a new exciting frontier for cutting edge drug development. The history of treatment of autoimmune diseases is really only a little over a century, but so much has changed, leading to increasing lifespans and improved quality of life of those who suffer from these ailments.

The diagnosis of primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is a chronic liver disease characterized by the immune mediated destruction of small intrahepatic bile duct epithelial cells leading to cholestasis and cirrhosis. The autoimmune basis of PBC is supported by the highly specific anti-mitochondrial antibodies (AMAs) and autoreactive T cells, the former being the basis for diagnosis in the vast majority of cases. Although a rare disease, the incidence rates of PBC have been increasing, possibly due to increased testing and diagnosis as opposed to a true increase in disease incidence. Presently, most cases are asymptomatic and only suspected based upon routine liver tests. Those with symptoms typically complain of pruritus and fatigue. The diagnosis of PBC is based on the presence of at least 2 of 3 key criteria including a persistently elevated serum alkaline phosphatase, the presence of serum AMAs, and liver histology consistent with PBC. Anti-nuclear antibodies specific to PBC are useful in cases in which AMAs are not detected and may indicate a more aggressive course. Ursodeoxycholic acid is the only proven therapy for PBC and in most cases can delay or prevent disease progression. However, a subgroup of patients does not adequately respond to ursodeoxycholic acid and for whom new therapies are needed.

Anti-CD40 ligand monoclonal antibody delays the progression of murine autoimmune cholangitis

While there have been significant advances in our understanding of the autoimmune responses and the molecular nature of the target autoantigens in primary biliary cirrhosis (PBC), unfortunately these data have yet to be translated into new therapeutic agents. We have taken advantage of a unique murine model of autoimmune cholangitis in which mice expressing a dominant negative form of transforming growth factor β receptor II (dnTGFβRII), under the control of the CD4 promoter, develop an intense autoimmune cholangitis associated with serological features similar to human PBC. CD40-CD40 ligand (CD40L) is a major receptor-ligand pair that provides key signals between cells of the adaptive immune system, prompting us to determine the therapeutic potential of treating autoimmune cholangitis with anti-CD40L antibody (anti-CD40L; MR-1). Four-week-old dnTGFβRII mice were injected intraperitoneally with either anti-CD40L or control immunoglobulin (Ig)G at days 0, 2, 4 and 7 and then weekly until 12 or 24 weeks of age and monitored for the progress of serological and histological features of PBC, including rigorous definition of liver cellular infiltrates and cytokine production. Administration of anti-CD40L reduced liver inflammation significantly to 12 weeks of age. In addition, anti-CD40L initially lowered the levels of anti-mitochondrial autoantibodies (AMA), but these reductions were not sustained. These data indicate that anti-CD40L delays autoimmune cholangitis, but the effect wanes over time. Further dissection of the mechanisms involved, and defining the events that lead to the reduction in therapeutic effectiveness will be critical to determining whether such efforts can be applied to PBC.

Immunologic and genetic considerations of cutaneous lupus erythematosus: a comprehensive review

Cutaneous lupus erythematosus (CLE) refers to those subtypes of lupus erythematosus (LE) that have predominantly skin manifestations. Discoid lupus erythematosus (DLE), subacute cutaneous lupus erythematosus (SCLE), LE panniculitis (LEP) and lupus erythematosus tumidus (LET) all fall into the category of CLE. The pathogenesis of CLE is likely multifactorial. UV irradiation has been shown to induce keratinocyte apoptosis. Impaired clearance of apoptotic cells is a potential mechanism for the development of CLE. UV irradiation can also induce externalization of autoantigens such as Ro/SSA, exposing them to circulating autoantibodies. Some drugs have been associated with CLE. Possible mechanisms include stimulation of an immune response through disruption of central tolerance and altered T cell function. T17 cells may also play a role in the pathogenesis of CLE as they have been detected in skin lesions of LE. Treg cells have been found to be decreased in LE lesions, which may contribute to the breakdown of self-tolerance. Epidermal Langerhans cells are reduced in CLE while plasmacytoid DCs are increased in the lesions of CLE, suggesting that DCs may also play an important role in the pathogenesis of CLE. Type I IFN- and TNF-α are both upregulated in lesions of CLE. Other cytokines such as IL-6 and IL-17 are also implicated in the pathogenesis of CLE. Cellular and cytokine networks can be impacted by environmental factors and genetic variations and this can result in an increased risk of developing autoimmune diseases such as CLE.