Epidemiology of HEV Infection in Blood Donors in Southern Switzerland.

From 2014 to 2016, the number of hepatitis E virus (HEV) infections in southern Switzerland increased dramatically and suggested food as a potential infection reservoir. We evaluated the effects of food control measures introduced to limit HEV infections, assessing anti-HEV IgG and IgM rates in blood donors before and after the implementation of food control measures in 2017. From 2012 to 2013, we screened 1283, and from 2017 to 2019, we screened 1447 donors for IgG and IgM antibodies. No statistically significant differences were detected for IgG (32.8% from 2012 to 2013 vs. 31.1% from 2017 to 2019, p = 0.337) or IgM rates (2.0% from 2012 to 2013 vs. 2.8% from 2017 to 2019, p = 0.21). Rural provenience and age > 66 are predictors for positive IgG serology. A total of 5.9% of 303 donors included in both groups lost IgG positivity. We also determined nucleic acid testing (NAT) rates after the introduction of this test in 2018, comparing 49,345 donation results from southern Switzerland with those of 625,559 Swiss donor controls, and only 9 NAT-positive donors were found from 2018 to 2023. The high HEV seroprevalence in southern Switzerland may depend on different food supply chains in rural and urban areas. Local preventive measures probably have a limited impact on blood HEV risk; thus, continuous NAT testing is recommended.

HCV disease burden and population segments in Switzerland.

BACKGROUND: Switzerland has made strides towards hepatitis C virus elimination, but as of 2019, elimination was not guaranteed. However, political interest in viral hepatitis has been increasing. We sought to develop a better understanding of Switzerland's progress towards HCV elimination and the profile of remaining HCV-RNA-positive patients. METHODS: A previously described Markov model was updated with recent diagnosis and treatment data and run to generate new forecasts for HCV disease burden. Two scenarios were developed to evaluate HCV morbidity and mortality under the status quo and a scenario that achieves the Swiss Hepatitis Strategy Elimination targets. Next, an analysis was conducted to identify population segments bearing a high burden of disease, where future elimination efforts could be directed. RESULTS: At the beginning of 2020, an estimated 32 100 viremic infections remained in Switzerland (0.37% viremic prevalence). Adult (≥18 years of age) permanent residents born abroad represented the largest subpopulation, accounting for 56% of HCV infections. Thirteen countries accounted for ≥60% of viremic infections amongst permanent residents born abroad, with most people currently residing in Zurich, Vaud, Geneva, Bern, Aargau and Ticino. Amongst Swiss-born HCV-RNA-positive persons, two-thirds had a history of IDU, corresponding to 33% of total infections. CONCLUSIONS: In Switzerland, extra efforts for diagnosis and linkage to care are warranted in foreign-born populations and people with a history of drug use. Population-level measures (eg increasing the number of providers, increase screening) can identify patients who may have otherwise fallen through the gaps or avoided care because of stigma.

Control of Raw Pork Liver Sausage Production Can Reduce the Prevalence of HEV Infection.

After an acute hepatitis E (HEV) outbreak in Southern Switzerland, in January 2017 the local public health authorities started an active program of food chain control and public education. In this retrospective study, we analysed all laboratory-confirmed acute cases of HEV infection diagnosed between 2014 and 2020. In the period before the public health intervention, the number of cases increased steadily from 2014 (4 of 40 tests, 10%) reaching a peak in the last quarter of 2016 (42 of 285 tests, 14.7 %). Afterwards, the number of positive cases decreased steadily, reaching its lowest value (0.3%) in the second quarter of 2019. There was a statistically significant difference between the frequency of positive cases and period of testing, i.e., before and after the introduction of the public health interventions. Our study shows that active public health measures to control sausages containing raw pork liver can reduce the prevalence of HEV infection.

ABCB4 variants in adult patients with cholestatic disease are frequent and underdiagnosed.

BACKGROUND: Heterozygous ABCB4 variants are not routinely tested in adults with cholestasis because of their supposed rarity and high costs. METHODS: Nineteen adult patients presenting with unexplained cholestasis, and/or recurrent gallstones were included; genotyping was not done in five due to lack of health insurance approval. RESULTS: heterozygous ABCB4 variants were identified in seven patients, followed by cascade testing of 12 family members: one patient underwent liver transplantation at age 40 for end-stage liver disease; one had compensated cirrhosis; all symptomatic adults had gallstones, including four with low phospholipid-associated cholelithiasis; four had intrahepatic cholestasis of pregnancy; all children and one 54-year old female were asymptomatic. Genotype: Families A and C: c.2211G>A (p.Ala737=) combined with c.959C>T (p.Ser320Phe) in one subject; Family B: c.1130T>C (p.Ile377Thr); Family D: large deletion removing ABCB4 exons 1-4 plus ABCB1, RUNDC3B, SLC25A40, DBF4, ADAM22 exons 1-3; Family E: c.1565T>C (p.Phe522Ser) ; Family F: c.1356+2T>C combined with c.217C>G (p.Leu73Val). All patients responded to ursodeoxycholic acid. CONCLUSIONS: We found ABCB4 variants in half of the adults with unexplained cholestasis and/or recurrent gallstones presenting at our center, suggesting that this condition is underdiagnosed and undertreated, with serious consequences not only for the patients and their families, but also in terms of healthcare costs.

Corrigendum to "Alcoholic and Nonalcoholic Liver Disease: Diagnostic Assessment and Therapeutic Perspectives".

[This corrects the article DOI: 10.1155/2019/8691502.].

Neurologic complications of acute hepatitis E virus infection.

OBJECTIVE: To assess the prevalence and clinical features of neurologic involvement in patients with acute hepatitis E virus (HEV) infection in Southern Switzerland. METHODS: Among 1,940 consecutive patients investigated for acute hepatitis E, we identified 141 cases of acute of HEV infection (anti-HEV immunoglobulin M and immunoglobulin G both reactive and/or HEV RNA positive) between June 2014 and September 2017. Neurologic cases were followed up for 6 months. We compared patients with and without neurologic symptoms. RESULTS: Neurologic symptoms occurred in 43 acute HEV cases (30.4%) and consisted of neuralgic amyotrophy (NA, n = 15, 10.6%) and myalgia (n = 28, 19.8%). All NA cases were immunocompetent. Men had higher odds (OR = 5.2, CI 1.12-24.0, p = 0.03) of developing NA after infection with HEV, and in 3 couples simultaneously infected with HEV, only men developed NA. Bilateral involvement of NA was predominant (2:1) and occurred only in men. Seven NA cases were viremic (all genotype 3), but HEV was undetectable in their CSF. In the acute phase of NA, 9 patients were treated with intravenous immunoglobulin and 4 with prednisone, reporting no side effects and improvement in pain and strength. Myalgia occurred both without (n = 16) or with (n = 12) concomitant elevated serum creatinine kinase. Seven cases with myalgia in the shoulder girdle did not have muscle weakness ("forme fruste" of NA). CONCLUSIONS: Neurologic symptoms occurred in one-third of acute HEV infections and consisted of NA and myalgia. NA seems to occur more frequently in men infected by HEV and has a predominant (but not exclusive) bilateral involvement.

Nonalcoholic steatohepatitis before and after liver transplant: keeping up with the times.

INTRODUCTION: In the last years, nonalcoholic steatohepatitis (NASH) has become a leading indication for liver transplant (LT). After transplant, both recurrent and de novo nonalcoholic fatty liver disease (NAFLD) can be commonly diagnosed. However, dedicated surveillance programs for patients with pre- or post-transplant NAFLD are not available. Areas covered: Patients waiting for LT for NASH show specific peculiarities and would deserve targeted stratification of mortality risk. Obesity, hyperlipidemia, and diabetes mellitus can be often found after transplant. These conditions, together with immunosuppressive regimen, make LT recipients a high-risk population for both recurrent and de novo NAFLD. Development of fatty liver disease after LT has a relevant impact on both morbidity and mortality. Expert commentary: A targeted stratification of neoplastic and cardiovascular risk for patients with NASH waiting for LT would be mandatory. In both pre- and post-transplant period, NAFLD should be considered not only a liver disease but also a cardiovascular risk factor. Patients within Transplant Program, especially those with known metabolic risk factors, should be followed with personalized diagnostic and life-style interventions before and after LT.

Antibiotic administration after cholecystectomy for acute mild-moderate cholecystitis: a PRISMA-compliant meta-analysis.

INTRODUCTION: Acute cholecystitis is a common disease and a frequent cause of emergency admission to surgical wards. Evidence regarding antibiotic administration in urgent procedures is limited and remains a contentious issue. According to the Tokyo guidelines, the antibiotic administration should be guided by the severity of cholecystitis, but internationally accepted guidelines are lacking. In particular, the need to perform antibiotic therapy after laparoscopic cholecystectomy is controversial for mild and moderate acute calculous cholecystitis (Tokio I and II). MATERIALS AND METHODS: We performed a comprehensive computer literature search of PubMed and MEDLINE databases in accordance to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Guidelines. We selected patients treated with cholecystectomy for mild or moderate acute calculous cholecystitis (Tokio I or II), only randomized controlled trials, (post-operative antibiotic administration versus placebo or untreated), data about local or systemic infection rate in the next 30 days after surgery. RESULTS: Three hundred and fifty-nine articles were identified, and three articles were considered eligible for the meta-analysis, including 676 patients. Overall surgical site infections were documented in 18 (5.49%) of 328 patients treated with post-operative antibiotics versus 25 (7.18%) of 348 patients treated without post-operative antibiotics. Overall results and the subgroup analysis (superficial and deep incisional infection and organ/space infection) showed no statistically significant reduction of surgical site infections rate under antibiotic therapy. CONCLUSIONS: Our meta-analysis shows no significant benefit of extended antibiotic therapy in reducing SSI after cholecystectomy for mild and moderate acute cholecystitis (Tokio I and II). Further RCTs with adequate statistical power and involving a higher number of patients with subgroups are needed to better evaluate the benefit of post-operative antibiotic treatment in reducing the rate of organ/space surgical site infections.

Autoimmune liver disease serology in acute hepatitis E virus infection.

The etiology of autoimmune hepatitis (AIH) is unknown, though hepatotropic viruses may be potential triggers. Hepatitis E virus (HEV) infection, an increasingly recognized cause of acute hepatitis, has been misdiagnosed as AIH due to the occurrence of autoantibodies during its acute phase. It has also been suggested that HEV infection may lead to or unmask AIH. The HEV seroprevalence has been ascertained in patients with AIH, but the prevalence of AIH-related autoantibodies in patients with HEV infection has not been systematically tested. We aimed to investigate whether acute HEV infection is associated with the presence of AIH-relevant autoantibodies, following the liver autoimmune serology guidelines of the International AIH Group. We tested 48 patients with acute HEV infection. Half of them had at least one autoantibody, 17% two autoantibodies. Anti-nuclear antibody (ANA) were detected in 16 (33%), anti-smooth muscle antibody (SMA) in 10 (21%), and anti-neutrophil cytoplasmic antibody (ANCA) in 7 (14.6%). Of note, two patients showed SMA with VG or VGT patterns and five had ANA with homogeneous appearance, both being typical of AIH type 1. Other AIH-specific autoantibodies were negative. Atypical anti-mitochondrial antibody, without evidence of primary biliary cholangitis, was positive in one patient, disappearing at follow-up. Follow-up (median 12 months) serum was available from seven autoantibody positive patients: two became negative, while five remained positive, although no patient developed AIH to date. In conclusion, autoantibodies are frequently present during acute HEV infection, indicating that HEV should always be excluded before diagnosing AIH. Importantly, a minority of patients with acute hepatitis E develops AIH-specific autoantibodies, and, though they did not progress to autoimmune liver disease in the short-term, they warrant long-term monitoring.

Hepatitis E virus as a cause of acute hepatitis acquired in Switzerland.

BACKGROUND: Autochthonous hepatitis E is increasingly recognized as zoonotic infection in western countries. Serological assays have varying sensitivity and specificity. METHODS: We implemented molecular testing to identify and characterize acute hepatitis E acquired in Switzerland. RESULTS: Ninety-three cases of mostly symptomatic acute hepatitis E acquired in Switzerland were documented by PCR between November 2011 and December 2016. Median HEV RNA was 7.5 x 104 IU/mL (range, 5.3 to 4.7 x 107 IU/mL). HEV genotyping was successful in 78 patients, revealing genotype 3 in 75 and genotype 4 in three patients. Phylogenetic analyses revealed a few limited geographical and temporal clusters. Of the 91 patients with available anti-HEV IgM serology, four were negative; three of these were also IgG-negative, likely as a result of immunosuppression, and one was IgG-positive, a constellation compatible with HEV reinfection. Median age of the patients was 58 years (range, 20-80 years); 71 (76.3%) were men and 49 of these (69.0%) were ≥ 50 years old. The clinical course was particularly severe in patients with underlying chronic liver disease, with fatal outcome in two patients. Six patients (6.5%) presented with neuralgic amyotrophy. CONCLUSIONS: Nucleic acid-based diagnosis reveals HEV as a relevant cause of acute hepatitis in Switzerland. Middle-aged and elderly men constitute the majority of symptomatic patients. Testing for HEV should be included early in the diagnostic workup of acute hepatitis and of neuralgic amyotrophy, a typical extrahepatic manifestation of HEV genotype 3 infection.

Progress toward implementing the Swiss Hepatitis Strategy: Is HCV elimination possible by 2030?

Catalyzed by the concerns over the growing public health and economic burden of Hepatitis C virus (HCV) in Switzerland, a diverse group of experts and patient representatives came together in 2014 to develop the Swiss Hepatitis Strategy, setting targets for the elimination of viral hepatitis in Switzerland by 2030. Previous studies have reported the estimated number of chronic HCV infections and forecasted burden of disease given different intervention strategies. However, given new prevalence data by the Swiss Federal Office of Public Health, which decreased total infections by about half, an updated analysis is warranted. We aimed to provide an updated viremic prevalence estimate for Switzerland and evaluate the impact on forecasted liver related morbidity and mortality of an 'inaction' scenario and intervention scenarios to achieve the Global Health Sector Strategy for Viral Hepatitis and Swiss Hepatitis Strategy goals by 2030. A Markov disease-progression model was used to calculate the present and future burden of HCV infection by disease stage according to these different strategies. In 2017, there were an estimated 36,800 (95% UI: 26,900-39,200) viremic infections in Switzerland. Given the current standard of care, total viremic infections are expected to decline by 45%, while cases of decompensated cirrhosis, hepatocellular carcinoma, and liver-related deaths will decrease by 20%. If treatment and diagnosis efforts were to cease in 2018, late stage HCV-related morbidity and mortality would increase by 90-100% by 2030. Increasing treatment and diagnosis to achieve the Global Health Sector Strategy or Swiss Hepatitis Strategy goals by 2030, will reduce the number of chronic infections to less than 13,000 and 4,000, respectively. Although the HCV epidemic is declining in Switzerland, efforts to expand diagnosis and treatment are needed to achieve elimination by 2030.

Geoepidemiology of Primary Biliary Cholangitis: Lessons from Switzerland.

No data on primary biliary cholangitis (PBC) are available in Switzerland. We established a national patient cohort to obtain information on PBC phenotypes and disease course in Switzerland. Local databases in all university hospitals and in two large secondary centers were searched for case finding. In addition, all primary care physicians, gastroenterologists, rheumatologists, and dermatologists were invited to contribute patients from their own medical records. PBC diagnosis was centrally reviewed. Five hundred one PBC patients were identified, 474 were included in data analysis, and 449 of them were enrolled by tertiary centers. The catchment area accounts for approximately one third of the Swiss population or approximately 2.8 million inhabitants. The median age at diagnosis was 53 years, 84% were women, and 86% were anti-mitochondrial antibody positive. The median follow-up was 5.4 years, 12.6% experienced a liver-related endpoint. Splenomegaly was present at diagnosis in one quarter of patients and in half of male patients. Approximately one third were non-responders to ursodeoxycholic acid (UDCA). The median transplant-free survival at 10 years was 85%. The following variables were independently associated with poor outcome: low platelet count at baseline (HR = 0.99, p < 0.0001), elevated alkaline phosphatase at baseline (HR = 1.36, p < 0.0001), elevated bilirubin at baseline (HR = 1.11, p = 0.001), and elevated alanine aminotransaminase (HR = 1.35, p = 0.04) after 12 months of UDCA therapy. The AUROC for the UK-PBC risk score at 5, 10, and 15 years was 0.82. The AUROC for the Globe score at 5, 10, and 15 years was 0.77. Patients included in this study are currently being enrolled in a prospective nationwide registry with biobank, taking advantage of the collaboration network generated by this study. Our study provides the first snapshot of PBC in Switzerland, describing a diagnostic delay with one quarter of patients diagnosed when already in the cirrhotic stage. We were also able to externally validate the UK-PBC risk score and the Globe score. The ongoing nationwide prospective registry will be fundamental to improve disease awareness and interdisciplinary collaborations and will serve as a platform for clinical and translational research. TRIAL REGISTRATION NUMBER: clinicaltrials.gov : NCT02846896; SNCTP000001870.

Birth cohort distribution and screening for viraemic hepatitis C virus infections in Switzerland.

OBJECTIVE: In Switzerland, fewer than 40% of hepatitis C virus (HCV) infected individuals have been diagnosed. The aim of this project was to analyse the distribution of HCV cases in order to develop better detection strategies. STUDY DESIGN: Historical data on the HCV-infected population in Switzerland were obtained from published literature, unpublished data and government reports. A disease progression model was used to age the infected population to 2015. The HCV distribution was then used to identify 5-year age cohorts with the highest HCV prevalence. The estimated number of cases needed to screen within an age cohort was calculated using the estimated viraemic prevalence, removing the percent previously diagnosed. RESULTS: In 2015, the median age of the viraemic HCV infected population was 49 years, with 75% of the population born between 1951 and 1985. Random screening of the general population could identify one new viraemic HCV case per 159 persons screened, compared with targeted birth cohort screening, which could identify one new viraemic HCV case per 90-99 persons screened. CONCLUSION: Considering only the direct cost of screening and treatment informing tests, targeted screening by birth cohort is more effective and cost effective than random screening in the general population.

HBV genotypes and response to tenofovir disoproxil fumarate in HIV/HBV-coinfected persons.

BACKGROUND: Hepatitis B virus (HBV) genotypes can influence treatment outcome in HBV-monoinfected and human immunodeficiency virus (HIV)/HBV-coinfected patients. Tenofovir disoproxil fumarate (TDF) plays a pivotal role in antiretroviral therapy (ART) of HIV/HBV-coinfected patients. The influence of HBV genotypes on the response to antiviral drugs, particularly TDF, is poorly understood. METHODS: HIV/HBV-co-infected participants with detectable HBV DNA prior to TDF therapy were selected from the Swiss HIV Cohort Study. HBV genotypes were identified and resistance testing was performed prior to antiviral therapy, and in patients with delayed treatment response (>6 months). The efficacy of TDF to suppress HBV (HBV DNA <20 IU/mL) and the influence of HBV genotypes were determined. RESULTS: 143 HIV/HBV-coinfected participants with detectable HBV DNA were identified. The predominant HBV genotypes were A (82 patients, 57 %); and D (35 patients, 24 %); 20 patients (14 %) were infected with multiple genotypes (3 % A + D and 11 % A + G); and genotypes B, C and E were each present in two patients (1 %). TDF completely suppressed HBV DNA in 131 patients (92 %) within 6 months; and in 12 patients (8 %), HBV DNA suppression was delayed. No HBV resistance mutations to TDF were found in patients with delayed response, but all were infected with HBV genotype A (among these, 5 patients with genotype A + G), and all had previously been exposed to lamivudine. CONCLUSION: In HIV/HBV-coinfected patients, infection with multiple HBV genotypes was more frequent than previously reported. The large majority of patients had an undetectable HBV viral load at six months of TDF-containing ART. In patients without viral suppression, no TDF-related resistance mutations were found. The role of specific genotypes and prior lamivudine treatment in the delayed response to TDF warrant further investigation.

Modeling the Health and Economic Burden of Hepatitis C Virus in Switzerland.

BACKGROUND: Chronic hepatitis C virus infection is a major cause of liver disease in Switzerland and carries a significant cost burden. Currently, only conservative strategies are in place to mitigate the burden of hepatitis C in Switzerland. This study expands on previously described modeling efforts to explore the impact of: no treatment, and treatment to reduce HCC and mortality. Furthermore, the costs associated with untreated HCV were modeled. METHODS: Hepatitis C disease progression and mortality were modeled. Baseline historical assumptions were collected from the literature and expert interviews and strategies were developed to show the impact of different levels of intervention (improved drug cure rates, treatment and diagnosis) until 2030. RESULTS: Under the historical standard of care, the number of advanced stage cases was projected to increase until 2030, at which point the annual economic burden of untreated viremic infections was projected to reach €96.8 (95% Uncertainty Interval: €36 - €232) million. Scenarios to reduce HCV liver-related mortality by 90% by 2030 required treatment of 4,190 ≥F2 or 3,200 ≥F3 patients annually by 2018 using antivirals with a 95% efficacy rate. Delaying the implementation of these scenarios by 2 or 5 years reduced the impact on mortality to 75% and 57%, respectively. CONCLUSIONS: With today's treatment efficacy and uptake rates, hepatitis C disease burden is expected to increase through 2030. A substantial reduction in disease burden can be achieved by means of both higher efficacy drugs and increased treatment uptake. However, these efforts cannot be undertaken without a simultaneous effort to diagnose more infections.

Survival of hepatocellular carcinoma patients is significantly improving: a population-based study from southern Switzerland.

BACKGROUND: During the last 20 years, relevant diagnostic procedures and advanced treatments have been progressively introduced in the management of hepatocellular carcinoma (HCC). The aim of the present study was to assess up-to-date survival trends for HCC in southern Switzerland, a region with one of the highest incidence rates in the country. METHODS: HCCs diagnosed in 1996-2009 were selected by the Ticino Cancer Registry. Cancer-specific survival (CSS) analysis was performed using the Kaplan-Meier method by calendar period: 1996-2000, 2001-2005 and 2006-2009. The log-rank test was used to detect differences in survival curves. Simultaneous assessment of prognostic factors was performed by a multivariate analysis using the Cox proportional-hazards regression model. RESULTS: 619 HCCs were analysed. There was a significant increase of patients undergoing transarterial chemoembolisation (TACE), whereas patients undergoing curative or palliative supportive treatments remained unchanged (p < 0.0001). No shift to earlier stages was detected. Significant differences in CCS were observed by age-group (p < 0.0001), diagnosis period (p < 0.0001), diagnosis technique (p = 0.0035), Barcelona-Clinic liver cancer stage (p < 0.0001), treatment (p < 0.0001). Multivariate analysis confirmed the independent impact on CSS of factors above mentioned, not including the diagnosis technique. Death risk was higher for patients diagnosed in 1996-2000 (HR: 1.32; 95% CI: 1.03; 1.68) and 2001-2005 (HR: 1.33; 95% CI: 1.05; 1.67) in comparison with 2006-2009 (reference group). CONCLUSIONS: The current population-based report describes a major increase in HCC survival. Simultaneously an increased use of TACE has been detected, probable cofactor of the observed survival increase. Possibly additional efforts could be made to decrease the HCC stage at diagnosis through active surveillance of cirrhotic patients to allow an increase in curative treatments. For sure efforts should be made to comply with a standardised staging system for HCC, particularly for comparative population-based issues.

Hepatitis B virus infection is associated with impaired immunological recovery during antiretroviral therapy in the Swiss HIV cohort study.

Hepatitis B virus (HBV) infection is a major cause of morbidity and mortality in human immunodeficiency virus (HIV)-infected patients worldwide. It is unclear whether HIV-related outcomes are affected by HBV coinfection. We compared virological suppression and immunological recovery during antiretroviral therapy (ART) of patients of different HBV serological status in the Swiss HIV Cohort Study. CD4 cell recovery during ART was significantly impaired in hepatitis B surface antigen-positive patients and in those with anti-hepatitis B core antigen alone compared with HBV-uninfected patients, despite similar virological efficacy of ART. CD4 increase in patients with resolved HBV infection was similar to that in HBV-uninfected individuals.

Virus-specific immune response in HBeAg-negative chronic hepatitis B: relationship with clinical profile and HBsAg serum levels.

BACKGROUND AIMS: The immune impairment characterizing chronic hepatitis B (cHBV) infection is thought to be the consequence of persistent exposure to viral antigens. However, the immune correlates of different clinical stages of cHBV and their relation with different levels of HBsAg have not been investigated. The aim of the present study was to evaluate the relationship between HBV-specific T cells response and the degree of in vivo HBV control and HBsAg serum levels in HBeAg-HBeAb+ cHBV. METHODS: Peripheral blood mononuclear cells from 42 patients with different clinical profiles (treatment-suppressed, inactive carriers and active hepatitis) of cHBV, 6 patients with resolved HBV infection and 10 HBV-uninfected individuals were tested with overlapping peptides spanning the entire HBV proteome. The frequency and magnitude of HBV-specific T cell responses was assessed by IFNγ ELISPOT assay. Serum HBsAg was quantified with a chemiluminescent immunoassay. RESULTS: The total breadth and magnitude of HBV-specific T cell responses did not differ significantly between the four groups. However, inactive carriers targeted preferentially the core region. In untreated patients, the breadth of the anti-core specific T cell response was inversely correlated with serum HBsAg concentrations as well as HBV-DNA and ALT levels and was significantly different in patients with HBsAg levels either above or below 1000 IU/mL. The same inverse association between anti-core T cell response and HBsAg levels was found in treated patients. CONCLUSIONS: Different clinical outcomes of cHBV infection are associated with the magnitude, breadth and specificity of the HBV-specific T cell response. Especially, robust anti-core T cell responses were found in the presence of reduced HBsAg serum levels, suggesting that core-specific T cell responses can mediate a protective effect on HBV control.

Differential boosting of innate and adaptive antiviral responses during pegylated-interferon-alpha therapy of chronic hepatitis B.

BACKGROUND & AIMS: A better understanding of the immunomodulatory effects of PegIFNα therapy could allow more rational optimisation of future therapeutic approaches in chronic HBV infection. In this study, we evaluated dynamic changes in the innate and adaptive arms of the immune system induced by PegIFNα. METHODS: PBMC were obtained from a cohort of patients with eAg-negative CHB before, during and after PegIFNα treatment. The number, phenotype and function of global and virus-specific T cells and NK cells were analyzed by flow cytometry and serum cytokines by ELISA or CBA. RESULTS: The absolute number of CD8 T cells was strikingly reduced on PegIFNα therapy (p<0.001), with a predominant loss of end-stage effectors, including CMV-specific CD8 T cells. There was no significant recovery of the exhausted HBV-specific CD8 T cell response. By contrast, PegIFNα was able to potently and cumulatively drive the proliferation and expansion in absolute numbers of CD56(bright) NK cell numbers (p<0.001), with induction of the pro-proliferative cytokine IL-15. Expanded CD56(bright) NK cells showed enhanced expression of activation markers and the activating receptor NKp46, accompanied by augmentation of TRAIL and IFN-γ expression (p<0.001). Peak virological response (temporal within individual patients and cross-sectional within the cohort) correlated with the degree of expansion of functional CD56(bright) NK cells. CONCLUSIONS: IFN-α mediates divergent effects on the innate and adaptive arms of the immune system in vivo. The efficacy of PegIFNα may be limited by its depleting effect on CD8 T cells; conversely, it can cumulatively drive proliferation, activation and antiviral potential of CD56(bright) NK cells.