Decreased immunogenicity of recombinant hepatitis B vaccine in chronic hepatitis C

Overview of Hepatitis B Vaccine Non-Response and Associated B Cell Amnesia: A Scoping Review

BACKGROUND

The advent of the hepatitis B vaccine has achieved tremendous success in eradicating and reducing the burden of hepatitis B infection, which is the main culprit for hepatocellular carcinoma-one of the most fatal malignancies globally. Response to the vaccine is achieved in about 90-95% of healthy individuals and up to only 50% in immunocompromised patients. This review aimed to provide an overview of hepatitis B vaccine non-response, the mechanisms involved, B cell amnesia, and strategies to overcome it.

METHODS

Databases, including Google Scholar, PubMed, Scopus, Cochrane, and ClinicalTrials.org, were used to search and retrieve articles using keywords on hepatitis B vaccine non-response and B cell amnesia. The PRISMA guideline was followed in identifying studies, screening, selection, and reporting of findings.

RESULTS

A total of 133 studies on hepatitis B vaccine non-response, mechanisms, and prevention/management strategies were included in the review after screening and final selection. Factors responsible for hepatitis B vaccine non-response were found to include genetic, immunological factors, and B cell amnesia in healthy individuals. The genetic factors were sex, HLA haplotypes, and genetic polymorphisms in immune response markers (cytokines). Non-response was common in conditions of immunodeficiency, such as renal failure, haemodialysis, celiac disease, inflammatory bowel disease, hepatitis C co-infection, and latent hepatitis B infection. Others included diabetes mellitus and HIV infection. The mechanisms involved were impaired immune response by suppression of response (T helper cells) or induced suppression of response (through regulatory B and T cells).

DISCUSSION

A comprehensive and careful understanding of the patient factors and the nature of the vaccine contributes to developing effective preventive measures. These include revaccination or booster dose, vaccine administration through the intradermal route, and the use of adjuvants in the vaccine.

Vaccination in Patients with Liver Cirrhosis: A Neglected Topic

Patients with liver cirrhosis, due to their weakened innate and adaptive immunity, are more prone to frequent and severe vaccine-preventable infections. Moreover, impaired adaptive immunity results in a limited antibody response to vaccines. Despite this suboptimal antibody response, vaccines have proven to be very effective in reducing severe outcomes and deaths in these patients. In the Western world, regulatory authorities and scientific liver societies (e.g., AASLD and EASL) have recommended vaccinations for cirrhotic patients. However, despite these strong recommendations, vaccine coverage remains suboptimal. Improving vaccine effectiveness and safety information, providing comprehensive counseling to patients, fact-checking to combat fake news and disinformation and removing barriers to vaccination for disadvantaged individuals may help overcome the low coverage rate. In view of this, vaccines should be administered early in the course of chronic liver diseases, as their efficacy declines with the increasing severity of the disease.

A Comprehensive Review of Hepatitis B Vaccine Nonresponse and Associated Risk Factors

Hepatitis B virus (HBV) infection remains a significant global health concern worldwide, contributing to high rates of mortality and morbidity, including chronic hepatitis B, cirrhosis, and hepatocellular carcinoma (HCC). Universal vaccination programs have significantly reduced the rate of HBV transmission; however, a subset of individuals fail to develop a protective immune response following vaccination and are termed nonresponders. A comprehensive search strategy using the PubMed, Google Scholar, and Web of Science databases was employed to search for relevant studies using keywords including "hepatitis B vaccine", "vaccine nonresponse", "immunogenicity", "immune response to the hepatitis B vaccine", and "associated risk factors". Factors influencing the vaccine's response include demographic factors, such as age and sex, with increased nonresponse rates being observed in older adults and males. Obesity, smoking, and alcohol consumption are lifestyle factors that decrease the vaccine response. Medical conditions, including diabetes, chronic kidney and liver diseases, HIV, celiac disease, and inflammatory bowel disease, affect the vaccine response. Major histocompatibility complex (MHC) haplotypes and genetic polymorphisms linked to immune regulation are genetic factors that further influence the vaccine's effectiveness. To reduce the global burden of hepatitis B infection, it is essential to understand these factors to improve vaccine effectiveness and develop individualized vaccination strategies.

Lasting differential gene expression of circulating CD8 T cells in chronic HCV infection with cirrhosis identifies a role for Hedgehog signaling in cellular hyperfunction

Background

The impact of chronic hepatic infection on antigen non-specific immune cells in circulation remains poorly understood. We reported lasting global hyperfunction of peripheral CD8 T cells in HCV-infected individuals with cirrhosis. Whether gene expression patterns in bulk CD8 T cells are associated with the severity of liver fibrosis in HCV infection is not known.

Methods

RNA sequencing of blood CD8 T cells from treatment naïve, HCV-infected individuals with minimal (Metavir F0-1 ≤ 7.0 kPa) or advanced fibrosis or cirrhosis (F4 ≥ 12.5 kPa), before and after direct-acting antiviral therapy, was performed. CD8 T cell function was assessed by flow cytometry.

Results

In CD8 T cells from pre-DAA patients with advanced compared to minimal fibrosis, Gene Ontology analysis and Gene Set Enrichment Analysis identified differential gene expression related to cellular function and metabolism, including upregulated Hedgehog (Hh) signaling, IFN-α, -γ, TGF-β response genes, apoptosis, apical surface pathways, phospholipase signaling, phosphatidyl-choline/inositol activity, and second-messenger-mediated signaling. In contrast, genes in pathways associated with nuclear processes, RNA transport, cytoskeletal dynamics, cMyc/E2F regulation, oxidative phosphorylation, and mTOR signaling, were reduced. Hh signaling pathway was the top featured gene set upregulated in cirrhotics, wherein hallmark genes GLI1 and PTCH1 ranked highly. Inhibition of Smo-dependent Hh signaling ablated the expression of IFN-γ and perforin in stimulated CD8 T cells from chronic HCV-infected patients with advanced compared to minimal fibrosis. CD8 T cell gene expression profiles post-DAA remained clustered with pre-DAA profiles and disparately between advanced and minimal fibrosis, suggesting a persistent perturbation of gene expression long after viral clearance.

Conclusions

This analysis of bulk CD8 T cell gene expression in chronic HCV infection suggests considerable reprogramming of the CD8 T cell pool in the cirrhotic state. Increased Hh signaling in cirrhosis may contribute to generalized CD8 T cell hyperfunction observed in chronic HCV infection. Understanding the lasting nature of immune cell dysfunction may help mitigate remaining clinical challenges after HCV clearance and more generally, improve long term outcomes for individuals with severe liver disease.

Characterization of "Off-Target" Immune Modulation Induced by Live Attenuated Yellow Fever Vaccine

BACKGROUND

Live attenuated vaccines alter immune functions and are associated with beneficial outcomes. We previously demonstrated that live attenuated yellow fever virus (YFV) vaccine (LA-YF-Vax) dampens T-cell receptor (TCR) signaling in vitro via an RNA-based mechanism. We examined study participants before and after LA-YF-Vax to assess TCR-mediated functions in vivo.

METHODS

Serum samples and peripheral blood mononuclear cells (PBMCs) were obtained before and after LA-YF-Vax (with or without additional vaccines) or quadrivalent influenza vaccine. TCR-mediated activation was determined by interleukin 2 release or phosphorylation of the lymphocyte-specific Src kinase. TCR-regulating phosphatase (protein tyrosine phosphatase receptor type E [PTPRE]) expression was also measured.

RESULTS

Compared with prevaccination findings, LA-YF-Vax recipient PBMCs demonstrated transient reduction in interleukin 2 release after TCR stimulation and PTPRE levels, unlike in control participants who received quadrivalent influenza vaccine. YFV was detected in 8 of 14 participants after LA-YF-Vax. After incubation of healthy donor PBMCs in serum-derived extracellular vesicles prepared from LA-YF-Vax recipients, TCR signaling and PTPRE levels were reduced after vaccination, even in participants without detectable YFV RNA.

CONCLUSIONS

LA-YF-Vax reduces TCR functions and PTPRE levels after vaccination. Extracellular vesicles from serum recapitulated this effect in healthy cells. This likely contributes to the reduced immunogenicity for heterologous vaccines after LA-YF-Vax administration. Identification of specific immune mechanisms related to vaccines should contribute to understanding of the "off-target," beneficial effects of live vaccines.

AAV Immunotoxicity: Implications in Anti-HBV Gene Therapy

Hepatitis B virus (HBV) has afflicted humankind for decades and there is still no treatment that can clear the infection. The development of recombinant adeno-associated virus (rAAV)-based gene therapy for HBV infection has become important in recent years and research has made exciting leaps. Initial studies, mainly using mouse models, showed that rAAVs are non-toxic and induce minimal immune responses. However, several later studies demonstrated rAAV toxicity, which is inextricably associated with immunogenicity. This is a major setback for the progression of rAAV-based therapies toward clinical application. Research aimed at understanding the mechanisms behind rAAV immunity and toxicity has contributed significantly to the inception of approaches to overcoming these challenges. The target tissue, the features of the vector, and the vector dose are some of the determinants of AAV toxicity, with the latter being associated with the most severe adverse events. This review discusses our current understanding of rAAV immunogenicity, toxicity, and approaches to overcoming these hurdles. How this information and current knowledge about HBV biology and immunity can be harnessed in the efforts to design safe and effective anti-HBV rAAVs is discussed.

How does diabetes type 1 affects immune response to hepatitis B virus vaccine in pediatric population? Evaluation of a booster dose in unresponsive subjects with type 1 diabetes

BACKGROUND

Hepatitis B virus (HBV) vaccine reduced the incidence of Hepatitis B worldwide. Genetic variability, by the presence of specific haplotypes of HLA system (HLA-DR3, HLA-DR4), influences the response to the vaccination. Subjects affected by type 1 diabetes (T1D), contrary to non-diabetics, have a high prevalence of Hepatitis B.

METHODS

The objective of the study was to evaluate anti-HBs antigen (anti-HBsAg) antibody (Ab) in a group of 201 children (age range: 2-18 years), regularly vaccinated against HBV according to the national vaccination schedule. Patients with anti-HBs Ab≥10 mIU/mL have been defined "responders" and those with anti-HBs Ab<10mIU/mL have been defined "non-responders." The possible association between the T1D and a low immune response to the vaccine has been subsequently valued. Besides the presence of T1D, other possible influential variables have been studied: sex, age, presence of celiac disease and Hashimoto's thyroiditis, intervening years from the diagnosis of diabetes and presence/absence of diabetic ketoacidosis at time of diagnosis.

RESULTS

Among the 201 subjects with T1D, 90 (44.8%) were responders, while 111 (55.2%) were non-responders; among the 145 subjects without T1D, 86 (59.3%) were responders and 59 (40.7%) non-responders. We invited "Subjects with T1D non-responders" to undergo a booster dose of the same vaccine. Of these, 21 refused the booster, reducing the sample to 90 patients. After 4 weeks from the booster dose 81 patients showed seroconversion ("false non-responders"), and 9 did not ("true non-responders").

CONCLUSIONS

After the booster dose, immune response in our cross-section has been similar to general population. Given the high frequency of "false non-responders" anti-HBsAg Ab should be tested in T1D patients and a booster dose should be administrated in non-responders.

Cured HCV patients with suboptimal hepatitis B vaccine response exhibit high self-reactive immune signatures

BACKGROUND AND RATIONALE

Chronic HCV infection induces lasting effects on the immune system despite viral clearance. It is unclear whether certain immune alterations are associated with vaccine responses in cured HCV patients.

APPROACH

Thirteen cured HCV patients received the standard 3-dose hepatitis B vaccine and were followed up at the 0, 1st, 6th, and 7th months (M0, M1, M6, and M7) after the first dose of vaccination. Thirty-three-color and 26-color spectral flow cytometry panels were used for high-dimensional immunophenotyping of the T-cell and B-cell subsets, respectively.

RESULTS

Compared to the healthy controls (HC), 17 of 43 (39.5%) immune cell subsets showed abnormal frequencies in cured HCV patients. Patients with cured HCV were further divided into high responders (HR, n = 6) and nonresponders (NR1, n = 7) based on the levels of hepatitis B surface antibodies at M1. Alterations in cell populations were more significant in NR1. Moreover, we found that high levels of self-reactive immune signatures, including Tregs, TD/CD8, IgD-only memory B, and autoantibodies, were associated with suboptimal hepatitis B vaccine responses.

CONCLUSIONS

Our data suggest that cured HCV patients exhibit persistent perturbations in the adaptive immune system, among which highly self-reactive immune signatures may contribute to a suboptimal hepatitis B vaccine response.

Vaccination in liver diseases and liver Transplantation: Recommendations, implications and opportunities in the post-covid era

The interest in vaccination efficacy and toxicity has surged following the Covid-19 pandemic. Immune responses to several vaccines have been shown to be suboptimal in patients with chronic liver disease (CLD) or post-liver transplant (LT), as a consequence of cirrhosis-associated immune dysfunction (CAID) or post-LT immunosuppression respectively. Accordingly, vaccine-preventable infections may be more common or severe than in the general population. The Covid-19 pandemic has greatly accelerated research and development into vaccination technology and platforms, which will have spillover benefits for liver patients. The aims of this review are: (i) to discuss the impact of vaccine-preventable infections on CLD and post-LT patients, (ii) to appraise current evidence supporting vaccination strategies, and (iii) to provide some insight into recent developments relevant for liver patients.

Impaired long-term anti-HBs responses in choronic hepatitis C patients: Results from a five-year follow-up study with healthy control

Although hepatitis B virus (HBV) vaccination is recommended for hepatitis C virus (HCV)-infected individuals to avoid HBV superinfection, the persistence of their humoral and cell-mediated immunity responses to HBV vaccination is still under investigation. Patients with chronic hepatitis C (CHC) and matched healthy controls, who completed three doses of hepatitis B vaccine (HepB) in 2014, were followed up five years later. One booster dose of HepB was given to those with antibody against hepatitis B surface antigen (anti-HBs) lower than 10mIU/mL. Anti-HBs was tested at follow-up and on the 14th day after the booster dose, as well as HBsAg specific spot-forming cells of interferon γ and interleukin (IL) 2, 4, 5, and 6. At five years, only 56.58% of the CHC patients had sero-protective titers (≥10mIU/mL) of anti-HBs, compared to 70.83% in the controls (P < .05). Similarly, the geometric mean concentration (GMC) of anti-HBs in CHC patients was significantly lower than that in controls (16.95 vs 37.34 mIU/mL, P < .05). After the booster, both GMC and the rate of anamnestic response increased to a very high level in the two groups and the difference between them disappeared (P > .05). Multivariable analysis showed that HCV infection was an independent predictor factor to anti-HBs level at follow-up. HBsAg specific IL-6 was stronger in the CHC patients compared to the controls (P < .05). The data indicate that the durability of protective anti-HBs is poorer in CHC patients compared to healthy individuals, and impaired long-term anti-HBs responses might be associated with the increased HBsAg specific IL-6 responses.

Efficacy of Hepatitis B Virus Vaccines HBVaxpro40© and Fendrix© in Patients with Chronic Liver Disease in Clinical Practice

Chronic liver disease results in a low response rate to the hepatitis B virus vaccine. Information on the efficacy of the double adjuvanted vaccine FENDRIX® (3-O-desacyl-4'-monophosphoryl lipid A and aluminum phosphate) and single adjuvant HBVAXPRO®40 (aluminum hydroxyphosphate sulfate) in chronic liver disease is scarce. The primary aim of this prospective study in clinical practice was to evaluate the effectiveness of HBVAXPRO®40 and FENDRIX® in this setting. Patients received HBVAXPRO® (0, 1 and 6 months) or FENDRIX® (0, 1, 2 and 6 months) depending on availability. Clinical data and anti-HBs levels were collected at 2, 6 and 12 months. A total of 125 patients were included (mean age 61.8 years; 57.6% males; 43.2% liver cirrhosis; 75.9% Child A and 24.1% Child B): 76 were vaccinated with HBVAXPRO® and 49 with FENDRIX®. There were no significant differences between the two vaccines. The overall response rates at 2, 6 and 12 months were 76.8, 72.8 and 59.2%, respectively. In the univariate analysis, active alcohol intake, alcohol etiology, liver cirrhosis and ultrasound signs of portal hypertension were associated with a lower response to vaccination, whereas in the multivariate analysis, liver cirrhosis was the only factor that significantly increased the likelihood of nonresponse (OR 10.5). HBVAXPRO® and FENDRIX® are good options for HBV vaccination in patients with chronic liver disease.

Hepatitis B vaccine coverage and risk factors for lack of vaccination in subjects with HBsAg negative liver cirrhosis in Italy: still, much work should be done

BACKGROUND

in Italy, Hepatitis-B-vaccine is advised and provided free-of-charge for subjects with chronic liver disease (CLD), including liver cirrhosis.

AIMS

to evaluate HB-vaccine-coverage and variables associated with lack of vaccination in cirrhotic patients with particular attention to cirrhosis' etiology.

METHODS

cirrhotic patients of any etiology (excluding HBsAg+) referring to 8 tertiary-centers were prospectively enrolled for a-six-months-period in 2019. Subjects were asked if they received HB-vaccine previously. Multiple-logistic-regression-analysis was performed to identify independent predictors of lack of vaccination.

RESULTS

731 cases were recruited. Overall-vaccine-coverage was 16.3% (23.7% in those younger than 65y, 10.0% in those older than 64y; p<0.001). Lack of information was the most frequent reason (78.5% of cases) reported by the 608 unvaccinated subjects, without statistical difference by area-of-birth (77.3% in Italians, 80.0% in people-born-abroad). Age>64 y (OR: 4.27; CI 95%: 2.52-7.24), educational level<9 years (OR: 3.52; CI 95%: 2.10-5.90), residence in South/Sardinia (OR 2.52; CI 95%:1.45-4.39), birth-abroad (OR 5.09; CI 95%: 1.07-24-.17), and Child grade B/C(OR 2.68; CI 95%: 1.35-5.33) all resulted independent predictors of likelihood of lack of vaccination.

CONCLUSIONS

Vaccination-rate in cirrhotic patients results very low. Vaccine-coverage implementation in these subjects, is warranted. Vaccine should be provided in early CLD, when immunization is most effective.

Single-cell transcriptomic analyses of T cells in chronic HCV-infected patients dominated by DAA-induced interferon signaling changes

Chronic infection with HCV is manifested by dysregulation of innate immune responses and impaired T cell function at multiple levels. These changes may impact susceptibility to other infections, responsiveness to antiviral therapies, vaccine responsiveness, and development of complications such as hepatocellular carcinoma. Highly effective direct-acting antiviral (DAA) therapy has revolutionized the management of chronic HCV, with expected cure rates exceeding 95%. DAA treatment represents a unique opportunity to investigate to what extent elimination of viral replication and chronic antigen stimulation can restore immunologic phenotype. In this study we interrogated the global transcriptional profile of isolated peripheral blood T cells before, during and after IFN-free DAA therapy using single-cell mRNA sequencing. Our results demonstrate that T cells mapped at single-cell resolution have dramatic transcriptomic changes early after initiation of DAA and many of these changes are sustained after completion of DAA therapy. Specifically, we see a significant reduction in transcripts associated with innate immune activation and interferon signaling such as ISG15, ISG20, IFIT3, OAS and MX1 in many different T cell subsets. Furthermore, we find an early upregulation of a gene involved in suppression of immune activation, DUSP1, in circulating T cells. Conclusion: This study provides the first in-depth transcriptomic analysis at the single-cell level of patients undergoing DAA therapy, demonstrating that IFN-free antiviral therapy in chronic HCV infection induces hitherto unrecognized shifts in innate immune and interferon signaling within T cell populations early, during, and long-term after treatment. The present study provides a rich data source to explore the effects of DAA treatment on bulk T cells.

Effectiveness of hepatitis B vaccination in chronic HCV patients after successful generic direct acting antiviral therapy: significance of isolated hepatitis B core antibodies

OBJECTIVE

Previous reports show conflicting results regarding hepatitis B virus (HBV) vaccine efficacy in Hepatitis C virus (HCV) infected individuals and in those with isolated hepatitis B core antibodies (HBcAb). We aimed to evaluate the effectiveness of HBV vaccine and identify possible factors that may contribute to hyporesponsivness in HCV-treated patients, including those with isolated HBcAb.

METHODS

We conducted a prospective study with 118 enrolled chronic HCV patients who followed a 12-week regimen of direct acting antivirals (DAAs) and were evaluated for HBV serological markers. Eventually, 98 received appropriate HBV vaccination and were assessed for response.

RESULTS

A total of 57.1% were vaccine responders although only 5.1% achieved a seroprotective level of HBsAb titre. The response rate was significantly lower among treated HCV patients with isolated HBcAb [2 (5.6%) vs. 40 (64.5%) respectively]. On multivariate analysis, advanced age [OR (95% CI) = 1.09 (1.02-1.17)] and presence of isolated HbcAb [OR (95% CI) = 39.59 (7.98-196.63)] were predictors of vaccine non-response. In our cost-effectiveness models, the cost of HBV serological screening was less than the nationally adopted non-screening approach. A model ratifying reinforced vaccination in non-responder HBcAb seropositive HCV patients would incur extra cost.

CONCLUSION

Hyporesponsiveness to the HBV vaccination is frequent in chronic HCV patients even after achieving SVR following DAAs. Although there is no consensus on the clinical management of patients with isolated HBcAb, our cost-effectiveness options may support decision-making for better clinical benefit and proper health investments.

In vitro transcribed mRNA for expression of designer nucleases: Advantages as a novel therapeutic for the management of chronic HBV infection

Chronic infection with the hepatitis B virus (HBV) remains a significant worldwide medical problem. While diseases caused by HIV infection, tuberculosis and malaria are on the decline, new cases of chronic hepatitis B are on the rise. Because often fatal complications of cirrhosis and hepatocellular carcinoma are associated with chronic hepatitis B, the need for a cure is as urgent as ever. Currently licensed therapeutics fail to eradicate the virus and this is attributable to persistence of the viral replication intermediate comprising covalently closed circular DNA (cccDNA). Elimination or inactivation of the viral cccDNA is thus a goal of research aimed at hepatitis B cure. The ability to engineer nucleases that are capable of specific cleavage of a DNA sequence now provides the means to disable cccDNA permanently. The scientific literature is replete with many examples of using designer zinc finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs) and RNA-guided endonucleases (RGENs) to inactivate HBV. However, important concerns about safety, dose control and efficient delivery need to be addressed before the technology is employed in a clinical setting. Use of in vitro transcribed mRNA to express therapeutic gene editors goes some way to overcoming these concerns. The labile nature of RNA limits off-target effects and enables dose control. Compatibility with hepatotropic non-viral vectors is convenient for the large scale preparation that will be required for advancing gene editing as a mode of curing chronic hepatitis B.

Chronic genotype 1 hepatitis C along with cirrhosis drives a persistent imprint in virus-specific CD8+ T cells after direct-acting antiviral therapies

Chronic hepatitis C virus (HCV) infection impairs HCV CD8⁺ T-cell responses, while it could influence immune responses towards unrelated viruses/vaccines (e.g. cytomegalovirus, CMV, and influenza, Flu). The aim of our study was to delineate whether restoration of these virus-specific CD8⁺ T cells occurs after direct-acting antiviral (DAA) therapies and particularly in patients with cirrhosis. We performed longitudinal analysis (baseline, week 4, follow-up [FU] 12 and FU48) of virus-specific CD8⁺ T cells by multicolour flow cytometry in HCV-cirrhotic patients undergoing DAA therapy (n = 26) after in vitro expansion with immunodominant HCV, CMV and Flu epitopes restricted by HLA-A*02. HCV noncirrhotic patients (n = 9) and healthy individuals (n = 10) served as controls. We found that the proliferative capacity of HCV-specific CD8⁺ T cells increased from baseline up to FU48 in a significant proportion of cirrhotic and noncirrhotic patients. Nevertheless, these cells remained poor cytokine producers in both patient groups, regardless of the down-regulation of inhibitory co-regulatory receptors in HCV-cirrhotic patients at FU48. Likewise, high expression levels of these exhaustion markers were detected in CMV-/Flu-specific CD8⁺ T cells in HCV-cirrhotic patients at all time points, albeit without affecting their proliferative capacity or cytokine production. We conclude that DAA therapies induce restoration of the proliferative capacity of HCV-specific CD8⁺ T cells. However, these cells remain phenotypically and functionally impaired. Contrarily, the 'exhausted' phenotype in CMV-/Flu-specific CD8⁺ T cells in HCV-cirrhotic patients did not associate with their functions. Larger studier with longer follow-up may elucidate whether this complex interplay influences the outcome of cirrhotic patients.

Response to hepatitis B virus vaccination in individuals with chronic hepatitis C virus infection

BACKGROUND

Previous reports show conflicting results regarding hepatitis B virus (HBV) vaccine efficacy in Hepatitis C virus (HCV)-infected individuals.

AIMS

To evaluate HBV-vaccine response and identify possible factors that may contribute to lower vaccine efficacy in patients infected with HCV.

METHODS

We retrospectively evaluated all patients with chronic HCV infection at Hennepin County Medical Center, in Minneapolis, Minnesota, between 2002 and 2018. We addressed laboratory, liver-related, virus-related as well as vaccine-related variables, and their association to HBV vaccine response. Differences were tested using either a Chi-squared test or a T test to compare means between the two populations. Multivariate regression was modeled as a logistic regression.

RESULTS

1506 patients were evaluated, of which 525 received appropriate HBV vaccination and were assessed for response. Among those, 79% were vaccine responders and 21% were non-responders. On multivariate analysis, cirrhosis was associated with lower response to the vaccine (OR 0.6, CI 0.44-0.94). We found no significant differences for vaccine response in relation to smoking (87% vs 86%), IV drug abuse (74% vs 72%), Diabetes Mellitus (26% vs 22%) being on hemodialysis (2% vs.5%), or virus related variables.

CONCLUSION

HCV infection seems to impair HBV vaccine response, with cirrhosis being the only identifiable risk factor for hypo-responsiveness among studied clinical and virus-related variables.

Vaccination in adult liver transplantation candidates and recipients

In patients with chronic liver disease and liver transplant recipients, cirrhosis-associated immune dysfunction syndrome and immunosuppressant drug regimens required to prevent graft rejection lead to a high risk of severe infections, associated with acute liver decompensation, graft loss and increased mortality. In addition to maintain their global health status, vaccination represents a major preventive measure against specific infectious risks of particular concern in this population, such as invasive pneumococcal diseases, influenza or viral hepatitis A and B. However, immunization in this setting raises several issues: i) recommended vaccination schedules rely on sparse immunogenicity data without clinical efficacy and effectiveness trials designed for this specific population; ii) dynamics of immunosuppression makes timing of immunization challenging; iii) live attenuated vaccines are contraindicated after transplantation; and iv) vaccines tolerance is poorly known in cirrhotic patients. This review outlines the rational for vaccination in adult liver transplant candidates and recipients and available data regarding immunization in this specific population.

NEW IMMUNIZATION SCHEDULE EFFECTIVENESS AGAINST HEPATITIS B IN LIVER TRANSPLANTATION PATIENTS

BACKGROUND

Although liver transplantation is considered to be a high-risk procedure, it is well-established as a treatment option for the cure and quality of life enhancement for individuals who suffer from diseases. Preventing an infection by hepatitis B virus through immunization schedules has been the most effective way to reduce complications, since it decreases the number of people who suffer from chronic hepatitis caused by the hepatitis B virus and eradicates its transmission.

OBJECTIVE

1. Analyzing evidence in the literature on various schedules employed for immunization against hepatitis B in patients who have received a liver transplantation. 2. Suggesting potential immunization schedules against hepatitis B in patients who suffer from liver cirrhosis, without previous verifying documentation, using the Child-Turcotte Pugh score, according to evidences found in the literature.

METHODS

Systematic review of the literature, conducted on the data bases MedLine, PubMed, and Lilacs, between September, 2017 and January, 2018, by using the following keywords: "Liver Transplantation, "Immunization Schedule", "Hepatitis B Vaccines". In order to analyze the articles, a summary figure was especially designed and both the results and discussion were presented in a descriptive way.

RESULTS

We included 24 studies; among them, eight had accelerated immunization schedules, 13 followed the conventional schedules, and three had super accelerated schedules. Regarding immunization, 21 studies were conducted with patients in the pre-transplant period, one with a transplanted patient, one with a pre-transplant group, and one with a post-transplant group. Found articles suggest that, disregarding the chosen immunization schedule, seroconversion rates tended to be lower as the liver disease advanced, compared to the healthy population.

CONCLUSION

The studies did not find seroconversion superiority between the different immunization schedules (conventional and unconventional). However, since candidates to liver transplantation are usually very vulnerable, results show that super accelerated immunization schedules are possibly recommended for such group of patients; serologic test results will be higher when the immunization schedule is completed in the pre-transplant period.

Direct-Acting Antiviral Treatment of HCV Infection Does Not Resolve the Dysfunction of Circulating CD8+ T-Cells in Advanced Liver Disease

Chronic hepatitis C virus (HCV) infection disrupts immune functions, including that of cytotoxic CD8⁺ T-cells which are important mediators of immune response. While HCV cure aims to eliminate long term sequelae of infection, whether direct-acting antiviral (DAA) treatment results in immune reconstitution remains unclear. We and others have reported generalized CD8⁺ T-cell dysfunction in chronic HCV infection and our research suggests that the degree of liver damage is a factor in this process. Our recent research indicates that liver fibrosis is not readily reversed after DAA-mediated clearance of chronic HCV infection. We therefore examined the function of circulating CD8⁺ T-cell subsets in chronic HCV infection in the context of liver fibrosis severity, determined by ultrasound elastography and Metavir F-score system. We observed progressive shifts in CD8⁺ T-cell subset distribution in HCV-infected individuals with advanced liver fibrosis (F4) compared to minimal fibrosis (F0-1) or uninfected controls, and this remained unchanged after viral cure. Impaired CD8⁺ T-cell function was observed as a reduced proportion of CD107⁺ and perforin⁺ late effector memory cells in HCV⁺(F4) and HCV⁺(F0-1) individuals, respectively. In HCV⁺(F4) individuals, nearly all CD8⁺ T-cell subsets had an elevated proportion of perforin⁺ cells while naïve cells had increased proportions of IFN-γ⁺ and CD107⁺ cells. These exaggerated CD8⁺ T-cell activities were not resolved when evaluated 24 weeks after completion of DAA therapy and HCV clearance. This was further supported by sustained, high levels of cell proliferation and cytolytic activity. Furthermore, DAA therapy had no effect on elevated concentrations of systemic inflammatory cytokines and decreased levels of inhibitory TGF-β in the plasma of HCV⁺(F4) individuals, suggesting HCV infection and advanced liver disease result in a long-lasting immune activating microenvironment. These data demonstrate that in chronic HCV infection, liver fibrosis severity is associated with generalized hyperfunctional CD8⁺ T-cells, particularly with perforin production and cytotoxicity, and this persists after viral clearance. Whether DAA therapy will eliminate other related long-term sequelae in HCV⁺(F4) individuals remains an important research question.

Immune response to hepatitis B vaccine in patients with chronic hepatitis C infection: A systematic review and meta-analysis

Hepatitis B virus and hepatitis C virus (HCV) co-infection can add to the severity of hepatitis and the risks of liver cirrhosis and hepatocellular carcinoma. Whether chronic HCV infection decreases antibody response to hepatitis B vaccination is still controversial. We evaluate the influence of HCV infection on antibody response to hepatitis B vaccination by a systematic review of published works with a meta-analysis of clinical trials. The random-effects model of DerSimonian and Laird with heterogeneity and sensitivity analyses were used in this study. The end-point of interest was the rate of patients showing seroconversion of antibody responses at completion of hepatitis B vaccination schedule among patients with chronic HCV infection versus healthy controls. We identified 11 studies involving 704 patients with HCV and 812 controls. Our results show a significant decrease in antibody seroconversion rates among patients with HCV versus healthy controls (pooled odds ratio = 0.17 [95% confidence interval, 0.11-0.28]). The P-value was 0.21 for our test of study heterogeneity. Stratified analysis in subgroups of interest and sensitivity analysis did not meaningfully change our results. Our meta-analysis showed patients with hepatitis C infection have a statistically significant lower rate of seroconversion in comparison to healthy controls, both in cirrhotic and non-cirrhotic patients. Chronic HCV infection can decrease the immune response to a standard schedule of hepatitis B vaccination. Further studies are needed to investigate the optimum vaccination schedule for patients with chronic HCV infection.

Pre-vaccine plasma levels of soluble inflammatory indices negatively predict responses to HAV, HBV, and tetanus vaccines in HCV and HIV infection

BACKGROUND

Chronic hepatitis C virus (HCV) and HIV infections are associated with impaired responses to neo-antigens contained in hepatitis A virus (HAV)/hepatitis B virus (HBV) vaccines, yet responsible mechanisms are unclear.

METHODS

ACTG 5232 and CFAR0910 were clinical trials where pre-vaccine levels of plasma IP10, IL-6, sCD163 and sCD14 were measured in viremic HCV- (n = 15) or HIV-infected participants (n = 24) and uninfected controls (n = 10). Accelerated dosing HAV/HBV vaccine and tetanus booster were administered and antibody response was measured at 0, 1, 3, 8, and 24 weeks.

RESULTS

Pre-vaccine plasma IP10, IL-6, and sCD14 levels were elevated in both HCV and HIV-infected participants, while sCD163 was also elevated in HCV-infected participants. Pre-immunization tetanus antibody levels were lower in HIV-infected than in uninfected participants, while vaccine induced antibody responses were intact in HCV and HIV-infected participants. After HAV/HBV vaccination, HCV and HIV-infected participants had lower and less durable HAV and HBV antibody responses than uninfected controls. Among HCV-infected participants, pre-vaccine plasma IP10, IL-6, sCD14, and sCD163 levels inversely correlated with HAV, HBV and tetanus antibody responses after vaccine. Low HAV/HBV vaccine responses in HIV-infected participants prohibited assessment of immune correlates.

CONCLUSIONS

During HCV and HIV infection markers of systemic inflammation reflect immune dysfunction as demonstrated by poor response to HAV/HBV neo-antigen vaccine.

Robust Antibody and Cytokine Response to Hepatitis B Vaccine Among Not-in-Treatment Patients With Chronic Hepatitis C: An Open-Label Control Study in China

Background

Hepatitis B vaccine is an effective measure to prevent hepatitis B virus infection. Whether chronic hepatitis C virus (HCV) infection decreases humoral and cell-mediated immunity responses to hepatitis B vaccination is still controversial.

Methods

Patients with chronic HCV infection who were not in treatment and healthy controls, matched at a 1:2 ratio for community, sex, and age (within 5 years), were identified from a community-based screening. All participants received 3 doses of hepatitis B vaccine. Antibody to hepatitis B surface antigen was tested 1 month after the third vaccine dose and was compared between 2 groups. Spot-forming cells (SFCs) of interferon γ and interleukin 2, 4, 5, and 6 were counted by means of enzyme-linked immunospot, and SFC counts were compared between the 2 groups.

Results

The rates of nonresponse and low, normal, and high response were 3.80%, 10.13%, 45.57%, and 40.50% respectively, in the HCV group, and the corresponding rates in the healthy control group were 1.26%, 10.13%, 39.24%, and 49.37% (all P > .05). There were no significant differences in SFC counts between the 2 groups for interferon γ or interleukin 2, 4, or 5 (all P > .05).

Conclusions

This study provided preliminary evidence of the good immunogenicity and safety of hepatitis B vaccination among patients in China with chronic hepatitis C who are not in treatment.

Clinical Trials Registration

NCT 02898922.

Immune response to hepatitis B vaccination in HIV-positive individuals with isolated antibodies against hepatitis B core antigen: Results of a prospective Italian study

BACKGROUND AND AIM

Antibodies against hepatitis B core antigen (anti-HBc) are found in 14-44% of patients with HIV infection, but it is still unclear whether hepatitis B virus (HBV) vaccination should be recommended for HIV-positive subjects with isolated anti-HBc (IAHBc). We examined the rate of anamnestic and primary responses (ARs and PRs) and associated factors in a group of HIV-infected patients with an IAHBc profile.

METHODS

This prospective study recruited 25 HIV-positive patients with anti-HBc alone who were vaccinated against HBV infection. Those without an AR (anti-hepatitis B envelope antigen [anti-HBs] levels of <10 U/L) or who were hypo-responsiveness (anti-HBs levels of >10 but <100 U/L) four weeks after the first dose of vaccine underwent a full course of vaccinations. Their clinical and virological data, including the presence of occult hepatitis B infection (OBI), were evaluated in accordance with the vaccination schedule.

RESULTS

Six of the 25 patients (24%) showed an AR, four of whom had anti-HBs levels of <100 U/L. Ten of 19 (52.6%) remaining patients became seroprotected after the third dose. OBI was detected in four of the six patients with an AR, two of the 10 patients with a PR, and none of the nine patients who did not respond. Multivariate analysis showed that an AR was associated with the presence of OBI (P = 0.0162), and a PR was associated with HCV antibody status. (P = 0.0191).

CONCLUSIONS

Our data suggest that testing for anti-HBc alone may not be a reliable means of assessing protection from HBV infection in HIV-positive patients. OBI-positive patients may benefit from a single vaccine dose. Anti-HCV serostatus may affect PRs.

HBV/HCV dual infection impacts viral load, antibody response, and cytokine expression differently from HBV or HCV single infection

Hepatitis B virus/hepatitis C virus (HBV/HCV) dual infection is common among high-risk individuals. To characterize the virological and immunological features of patients with HBV/HCV dual infection, we enrolled 1,049 individuals who have been identified as injection drug users. Patients were divided into single and dual infection groups according to the serological markers. We found the average HCV RNA level was significantly lower; however, HBV viral load was significantly higher in HBV/HCV dual-infected patients (n = 42) comparing HCV single infection (n = 340) or HBV single infection (n = 136). The level of anti-HBs in patients who experienced spontaneous HBV clearance was higher than that in HCV single-infected patients with HBV spontaneous clearance. The level of anti-HCV E2 in HBV/HCV dual infection was lower than that detected in HCV single infection. Serum levels of IL-6, IL-8, and TNF-α were significantly lower in HBV/HCV dual-infected patients than in patients infected with HBV or HCV alone. Taken together, two viral replications are imbalanced in dual infected patients. The anti-HBs and anti-HCV E2 antibody production were impaired and proinflammatory IL-6, IL-8, and TNF-α also downregulated due to dual infection. These findings will help further understanding the pathogenesis of HBV/HCV dual infection.

Vaccination against hepatitis B virus among people who inject drugs - A 20year experience from a Swedish needle exchange program

BACKGROUND

People who inject drugs (PWID) are at particular risk of hepatitis B virus (HBV) acquisition, but often have poor access or adherence to HBV vaccination. Vaccination against HBV has been offered at a major Swedish needle exchange program (NEP) since 1994. The aim of this study was to evaluate vaccine completion and response rates, and the effect of sequential booster doses to non-responders to the standard vaccination schedule.

METHODS

PWID enrolled in the NEP 1994-2013, without serological markers for HBV at baseline (negative for HBsAg/anti-HBc/anti-HBs), were offered a three-dose standard intramuscular vaccination schedule (Engerix®-B, GSK, 20μg/mL, intended to be received at months 0, 1 and 6). Vaccination response was defined as protective levels of anti-HBs (⩾10mIU/mL). Up to three booster doses were then offered for non-responders, each followed by anti-HBs testing.

RESULTS

HBV data was available for 2352 identifiable individuals at NEP enrolment, of whom 1516 (64.5%) had no markers for previous HBV exposure or vaccination. Vaccination was initiated for 1142 (75.3%) individuals and 898 (59.2%) completed the standard vaccination schedule. Post-vaccination anti-HBs levels were available from 800 individuals, with 598 (74.8%) responding to the basic vaccination schedule. After up to three booster doses a total of 676 (84.5%) individuals achieved protective anti-HBs levels. Non-response to vaccination was associated with higher age and anti-HCV positivity (p<0.001). Eighteen incident cases of HBV infection were observed among vaccine non-responders, as well as 30 cases among those who had not completed vaccination.

CONCLUSION

We demonstrate the feasibility of including HBV vaccination in the services offered by a NEP, with completion of vaccination in a majority of HBV-susceptible PWID. The response to HBV vaccination among PWID was relatively low; however, the addition of up to three booster doses improved the response rate from 74.8 to 84.5%.

Memory re-differentiation and reduced lymphocyte activation in chronic HCV-infected patients receiving direct-acting antivirals

Recently, the treatment of HCV has advanced significantly due to the introduction of direct-acting antivirals (DAAs). Studies using interferon (IFN)-containing regimens failed to consistently show restoration of immunologic responses. Therefore, IFN-free DAA formulations provide a unique opportunity to dissect the immunologic effect of HCV cure. This study investigates the restoration of the immune compartment as a consequence of rapid viral clearance in patients successfully treated with DAAs and in the absence of IFN and ribavirin. Here, we evaluate the immunologic changes that occurred following DAA-mediated HCV cure. Peripheral blood from nineteen previously treatment-naïve patients with chronic HCV genotype 1a/1b who received an IFN and ribavirin-free regimen of daclatasvir, asunaprevir and BMS-791325 was evaluated. Immune reconstitution occurs in patients in whom HCV was successfully eradicated via DAA therapy. Restoration of the CD4(+) T-cell compartment in the peripheral blood and a re-differentiation of the T lymphocyte memory compartment resulted in a more effector memory cell population and a reduction in expression in the co-inhibitory molecule TIGIT in bulk T lymphocytes. Furthermore, we observed a partial reversal of the exhausted phenotype in HCV-specific CD8(+) T cells and a dampening of the activation state in peripheral NK cells. Collectively, our data provide the groundwork for dissecting the effect of DAA therapy on the immune system and identifying novel mechanisms by which chronic HCV infection exerts immunosuppressive effects on T cells through the recently described co-inhibitory molecule TIGIT.

Recent advances in vaccination of non-responders to standard dose hepatitis B virus vaccine

Hepatitis B virus (HBV) infection is a global health problem. It is estimated there are more than 2 billion individuals exposed to the virus and 250 million are chronically infected. Hepatitis B is the cause of more than 600000 annual deaths due to cirrhosis and hepatocellular carcinoma. An effective vaccine exists and preventative initiatives center around universal vaccination especially in those at highest risk. Effective vaccination algorithms have led to a significant decline in the development of new infections and its devastating consequences. The vaccine is administered intramuscularly in three doses, with 95% showing long lasting serologic immunity. An additional fourth dose or a repeated higher dose three course regimen is given to those that fail to show immunity. Despite these additional regimens, some remain vulnerable to hepatitis B and are deemed non-responders. Individuals with chronic disease states such as kidney disease, liver disease, diabetes mellitus, as well as those with a genetic predisposition, and those on immunomodulation therapy, have the highest likelihood of non-response. Various strategies have been developed to elicit an immune response in these individuals. These include increased vaccination dose, intradermal administration, alternative adjuvants, alternative routes of administration, co-administration with other vaccines, and other novel therapies. These alternative strategies can show improved response and lasting immunity. In summary, HBV vaccination is a major advance of modern medicine and all individuals at risk should be sought and vaccinated with subsequent adequate titers demonstrated.

Recombinant HBV vaccine enhances the rate of sustained virological response when early initiated after anti-HCV combination therapy

The overall SVR rate for chronic hepatitis C genotype 4 using the Standard of care is 54.3%. HBV infection can be prevented by the administration of effective and safe vaccine. Evaluation of the vaccination-induced anti-HBs response rates in a cohort of HCV Egyptian patients after being exposed to antiviral combination therapy and the magnitude of its effect on the rate of SVR through its putative role in induction of crossed immunity. (A) 500 HCV patients who had completed the course of antiviral therapy and achieved ETR were retrospectively analyzed and received 20 μg of recombinant DNA vaccine for hepatitis B at time intervals (0, 1, and 4 months). The first dose of the vaccine was initiated one month post treatment. (B) Laboratory analysis: Included routine preliminary investigations to anti viral therapy and specific investigations as determination of anti-HBs antibodies 2 months following the third dose of vaccine. 433 patients showed protective response (86.6%), 67 patients were non-responders (13.4%) (P = 0.003). Adding HBV vaccine 1 month post-treatment increased SVR (400 patients, 80%) (χ(2)  = 40.3, P = 0.000). Diabetes affect response to HBV vaccine (P = 0.0001). Adding HBV vaccine to the post treatment care of patients with HCV after termination of antiviral therapy gain two benefits; protection from HBV and significant increase in rates of SVR.

Hepatitis B revaccination in HIV-infected vaccine non-responders: is double dosing always necessary?

Limited data exist on hepatitis B revaccination strategies for HIV-infected individuals who do not develop immunity after the first vaccination series. A retrospective cohort study was conducted to assess the immunogenicity of the second series of hepatitis B vaccine given in standard dosing (SD) and double dosing (DD) strategies among Thai HIV-infected adults during the period from January 2006 to December 2014. Of the 120 eligible patients, 68 (57%) were men, median age was 38 years old, 87 (73%) received SD and 33 (27%) received DD revaccination. The demographic and clinical characteristics of SD and DD groups were comparable. The overall vaccine response rate was significantly higher in DD group than SD group (97% vs. 70%; p = 0.001). Independent factors associated with no response to hepatitis B revaccination were receipt of SD vaccine (adjusted odds ratio [aOR] 16.04; p = 0.009), age ≥ 40 years (aOR 3.66; p = 0.009) and CD4 cell count at the time of revaccination less than 450 cells/µL (aOR 2.96; p = 0.04). These findings suggest that DD hepatitis B revaccination series should be given in HIV-infected patients who were at least 40 years old or had CD4 counts less than 450 cells/µL after no response to the first vaccination series.

New approaches in hepatitis B vaccination for celiac disease

Celiac disease (CD) is a gluten-induced immune-mediated disorder that has been associated with a defective response to the hepatitis B virus (HBV) vaccination. This unresponsiveness could lead to a world health problem, because non-responder patients could represent a reservoir of HBV-susceptible people that will persist as healthy carriers, leading to the diffusion of the disease. This article presents a literature review of both intramuscular (IM) and intradermal (ID) routes for boosters in celiac patients. We used PubMed database and generated the odds ratio (OR) of the response on the basis of electronic searches of clinical trials. Although our results confirm the positive response of celiac patients to IM vaccination, the ID route seems to be better than the conventional one, since it could provide a saving in cost and a greater immunogenicity.

Type I Interferon Elevates Co-Regulatory Receptor Expression on CMV- and EBV-Specific CD8 T Cells in Chronic Hepatitis C

Hepatitis C virus (HCV) readily sets up persistence in a large fraction of infected hosts. Mounting epidemiological and immunological evidence suggest that HCV's persistence could influence immune responses toward unrelated pathogens and vaccines. Nonetheless, the fundamental contribution of the inflammatory milieu during persistent HCV infection in impacting immune cells specific for common pathogens such as CMV and EBV has not been fully studied. As the co-regulatory receptors PD-1, Tim-3, and 2B4 have all been shown to be vital in regulating CD8(+) T cell function, we assessed their expression on CMV/EBV-specific CD8(+) T cells from patients with chronic hepatitis C (CHC) and healthy controls ex vivo and upon stimulation with virus-specific peptides in vitro. Total and CMV/EBV-specific CD8(+) T cells expressing PD-1, Tim-3, and 2B4 were highly enriched in patients with CHC compared to healthy individuals ex vivo. In vitro peptide stimulation further potentiated the differential co-regulatory receptor expression of PD-1, Tim-3, and 2B4, which then culminated in an enhanced functionality of CMV/EBV-specific CD8(+) T cells in CHC patients. Comprehensively analyzing plasma cytokines between the two cohorts, we observed that not only was IFNα-2a dominant among 21 other inflammatory mediators elevated in CHC patients but it also correlated with PD-1 and Tim-3 expressions ex vivo. Importantly, IFNα-2a further caused upregulation of these markers upon in vitro peptide stimulation. Finally, we could prospectively study patients receiving novel IFN-free antiviral therapy. Here, we observed that treatment-induced clearance of HCV resulted in a partial reversion of the phenotype of CMV/EBV-specific CD8(+) T cells in patients with CHC. These data reveal an alteration of the plasma concentrations of IFNα-2a together with other inflammatory mediators during CHC, which appeared to pervasively influence co-regulatory receptor expression on CMV/EBV-specific CD8(+) T cells.

Long-term effectiveness of accelerated hepatitis B vaccination schedule in drug users

OBJECTIVES

We demonstrated the effectiveness of an accelerated hepatitis B vaccination schedule in drug users.

METHODS

We compared the long-term effectiveness of accelerated (0-1-2 months) and standard (0-1-6 months) hepatitis B vaccination schedules in preventing hepatitis B virus (HBV) infections and anti-hepatitis B (anti-HBs) antibody loss during 2-year follow-up in 707 drug users (HIV and HBV negative at enrollment and completed 3 vaccine doses) from February 2004 to October 2009.

RESULTS

Drug users in the accelerated schedule group had significantly lower HBV infection rates, but had a similar rate of anti-HBs antibody loss compared with the standard schedule group over 2 years of follow-up. No chronic HBV infections were observed. Hepatitis C positivity at enrollment and age younger than 40 years were independent risk factors for HBV infection and antibody loss, respectively.

CONCLUSIONS

An accelerated vaccination schedule was more preferable than a standard vaccination schedule in preventing HBV infections in drug users. To overcome the disadvantages of a standard vaccination schedule, an accelerated vaccination schedule should be considered in drug users with low adherence. Our study should be repeated in different cohorts to validate our findings and establish the role of an accelerated schedule in hepatitis B vaccination guidelines for drug users.

Immunogenicity of hepatitis B vaccine in patients with inflammatory bowel disease and the benefits of revaccination

BACKGROUND AND AIM

The vaccination against hepatitis B virus (HBV) is recommended in patients with inflammatory bowel disease (IBD). However, the response to this vaccine seems to be lower in IBD patients than in the general population. This study aims to evaluate the immunogenicity of the HBV vaccine in a cohort of patients with IBD, to associate factors with the response and to analyze the effects of a second schedule vaccination.

METHODS

We conducted a retrospective cohort study of adults with IBD, susceptible to HBV infection. All patients received a three-dose standard schedule of HBV vaccine. Non-responders were revaccinated with a second three-dose standard schedule. Adequate immunity to HBV was defined as antibodies against hepatitis B surface antigen (anti-HBs) ≥ 10 mIU/mL. Age, comorbidities, treatment, and other variables were collected.

RESULTS

One hundred seventy-two patients were included and received the first HBV vaccine schedule. Eighty-seven developed anti-HBs ≥ 10 mIU/mL (50.6%; 95% confidence interval [CI]: 42.9-58.3). From the non-responders, 53 were revaccinated and 28 showed an adequate serological response (52.8%; 95% CI: 38.6-66.7). Age older than 55 years (OR: 3.6; 95% CI: 1.3-10.2) and comorbidities (OR: 2.8; 95% CI: 1.1-7.1) were associated with suboptimal response. In the multivariate analysis, only age was a predictor of non-response (age higher than 55 years; OR: 3.9; 95% CI: 1.3-11.9) CONCLUSION: The response rate to the HBV vaccine is lower in patients with IBD compared with the general population, especially in those older than 55 years. Revaccination improved response rate by 50%.

Old and new adjuvants for hepatitis B vaccines

The safety and immunogenicity profiles of currently available recombinant hepatitis B vaccines are excellent. However, it remains a real challenge to induce protective immunity in the target groups that respond poorly or not at all to conventional vaccines. Ideally, a hepatitis B vaccine can be developed that conveys lifelong protection against infection rapidly after the injection of a single dose. Although this goal is far from being reached, important improvements have been made. Novel vaccine adjuvants have been developed that enhance the immunogenicity of recombinant hepatitis B vaccines while maintaining a good safety profile. The different adjuvants and adjuvant systems that are discussed herein have all been thoroughly evaluated in clinical trials and some have reached or are close to reach the market.

Hepatitis A and B immunity and vaccination in chronic hepatitis B and C patients in a large United States cohort

BACKGROUND

Hepatitis A and B vaccines are effective in preventing superinfection and sequelae in patients with chronic hepatitis B or C. We describe immunity and vaccination against hepatitis A and B in chronic hepatitis patients from the US Chronic Hepatitis Cohort Study.

METHODS

We identified chronic hepatitis B and C patients with healthcare utilization during 2006-2008 and 12 months of enrollment. We used electronic laboratory records to determine immunity and medical and billing records for vaccination history. Immunity against hepatitis A was defined by positive hepatitis A antibody or documented vaccination. Immunity against hepatitis B was defined as hepatitis B surface antibody level ≥10 mIU/mL or core antibody positive, or by documented vaccination.

RESULTS

Among 1635 chronic hepatitis B patients, 978 (59.8%) were immune or vaccinated against hepatitis A, 122 (7.5%) had negative hepatitis A antibody tests, and 535 (32.7%) had no testing or vaccination record. Among 5328 chronic hepatitis C patients, 2998 (56.3%) were immune or vaccinated against hepatitis A, 659 (12.4%) had negative hepatitis A antibody tests, and 1671 (31.4%) had no testing or vaccination record. Additionally, 3150 (59.1%) chronic hepatitis C patients were immune or vaccinated against hepatitis B, 1003 (18.8%) had a negative test result, and 1175 (22.1%) were neither tested for nor vaccinated against hepatitis B.

CONCLUSIONS

Approximately 40% of chronic hepatitis B and C patients are susceptible to or have no documented immunity or vaccination against hepatitis A or hepatitis B. Clinicians should consider antibody testing and vaccination for this vulnerable population.

Out-of-sequence signal 3 as a mechanism for virus-induced immune suppression of CD8 T cell responses

Virus infections are known to induce a transient state of immune suppression often associated with an inhibition of T cell proliferation in response to mitogen or cognate-antigen stimulation. Recently, virus-induced immune suppression has been linked to responses to type 1 interferon (IFN), a signal 3 cytokine that normally can augment the proliferation and differentiation of T cells exposed to antigen (signal 1) and co-stimulation (signal 2). However, pre-exposure of CD8 T cells to IFN-inducers such as viruses or poly(I∶C) prior to antigen signaling is inhibitory, indicating that the timing of IFN exposure is of essence. We show here that CD8 T cells pretreated with poly(I∶C) down-regulated the IFN receptor, up-regulated suppressor of cytokine signaling 1 (SOCS1), and were refractory to IFNβ-induced signal transducers and activators of transcription (STAT) phosphorylation. When exposed to a viral infection, these CD8 T cells behaved more like 2-signal than 3-signal T cells, showing defects in short lived effector cell differentiation, reduced effector function, delayed cell division, and reduced levels of survival proteins. This suggests that IFN-pretreated CD8 T cells are unable to receive the positive effects that type 1 IFN provides as a signal 3 cytokine when delivered later in the signaling process. This desensitization mechanism may partially explain why vaccines function poorly in virus-infected individuals.

Testing for hepatitis B virus and HIV in patients with chronic hepatitis C: screening performance and outcome

BACKGROUND

Patients infected with hepatitis C virus (HCV) and co-infected with hepatitis B virus (HBV) and/or human immunodeficiency virus (HIV) are at increased risk for progression of liver disease. The aim of this study was to assess HBV and HIV screening performance and outcome in HCV patients followed at a Danish university hospital and affiliated regional outpatient clinics.

METHODS

HBV and HIV serology data were extracted from a quality assurance database for the assessment of screening performance in patients diagnosed with chronic HCV infection during the period 1 January 1996 to 31 December 2011. Patients with incomplete and missing serology data had complementary serology tests performed to assess the prevalence of HBV and HIV co-infection and HBV immune status.

RESULTS

Among 624 HCV patients, 10 (2%) were co-infected with chronic HBV and 32 (5%) with HIV. Approximately half of the cohort were non-immune to HBV or had an unknown HBV serology status. Serology results consistent with resolved infection and HBV vaccination were found in 209 (33%) and 65 (10%) patients, respectively. During the 16-y observation period, HBV and HIV screening coverage at HCV diagnosis increased from 23% to 92% and from 38% to 80%, respectively.

CONCLUSION

Despite improvements throughout the study period, HBV and HIV serology screening remained incomplete. The majority of patients were either HBV non-immune or had an unknown HBV serology status. These findings thus call for a more proactive screening approach as well as an improved HBV vaccination strategy for patients with chronic HCV infection.

Hepatitis B vaccine by intradermal route in non responder patients: An update

Vaccination is the main prophylactic measure to reduce the mortality caused by hepatitis B virus (HBV) infection in healthy subjects since the immune response to hepatitis B recombinant vaccination occurs in over 90% of general population. Individuals who develop an anti-HBs titer less than 10 mIU/mL after primary vaccination cycle are defined “no responders”. Many factors could cause a non response to the HBV vaccination, such as administration of the vaccine in buttocks, impaired vaccine storage conditions, drug abuse, smoking, infections and obesity. Moreover there are some diseases, like chronic kidney disease, human immunodeficiency virus infection, chronic liver disease, celiac disease, thalassaemia, type I diabetes mellitus, down’s syndrome and other forms of mental retardation that are characterized by a poorer response to HBV vaccination than healthy subjects. To date it is still unclear how to treat this group of patients at high risk of hepatitis B infection. Recent studies seem to indicate that the administration of HBV recombinant vaccine by the intradermal route is very effective and could represent a more useful strategy than intramuscular route. This review focuses on the use of anti hepatitis B vaccine by intradermal route as alternative to conventional intramuscular vaccine in all non responder patients. A comprehensive review of the literature using PubMed database, with appropriate terms, was undertaken for articles in English published since 1983. The literature search was undertaken in September 2013.

Management of infections in cirrhotic patients: report of a consensus conference

The statements produced by the consensus conference on infection in end-stage liver disease promoted by the Italian Association for the Study of the Liver, are here reported. The topics of epidemiology, risk factors, diagnosis, prophylaxis, and treatment of infections in patient with compensated and decompensated liver cirrhosis were reviewed by a scientific board of experts who proposed 26 statements that were graded according to level of evidence and strength of recommendation, and approved by an independent jury. Each topic was explored focusing on the more relevant clinical questions. By systematic literature search of available evidence, comparison and discussion of expert opinions, pertinent statements answering specific questions were presented and approved. Short comments were added to explain the basis for grading evidence particularly on case of controversial areas.

Safety and efficacy of hepatitis B vaccination in cirrhosis of liver

Introduction. Patients with chronic liver disease (CLD) are more likely to have severe morbidity and fatality rate due to superimposed acute or chronic hepatitis B (HBV) infection. The literature has shown that hepatitis B vaccines are safe and effective in patients with CLD, but the data in cirrhosis liver is lacking. We assessed the safety and immunogenicity of HBV vaccine in patients with cirrhosis liver. Methods. CTP classes A and B CLD patients negative for hepatitis B surface antigen and antibody to hepatitis B core antigen were included. All patients received three doses of hepatitis B vaccine 20 mcg intramuscularly at 0, 30, and 60 days. Anti-HBs antibody was measured after 120 days. Results. 52 patients with mean age 47.48 ± 9.37 years were studied. Response rates in CTP classes A and B were 88% and 33.3%. We observed that the alcoholic chronic liver disease had less antibody response (44%) than other causes of chronic liver disease such as cryptogenic 69% and HCV 75%. Conclusions. Patients with cirrhosis liver will have low antibody hepatitis B titers compared to general population. As the age and liver disease progress, the response rate for hepatitis B vaccination will still remain to be weaker.

Immunogenecity of hepatitis A and B vaccination in pediatric patients with inflammatory bowel disease

OBJECTIVES

Aim of the study was to evaluate the response to hepatitis A and B vaccination in pediatric patients with inflammatory bowel disease (IBD).

METHODS

A total of 47 patients with IBD (25 ulcerative colitis, 14 Crohn's disease, and 8 indeterminate colitis) ages 3 to 17 years were compared with 50 healthy age- and sex-matched controls. Screening for hepatitis A and B serology was carried out before vaccination. Susceptible cases received 20 mg of recombinant DNA vaccine for hepatitis B (0, 1, and 6 months)and 720 milliELISA units of inactivated hepatitis A virus vaccine (HAV) (0 and 6 months). Postvaccination serologic evaluation was performed 1 month after the last dose of primary vaccination, 1 month after the booster dose, and once every year during follow-up.

RESULTS

A total of 23 patients and 35 controls received HAV and protective anti-HAV antibodies were developed in all of the patients and controls (P =1.00). Forty-seven patients and 50 controls received hepatitis B vaccine and 70.2% of the patients versus 90% of the controls achieved seroprotection(anti-HBs titers 10 mIU/mL) 1 month after primary vaccination (95% confidence interval 0.71–0.87, P = 0.02). The overall seroprotection rates were 96% in controls and 85.1% in patients after the whole hepatitis B vaccination series (95% confidence interval 0.83–0.95, P = 0.08). No significant reduction was observed in antibody response among patients and controls during the follow-up period.

CONCLUSIONS

The rate of seroconversion to the hepatitis B vaccine was lower in pediatric patients with IBD than in healthy controls and hepatitis A vaccine was highly immunogenic among patients with IBD.

Response to hepatitis A and B vaccination in pediatric patients with celiac disease

OBJECTIVES

The aim of the study was to evaluate the response to hepatitis A and B vaccinations in pediatric patients with celiac disease (CD).

METHODS

Thirty patients with CD ages 1 to 15 years were compared with 50 healthy age-, sex-, and body mass index-matched controls. Screening for hepatitis A and B serology was carried out before vaccination. Susceptible cases received 20 μg of recombinant DNA vaccine for hepatitis B (0,1, and 6 months) and 720 milliELISA units of inactivated hepatitis A virus (HAV) vaccine (0 and 6 months). Postvaccination serologic evaluation was performed 1 month after the last dose of primary vaccination, 1 month after the booster dose, and once every year during follow-up.

RESULTS

Sixteen patients and 35 controls received hepatitis A vaccine; protective anti-HAV antibodies were developed in 12 (75%) of the patients and all of the controls (75% vs 100%, respectively; 95% confidence interval [CI] 0.47-0.92, P=0.007). Thirty patients and 50 controls received hepatitis B vaccine, and 70% of the patients vs 90% of the controls achieved seroprotection (anti-HBs titers ≥10 mIU/mL) 1 month after primary vaccination (95% CI 0.74-0.90, P=0.03). Four patients were unresponsive to both of the vaccines. The overall seroprotection rates were 96% in controls and 80% in patients after the whole hepatitis B vaccination series (95% CI 0.04-0.18, P=0.04). No significant reduction was observed in antibody response among patients and controls during follow-up period.

CONCLUSIONS

The rate of seroconversion to the hepatitis B virus- and HAV vaccine is lower in patients with CD than in healthy controls.

Chronic bystander infections and immunity to unrelated antigens

Chronic infections with persistent pathogens such as helminths, mycobacteria, Plasmodium, and hepatitis viruses affect more than a third of the human population and are associated with increased susceptibility to other pathogens as well as reduced vaccine efficacy. Although these observations suggest an impact of chronic infections in modulating immunity to unrelated antigens, little is known regarding the underlying mechanisms. Here, we summarize evidence of the most prevalent infections affecting immunity to unrelated pathogens and vaccines, and discuss potential mechanisms of how different bystander chronic infections might impact immune responses. We suggest that bystander chronic infections affect different stages of host responses and may impact transmission and recognition of other pathogens, innate immune responses, priming and differentiation of adaptive effector responses, as well as the development and maintenance of immunological memory. Further understanding of the immunological effects of coinfection should provide opportunities to enhance vaccine efficacy and control of infectious diseases.

Response to hepatitis A and B vaccination in patients with chronic hepatitis C: 8-year follow-up

BACKGROUND

In patients with chronic hepatitis C (CHC), superinfection with hepatitis A (HAV) or B (HAB) viruses is associated with increased morbidity and mortality. The seroconversion rate of these patients following vaccination is considered to be lower than in healthy subjects.

AIM

To evaluate the response to HAV and HBV vaccination in children with CHC.

METHODS

Thirty patients with CHC aged from 7.3 to 18 years were compared with 50 healthy age-, gender- and body-mass-index-matched controls. Post-vaccination serological evaluation was performed 1 month after the last dose of primary vaccination, 1 month after the booster dose and once a year during follow-up.

RESULTS

Twenty-two patients received hepatitis A vaccine and response rate was 95.4%. Thirty patients received hepatitis B vaccine and 80% responded (hepatitis Bs titres ≥10 mIU/ml). Thirty-five controls received hepatitis A vaccine and protective anti-HAV antibodies developed in all. All of the controls were vaccinated against hepatitis B virus and 90% responded. After the whole vaccination series, overall seroprotection rates were 86% in patients and 96% in controls. No significant reduction in antibody response was observed in patients or controls during 8-years follow-up.

CONCLUSIONS

The rate of seroconversion to the HBV vaccine is lower in patients with CHC than in healthy controls but response to HAV is adequate.

Tim-3 pathway controls regulatory and effector T cell balance during hepatitis C virus infection

Hepatitis C virus (HCV) is remarkable at disrupting human immunity to establish chronic infection. Upregulation of inhibitory signaling pathways (such as T cell Ig and mucin domain protein-3 [Tim-3]) and accumulation of regulatory T cells (Tregs) play pivotal roles in suppressing antiviral effector T cell (Teff) responses that are essential for viral clearance. Although the Tim-3 pathway has been shown to negatively regulate Teffs, its role in regulating Foxp3(+) Tregs is poorly explored. In this study, we investigated whether and how the Tim-3 pathway alters Foxp3(+) Treg development and function in patients with chronic HCV infection. We found that Tim-3 was upregulated, not only on IL-2-producing CD4(+)CD25(+)Foxp3(-) Teffs, but also on CD4(+)CD25(+)Foxp3(+) Tregs, which accumulate in the peripheral blood of chronically HCV-infected individuals when compared with healthy subjects. Tim-3 expression on Foxp3(+) Tregs positively correlated with expression of the proliferation marker Ki67 on Tregs, but it was inversely associated with proliferation of IL-2-producing Teffs. Moreover, Foxp3(+) Tregs were found to be more resistant to, and Foxp3(-) Teffs more sensitive to, TCR activation-induced cell apoptosis, which was reversible by blocking Tim-3 signaling. Consistent with its role in T cell proliferation and apoptosis, blockade of Tim-3 on CD4(+)CD25(+) T cells promoted expansion of Teffs more substantially than Tregs through improving STAT-5 signaling, thus correcting the imbalance of Foxp3(+) Tregs/Foxp3(-) Teffs that was induced by HCV infection. Taken together, the Tim-3 pathway appears to control Treg and Teff balance through altering cell proliferation and apoptosis during HCV infection.

Efficacy of high-dose intra-dermal hepatitis B virus vaccine in previous vaccination non-responders with chronic liver disease

BACKGROUND

Hepatitis B virus (HBV) vaccination is essential in chronic liver disease (CLD), because it can help prevent acute-on-chronic disease, which has potentially fatal complications. Unfortunately, this group has a significant proportion of HBV vaccination non-responders. A variety of intra-muscular (IM) vaccination methods have been used in an attempt to remedy this poor-response, but with limited success.

AIMS

Herein is reported the safety and efficacy of high-dose intra-dermal (ID) HBV vaccination in CLD individuals who had failed previous IM standard and boost-dosing regimens.

METHODS

Forty-eight CLD individuals, known HBcAb negative, who had failed both a three-dose schedule of 40 μg IM vaccination, and boost dosing of either 40 or 80 μg IM, were identified, of which 42 completed the vaccination course. Each received a 40 μg ID total dose (20 μg per arm) during their clinic visits until a response was documented or a maximum of three doses had been administered. HBsAb titer ≥ 10 mIU/ml was regarded as an immunologic response; the intention was to achieve an optimum response of ≥ 100 mIU/ml.

RESULTS

Twenty-nine of forty-two (69%) individuals had an immunologic response, with 15 (51%) of the responders having the optimum response. No changes in serologic data occurred. No serious dermatologic reactions were observed. No differences between those who responded and those who did not were observed with regard to the presence of cirrhosis, diabetes mellitus, or chronic kidney disease.

CONCLUSIONS

High-dose ID HBV vaccination of previous CLD non-responders to the standard IM regimen with boost dosing is both safe and efficacious, and should be considered for all such groups.

Changes in hepatitis A and B vaccination rates in adult patients with chronic liver diseases and diabetes in the U.S. population

Professional societies recommend hepatitis A and hepatitis B immunization for individuals with chronic liver disease (CLD), but the degree of implementation is unknown. Data were obtained from the National Health and Nutrition Examination Surveys (NHANES) conducted in 1999-2008. For the entire study population and for those with CLD and diabetes, we determined the rates and independent predictors of history of hepatitis A and hepatitis B (HepA and HepB) vaccinations, of their effectiveness, and of seroprevalence of hepatitis A antibody and anti-HB surface antibody. In total, 24,871 participants from NHANES were included: 14,886 (1999-2004) and 9,985 (2005-2008). Of these individuals, 14.0% had CLD and 8.6% had diabetes. During the study period, HepA vaccination in CLD increased from 13.3% ± 1.0% to 20.0% ± 1.5%, HepB vaccination increased from 23.4% ± 1.2% to 32.1% ± 1.5%. Of subtypes of CLD, HepA vaccination rates increased only in nonalcoholic fatty liver disease (NAFLD), whereas HepB vaccination increased for patients with hepatitis C and nonalcoholic fatty liver disease. In the diabetic cohort, HepA vaccination rates increased from 9.3% ± 1.1% to 15.4% ± 1.7% and HepB rates increased from 15.2% ± 1.5% to 22.4% ± 1.7%. All changes were similar to those observed in the general population. The quality measure (QM) for HepA in the general population decreased from 44.4% ± 1.2% in 1999-2004 to 41.7% ± 1.9% in 2005-2008, and similar changes were noted for all subcohorts. On the other hand, QM for HepB increased from 31.7% ± 0.9% to 40.7% ± 1.0% in the population, whereas no changes in QM were noted in any diagnostic cohort except for NAFLD.

CONCLUSIONS

Although vaccination rates in CLD and diabetic cohorts are increasing, they remain low. Given the public health implications of acute hepatitis A and hepatitis B in patients with CLD, better implementation of the vaccination recommendations for these populations is warranted.