Association of HBsAg levels with differential gene expression in NK, CD8 T, and memory B cells in treated patients with chronic HBV.

Background & Aims: HBsAg secretion may impact immune responses to chronic HBV infection. Thus, therapeutic approaches to suppress HBsAg production are being investigated. Our study aims to examine the immunomodulatory effects of high and low levels of circulating HBsAg and thereby improve our understanding of anti-HBV immunity.

Validation and optimization of AFP-based biomarker panels for early HCC detection in Latin America and Europe.

Background: HCC is a major cause of cancer death worldwide. Serum biomarkers such as alpha-fetoprotein (AFP), protein induced by vitamin K absence-II, and the Gender, Age, AFP-L3, AFP, Des-gamma-carboxy prothrombin (GALAD) score have been recommended for HCC surveillance. However, inconsistent recommendations in international guidelines limit their clinical utility.

Single-cell RNA sequencing of liver fine-needle aspirates captures immune diversity in the blood and liver in chronic hepatitis B patients.

Background And Aims: HBV infection is restricted to the liver, where it drives exhaustion of virus-specific T and B cells and pathogenesis through dysregulation of intrahepatic immunity. Our understanding of liver-specific events related to viral control and liver damage has relied almost solely on animal models, and we lack useable peripheral biomarkers to quantify intrahepatic immune activation beyond cytokine measurement. Our objective was to overcome the practical obstacles of liver sampling using fine-needle aspiration and develop an optimized workflow to comprehensively compare the blood and liver compartments within patients with chronic hepatitis B using single-cell RNA sequencing.

Treatment induced clearance of hepatitis E viruses by interferon-lambda in liver-humanized mice.

Background: Hepatitis E viruses (HEV) are an underestimated global cause of enterically transmitted viral hepatitis, which may persist in immunocompromised hosts, posing a risk for progressive liver fibrosis with limited treatment options. We previously established liver-humanized mice as a model for chronic HEV infections, which can be cleared by a 2-week pegylated (peg)-Interferon(IFN)α treatment course. However, severe side effects may hamper the use of IFNα in immunocompromised transplant recipient patients.

Sexual Dimorphism in Hepatocyte Xenograft Models.

Humanized liver mouse models are crucial tools in liver research, specifically in the fields of liver cell biology, viral hepatitis and drug metabolism. The livers of these humanized mouse models are repopulated by 3-dimensional islands of fully functional primary human hepatocytes (PHH), which are notoriously difficult to maintain in vitro. As low efficiency and high cost hamper widespread use, optimization is of great importance.

Differential gene expression, irrespective of circulating Hepatitis B Surface Antigen levels, between Inactive Carrier and Nucleos(t)ide Analogue-Treated Hepatitis B Virus patients.

Long-term viremia control in chronic HBV patients occurs either spontaneously in inactive carrier (IC) patients or therapy-induced by nucleos(t)ide analogues (NUC). To better understand the characteristics of viremia control, we evaluated gene expression in purified leukocyte subsets from IC versus NUC-treated patients, and evaluated the putative modulatory effects of hepatitis B surface antigen (HBsAg). We observed that gene expression in NUC-treated patients differed markedly from IC patients, especially in dendritic cells, monocytes, and CD8+ T cells, while serum HBsAg levels had little effect.

Validation of Whole Blood Rapid Diagnosis Test for Hepatitis B.

We recently published a report validating point-of-care rapid diagnostic tests (RDT) for the diagnosis of Hepatitis B virus (HBV) infection in serum. In the current report, we validated a whole-blood RDT for HBsAg in the form of a test-strip. The test was validated in 55 HBV positive individuals across all genotypes other than F, and in 20 HBV negative individuals in the Netherlands.

Evaluation of Rapid Diagnostic Tests for Assessment of Hepatitis B in Resource-Limited Settings.

Chronic Hepatitis B (HBV) is the most important cause of liver disease worldwide. There is a need for low-cost tests to aid in diagnosis and management of HBV infection in resource-limited settings. We evaluated the utility of several rapid diagnostic tests (RDT) in three different continents (Europe, South America, Africa).

Hepatitis B core-related antigen monitoring during peginterferon alfa treatment for HBeAg-negative chronic hepatitis B.

Serum Hepatitis B core-related antigen (HBcrAg) level moderately correlates with cccDNA. We examined whether HBcrAg can add value in monitoring the effect of peginterferon (PEG-IFN) therapy for HBeAg-negative chronic hepatitis B (CHB) infection. Thus, serum HBcrAg level was measured in 133 HBeAg-negative, mainly Caucasian CHB patients, treated with 48 weeks of PEG-IFN alfa-2a.

Relationship between hepatitis B core-related antigen levels and sustained HBeAg seroconversion in patients treated with nucleo(s)tide analogues.

Hepatitis B e antigen (HBeAg) seroconversion experienced during nucleo(s)tide analogue (NUC) therapy is often not sustained. We aimed to study whether hepatitis B core-related antigen (HBcrAg) levels predict sustained HBeAg seroconversion in patients treated with NUCs. We studied HBeAg-positive patients treated with NUCs for at least 6 months.

Validation of a point-of-care rapid diagnostic test for hepatitis C for use in resource-limited settings.

Background: Treatment of HCV with direct-acting antivirals has enabled the discussion of HCV eradication worldwide. Envisioning this aim requires implementation of mass screening in resource-limited areas, usually constrained by testing costs.

Methods: We validated a low-cost, rapid diagnosis test (RDT) for HCV in three different continents in 141 individuals.

Diagnostic and analytical performance of the hepatitis B core related antigen immunoassay in hepatitis B patients.

Background: Novel serological markers for Hepatitis B virus (HBV) infection are needed for prognosis and guidance of therapy.

Objective: We evaluated the diagnostic performance of the Fujirebio Lumipulse G HBcrAg immunoassay on the Fujirebio LUMIPULSE G1200 analyzer.

Study Design: Analytical performance was examined using three HBeAg positive HBV samples.

Gene expression profiling of human tissue-resident immune cells: Comparing blood and liver.

In this study, we describe a method to reliably characterize intrahepatic leukocyte populations using flow cytometry and next-generation RNA sequencing on fresh human liver biopsies. Over the last decades, immune responses of viral hepatitis patients, and of other liver diseases, have been incompletely characterized. Most studies include peripheral blood samples only, foregoing the possibility to investigate the site of inflammation directly.

Mucosal-Associated Invariant T Cells Are More Activated in Chronic Hepatitis B, but Not Depleted in Blood: Reversal by Antiviral Therapy.

Background: Mucosal-associated invariant T (MAIT) cells might play a role in control of viral replication during chronic hepatitis B (cHBV) infection, but little is known of their number, phenotype, or function in cHBV patients.

Methods: We performed flow cytometry on CD3+Vɑ7.2+CD161+ MAIT cells in blood of 55 cHBV patients.

Interferon-alpha treatment rapidly clears Hepatitis E virus infection in humanized mice.

Antiviral treatment options for chronic Hepatitis E Virus (HEV) infections are limited and immunological determinants of viral persistence remain largely unexplored. We studied the antiviral potency of pegylated interferon-α (pegIFNα) against HEV infections in humanized mice and modelled intrahepatic interferon stimulated gene (ISG) responses. Human gene expression levels in humanized mouse livers were analyzed by qPCR and Nanostring.

Mucosal-associated invariant T-cell frequency and function in blood and liver of HCV mono- and HCV/HIV co-infected patients with advanced fibrosis.

Background & Aims: Mucosal-associated invariant T (MAIT) cells are important innate T cells with antimicrobial and immunoregulatory activity, recently found to be depleted in blood of patients with HIV and HCV mono-infections. In this study, we assessed the impact of HIV, HCV and HCV/HIV co-infection on circulating and intrahepatic MAIT-cells and correlations with liver fibrosis.

Methods: In this cross-sectional study, nine healthy subjects, nine HIV, 20 HCV and 22 HCV/HIV co-infected patients were included.

NK cell phenotypic and functional shifts coincide with specific clinical phases in the natural history of chronic HBV infection.

Background: Chronic HBV infection can be divided into 4 distinct clinical phases: immune tolerant, immune active, inactive carrier, and HBeAg-negative hepatitis. Using a systems biology approach, we recently identified innate immune response components, specifically NK cells as a distinctive factor of specific HBV clinical phases. To expand on this study and identify the underlying immunological mechanisms, we performed a comprehensive profiling of NK cells in chronic HBV infection.

Frequencies of Circulating MAIT Cells Are Diminished in Chronic HCV, HIV and HCV/HIV Co-Infection and Do Not Recover during Therapy.

Objective: Mucosal-associated invariant T (MAIT) cells comprise a subpopulation of T cells that can be activated by bacterial products and cytokines to produce IFN-γ. Since little is known on MAIT cells during HCV infection, we compared their phenotype and function in comparison to HIV and HCV/HIV co-infected patients, and determined the effect of IFN-α-based and direct-acting antiviral therapy on MAIT cells of HCV patients.

Methods: Blood samples from patients with chronic HCV (CHCV), virologically suppressed HIV, acute HCV/HIV co-infection (AHCV/HIV) and healthy individuals were examined by flowcytometry for phenotype and function of MAIT and NK cells.

Similar frequencies, phenotype and activation status of intrahepatic NK cells in chronic HBV patients after long-term treatment with tenofovir disoproxil fumarate (TDF).

Background: Currently, much effort is directed at further improving treatment for chronic hepatitis B patients by assessing the effect of immunomodulatory agents during therapy with nucleotide analogues (NUC). Although there are some reports on the effect of NUC therapy on peripheral natural killer (NK) cells, no studies investigated the long-term effects of NUC treatment on intrahepatic NK cells of chronic HBV patients. We aimed to prospectively investigate cell frequencies, phenotype, and activation status of intrahepatic NK cells of CHB patients on prolonged treatment with TDF.

Longitudinal analysis of peripheral and intrahepatic NK cells in chronic HCV patients during antiviral therapy.

Introduction: A strong immune response is integral to the clearance of HCV infection. NK cells are specialized cells that are able to inhibit replication of HCV in infected hepatocytes. Previous studies have correlated therapy outcome in HCV to the expression of various markers on NK cells.

Immunological Analysis During Interferon-Free Therapy for Chronic Hepatitis C Virus Infection Reveals Modulation of the Natural Killer Cell Compartment.

Background: Chronic hepatitis C virus (HCV) infection is a global health problem, resulting in liver failure, hepatocellular carcinoma, and liver-related death. Natural killer (NK) cells are innate immune cells, and their activity is known to correlate to viral treatment response of HCV. In this study, we investigate the immune effects of viral load decline with direct-acting antivirals (DAAs) in blood.

Re-evaluation of hepatitis B virus clinical phases by systems biology identifies unappreciated roles for the innate immune response and B cells.

Unlabelled: To identify immunological mechanisms that govern distinct clinical phases of a chronic hepatitis B virus (HBV) infection-immune tolerant (IT), immune active (IA), inactive carrier (IC), and hepatitis B e antigen (HBeAg)-negative (ENEG) hepatitis phases-we performed a systems biology study. Serum samples from untreated chronic HBV patients (n = 71) were used for multiplex cytokine measurements, quantitative hepatitis B surface antigen (HBsAg), HBeAg levels, HBV genotype, and mutant analysis. Leukocytes were phenotyped using multicolor flow cytometry, and whole-blood transcriptome profiles were generated.

Gene expression profiling to predict and assess the consequences of therapy-induced virus eradication in chronic hepatitis C virus infection.

Unlabelled: Systems biology has proven to be a powerful tool to identify reliable predictors of treatment response in chronic hepatitis C virus (HCV) infection. In the present study, we studied patients with chronic HCV infection who responded to interferon (IFN)-based therapy, as evidenced by an absence of HCV RNA at the end of treatment, and focused on two issues that have not received much attention. First, we evaluated whether specific genes or gene expression patterns in blood were able to distinguish responder patients with a viral relapse from responder patients who remained virus negative after cessation of treatment.

Monocytes from chronic HBV patients react in vitro to HBsAg and TLR by producing cytokines irrespective of stage of disease.

Individuals who are chronically infected with the hepatitis B virus (HBV) are highly heterogeneous with respect to serum levels of HBV DNA, HBV particles and viral proteins. Since circulating leukocytes, such as monocytes, are constantly exposed to these viral components, it is likely that the functionality of these cells is affected. However, at present, little information is available on the consequences of the interaction between monocytes and viral components.

Intrahepatic natural killer cell activation, but not function, is associated with HBsAg levels in patients with HBeAg-negative chronic hepatitis B.

Background & Aims: Natural killer (NK) cells play an important role in the immune response to viruses. As the hepatitis B virus (HBV) replicates in hepatocytes, examination of the liver of chronic hepatitis B (CHB) patients is crucial to better understand the role of NK cells in HBV. HBeAg-negative CHB differs in many aspects from HBeAg-positive CHB, and until now little is known about the intrahepatic NK cell response in HBeAg-negative patients.