195 research outputs found
The elimination of hepatitis D as a public health problem: Needs and challenges
Epidemiology; Hepatitis D virus; Public healthEpidemiologÃa; Virus de la hepatitis D; Salud públicaEpidemiologia; Virus de l'hepatitis D; Salut PúblicaInfection with hepatitis D virus leads to liver disease and cancer most rapidly of all hepatitis viruses. However, knowledge about hepatitis D remains poor and the burden and impact are underestimated, even though some 12–15 million people mainly in low- and middle-income countries may be affected. Its epidemiology is changing, with increasing migration leading to increased risks of infection and disease. A recent Viral Hepatitis Prevention Board meeting reviewed the current epidemiological status, improvements in diagnostic testing, advances in the development of novel antiviral agents in phase III trials and the need for a greater public health response, such as new guidelines and recommended testing of all people newly identified as infected with hepatitis B virus for hepatitis D virus infection. It identified issues and needs for attention with regard to prevention, diagnosis and treatment.The VHPB is supported by unrestricted grants from the vaccine industry (GlaxoSmithKline Biologicals, Sanofi Pasteur, Merck and Gilead), but remains strict operational/scientific independence and editorial control. Speakers, neither board members are paid for their participation
Liver Monocytes and Kupffer Cells Remain Transcriptionally Distinct during Chronic Viral Infection
Due to the scarcity of immunocompetent animal models for chronic viral hepatitis, little is known about the role of the innate intrahepatic immune system during viral replication in the liver. These insights are however fundamental for the understanding of the inappropriate adaptive immune responses during the chronic phase of the infection. We apply the Lymphocytic Choriomenigitis Virus (LCMV) clone 13 mouse model to examine chronic virus-host interactions of Kupffer cells (KC) and infiltrating monocytes (IM) in an infected liver. LCMV infection induced overt clinical hepatitis, with rise in ALT and serum cytokines, and increased intrahepatic F4/80 expression. Despite ongoing viral replication, whole liver transcriptome showed baseline expression levels of inflammatory cytokines, interferons, and interferon induced genes during the chronic infection phase. Transcriptome analyses of sorted KC and IMs using NanoString technology revealed two unique phenotypes with only minimal overlap. At the chronic viral infection phase, KC showed no increased transcription of activation markers Cd80 and Cd86, but an increased expression of genes related to antigen presentation, whereas monocytes were more activated and expressed higher levels of Tnf transcripts. Although both KCs and intrahepatic IM share the surface markers F4/80 and CD11b, their transcriptomes point towards distinctive roles during virus-induced chronic hepatitis
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. Human CXCL10 was measured in mouse serum. HEV genotype 3 (gt3) infections were cleared from liver and feces within 8 pegIFNα doses in all mice and relapsed after a single pegIFNα injection in only half of treated animals. Rapid viral clearance by pegIFNα was confirmed in HEV gt1, but not in Hepatitis B Virus infected animals. No ISG induction was observed in untreated HEV gt3 and gt1 infected humanized livers compared to control chimeric mice, irrespective of the human hepatocyte donor, viral isolate or HEV infection duration. Human specific ISG transcript levels in mouse liver increased significantly after pegIFNα treatment and induced high circulating human CXCL10 in mouse serum. In conclusion, HEV gt1 and gt3 infections do not elicit innate intrahepatic immune responses and remain highly sensitive to pegIFNα in immunocompromised humanized mice
Unique intrahepatic transcriptomics profiles discriminate the clinical phases of a chronic HBV infection
Chronic hepatitis B is a highly heterogeneous liver disease characterized by phases with fluctuations in viral replication and progressive liver damage in some, but not all infected individuals. Despite four decades of research, insight into host determinants underlying these distinct clinical phases-immunotolerant, immune active, inactive carrier, and HBeAg-negative hepatitis±remains elusive. We performed an in-depth transcriptome analysis of archived FFPE liver biopsies of each clinical phase to address host determinants associated with the natural history. Therefore, we determined, for the first time, intrahepatic global expression profiles of well-characterized chronic HBV patients at different clinical phases. Our data, obtained by microarray, demonstrate that B cells and NK/cytotoxicrelated genes in the liver, including CD19, TNFRSF13C, GZMH, and KIR2DS3, were differentially expressed across the clinical HBV phases, which was confirmed by modular analysis and also Nanostring arrays in an independent cohort. Compared to the immunotolerant phase, 92 genes were differentially expressed in the liver during the immune active phase, 46 in the inactive carrier phase, and 71 in the HBeAg-negative phase. Furthermore, our study also revealed distinctive transcription of genes associated with cell cycle activity, NF-κB signaling, cytotoxic function and mitochondrial respiration between clinical phases. Our data define for the first time using microarray unique transcriptomes in the HBV-infected liver during consecutive clinical phases. We demonstrate that fluctuations of viral loads and liver damage coincide with fluctuations in the liver transcriptome and point to functionalimmune and non-immune-components contributing to the clinical phenotype in patients
DNGR1-mediated deletion of A20/Tnfaip3 in dendritic cells alters T and B-cell homeostasis and promotes autoimmune liver pathology
Dendritic cells (DCs) are central regulators of tolerance versus immunity. The outcome depends amongst others on DC subset and activation status. Whereas CD11b+ type 2 conventional DCs (cDC2s) initiate proinflammatory helper T (Th)-cell responses, CD103+ cDC1s are crucial for regulatory T-cell (Treg) induction and CD8+ T-cell activation. DC activation is controlled by the transcription factor NF-κB. Ablation of A20/Tnfaip3, a critical regulator of NF-κB activation, in DCs leads to constitutive DC activation and development of systemic autoimmunity. We hypothesized that the activation status of cDCs controls the development of autoimmunity.
To target cDCs, DNGR1(Clec9a)-cre-mediated excision of A20/Tnfaip3 was used through generation of Tnfaip3fl/flxClec9a+/cre (Tnfaip3DNGR1−KO) mice. Immune cell activation was evaluated at 31-weeks of age.
We found that DNGR1-cre-mediated deletion of A20/Tnfaip3 resulted in liver pathology characterized by inflammatory infiltrates adjacent to the portal triads. Both cDC subsets as well as monocyte-derived DCs (moDCs) in Tnfaip3DNGR1−KO livers harbored an activated phenotype. Specifically, the costimulatory molecule CD40 in liver cDCs and moDCs was regulated by A20/Tnfaip3 expression. Livers from Tnfaip3DNGR1−KO mice had augmented prop
Liver monocytes and kupffer cells remain transcriptionally distinct during chronic viral infection
Due to the scarcity of immunocompetent animal models for chronic viral hepatitis, little is known about the role of the innate intrahepatic immune system during viral replication in the liver. These insights are however fundamental for the understanding of the inappropriate adaptive immune responses during the chronic phase of the infection. We apply the Lymphocytic Choriomenigitis Virus (LCMV) clone 13 mouse model to examine chronic virus-host interactions of Kupffer cells (KC) and infiltrating monocytes (IM) in an infected liver. LCMV infection induced overt cli
Patient profiled data for treatment decision-making:valuable as an add-on to hepatitis C clinical guidelines?
Background and Aims: Systematic reviews and medical guidelines are widely used in clinical practice. However, these are often not up-to-date and focussed on the average patient. We therefore aimed to evaluate a guideline add-on, TherapySelector (TS), which is based on monthly updated data of all available high-quality studies, classified in specific patient profiles. Methods: We evaluated the TS for the treatment of hepatitis C (HCV) in an international cohort of patients treated with direct-acting antivirals between 2015 and 2020. The primary outcome was the number of patients receiving one of the two preferred treatment options of the HCV TS, based on the highest level of evidence, cure rate, absence of ribavirin-associated adverse effects, and treatment duration. Results: We enrolled 567 patients. The number of patients treated with one of the two preferred treatment options according to the HCV TS ranged between 27% (2015) and 60% (2020; p < 0.001). Most of the patients received a regimen with a longer treatment-duration (up to 34%) and/or addition of ribavirin (up to 14%). The effect on the expected cure-rate was minimal (1–6% higher) when the first preferred TherapySelector option was given compared to the actual treatment.Conclusions: Medical decision-making can be optimised by a guideline add-on; in HCV its use appears to minimise adverse effects and cost. The use of such an add-on might have a greater impact in diseases with suboptimal cure-rates, high costs or adverse effects, for which treatment options rely on specific patient characteristics.</p
Point-of-Care Tests for Hepatitis B Are Associated with A Higher Linkage to Care and Lower Cost Compared to Venepuncture Sampling During Outreach Screenings in an Asian Migrant Population
Background: This study compares venepuncture versus point-of-care (POC) HBsAg tests on screening cost and linkage to care in prospective outreach screenings in an Asian population in three major cities in Belgium between 10/2014 and 5/2018. Methods: Two community outreach screening programs were organised between 10/2014 and 5/2018. The first screening program used venepuncture and serologic testing for HBsAg. In the second program, HBsAg was tested in finger stick blood POC tests. Positive results were confirmed during outpatient visits with serologic testing. Linkage to care was defined as having received specialist care follow-up with at least one abdominal ultrasound within three months of screening. Results: For 575 participating individuals, 571 valid results were obtained, 456 with venepuncture, and 115 using POC testing. Overall HBsAg seroprevalence was 6.8%. Linkage to care was higher when using POC testing compared to venepuncture (86% or n = 6/7 versus 34% or n = 11/32; p = 0.020). The POC screening program was economically more attractive with a total cost of € 1,461.8 or € 12.7 per person screened compared to € 24,819 or € 54.0 per person screened when using venepuncture testing. Results and an appointment for specialist care follow-up were given onsite with POC testing, while with venepuncture testing; results were sent within 20-45 days. Conclusion: In an Asian migrant population in Belgium with an HBsAg seroprevalence of 6.8%, HBV screening based on POC tests resulted in lower costs per person screened (76.5% lower), and higher linkage to care (2.5 times)
Sorted B cell transcriptomes point towards actively regulated B cell responses during ongoing chronic hepatitis B infections
The natural course of chronic hepatitis B virus (HBV) infections follows distinct clinical disease phases, char-acterized by fluctuating levels of serum HBV DNA and ALT. The immune cells and their features that govern these clinical disease transitions remain unknown. In the current study, we performed RNA sequencing on pu-rified B cells from blood (n = 42) and liver (n = 10) of healthy controls and chronic HBV patients. We found distinct gene expression profiles between healthy controls and chronic HBV patients, as evidenced by 190 differentially expressed genes (DEG), but also between the clinical phenotypes of a chronic HBV infection (17?110 DEG between each phase). Numerous immune pathways, including the B cell receptor pathway were upregulated in liver B cells when compared to peripheral B cells. Further investigation of the detected DEG suggested an activation of B cells during HBeAg seroconversion and an active regulation of B cell signalling in the liver
- …