The Impact of Hepatitis B Virus Precore/Core Gene Carboxyl Terminal Mutations on Viral Biosynthesis and the Host Immune Response

Hepatitis B virus (HBV) infection is a major health problem with an important biological and a significant socio-economic impact all over the world. There is a high pressure to come up with a new and more efficient strategy against HBV infection, especially after the recent success of HCV treatment. Preventing HBV infection through vaccine is currently the most efficient way to decrease HBV-related cirrhosis and liver cancer incidence, as well as the best way to suppress the HBV reservoir. The vaccine is safe and efficient in 80-95% of cases. One of its most important roles is to reduce materno-fetal transmission, by giving the first dose of vaccine in the first 24 hours after birth. Transmission of HBV infection early in life is still frequent, especially in countries with high endemicity.Successful HBV clearance by the host is immune-mediated, with a complex combined innate and adaptive cellular and humoral immune response. Different factors, such as the quantity and the sequence of HBV epitope during processing by dendritic cells and presenting by different HLA molecules or the polymorphism of T cell receptors (TOL) are part of a complex network which influences the final response. A new potential therapeutic strategy is to restore T-cell antiviral function and to improve innate and adaptive immune response by immunotherapeutic manipulation.It appears that HBV eradication is far from being completed in the next decades, and a new strategy against HBV infection must be considered. Abbreviations: ALT: alanine aminotransferase; APC: antigen presenting cells; cccDNA: covalently closed circular DNA; HBIG: hepatitis B immunoglobulin; HbsAg: hepatitis B surface antigen; HBV: hepatitis B virus; HCC: hepatocellular carcinoma; CTL: cytotoxic T lymphocyte; IFN: interferon; NUC: nucleos(t)ide analogues; pg RNA: pre genomic RNA; TLR: toll-like receptors; TOL: T cell receptors.

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Hepatitis B virus (HBV) viral load, liver and renal function in adults treated with tenofovir disoproxil fumarate (TDF) vs. untreated: a retrospective longitudinal UK cohort study

BMC Infectious Diseases ◽

10.1186/s12879-021-06226-0 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Tingyan Wang ◽

David A. Smith ◽

Cori Campbell ◽

Jolynne Mokaya ◽

Oliver Freeman ◽

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Keyword(s):

Viral Load ◽

Hepatitis B Virus ◽

Hepatitis B ◽

Renal Impairment ◽

Clinical Guidelines ◽

Untreated Group ◽

Liver Inflammation ◽

B Virus ◽

The Impact

Abstract Background Current clinical guidelines recommend treating chronic hepatitis B virus (HBV) infection in a minority of cases, but there are relatively scarce data on evolution or progression of liver inflammation and fibrosis in cases of chronic HBV (CHB) that do not meet treatment criteria. We aimed to assess the impact of TDF on liver disease, and the risk of renal impairment in treated CHB patients in comparison to untreated patients. Methods We studied a longitudinal ethnically diverse CHB cohort in the UK attending out-patient clinics between 2005 and 2018. We examined TDF treatment (vs. untreated) as the main exposure, with HBV DNA viral load (VL), ALT, elastography scores and eGFR as the main outcomes, using paired tests and mixed effects model for longitudinal measurements. Additionally, decline of eGFR during follow-up was quantified within individuals by thresholds based on clinical guidelines. Baseline was defined as treatment initiation for TDF group and the beginning of clinical follow-up for untreated group respectively. Results We included 206 adults (60 on TDF, 146 untreated), with a median ± IQR follow-up duration of 3.3 ± 2.8 years. The TDF group was significantly older (median age 39 vs. 35 years, p = 0.004) and more likely to be male (63% vs. 47%, p = 0.04) compared to the untreated group. Baseline difference between TDF and untreated groups reflected treatment eligibility criteria. As expected, VL and ALT declined significantly over time in TDF-treated patients. Elastography scores normalised during treatment in the TDF group reflecting regression of inflammation and/or fibrosis. However, 6/81 (7.4%) of untreated patients had a progression of fibrosis stage from F0-F1 to F2 or F3. There was no evidence of difference in rates or incidence of renal impairment during follow-up in the TDF vs. untreated group. Conclusions Risk of liver inflammation and fibrosis may be raised in untreated patients compared to those receiving TDF, and TDF may benefit a larger percentage of the CHB population.

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Hepatitis B Virus Infection in Pregnancy: Immunological Response, Natural Course and Pregnancy Outcomes

Journal of Clinical Medicine ◽

10.3390/jcm10132926 ◽

2021 ◽

Vol 10 (13) ◽

pp. 2926

Author(s):

Sirinart Sirilert ◽

Theera Tongsong

Keyword(s):

Hepatitis B Virus ◽

Hepatitis B ◽

Pregnancy Outcomes ◽

Natural Course ◽

Hbv Infection ◽

Chronic Hbv Infection ◽

B Virus ◽

Chronic Hbv ◽

Adverse Pregnancy ◽

The Impact

This review aimed to provide an update on the impact of pregnancy on the natural course of hepatitis B virus (HBV) infection and also on the impact of HBV infection on adverse pregnancy outcomes, including mother-to-child transmission (MTCT). For the literature review, original research articles, review articles, and guidelines were narratively reviewed and comprehensively validated. The databases of PubMed, EMBASE, and CINAHL were carefully searched for articles in English on topics related to HBV infection, pregnancy, and vertical transmission from 1960 to May 2021. Immunological changes during pregnancy such as suppression of Th1 response and induction of Th2 immunity lead to an impaired immune reaction to HBV and stimulate viral activity along with the reduction of CD8 T cells to escape immune detection. The impact of pregnancy on the natural course of chronic HBV infection seems to be minimal, while pregnancy can increase morbidity and mortality in the case of advanced HBV hepatitis or cirrhosis. Importantly, hepatitis flare or alanine aminotransferase (ALT) flare can occur during pregnancy and is more common during the postpartum period due to the interaction between HBV and the immune response. Interestingly, the impact of HBV infection on adverse pregnancy outcomes is more serious than ever thought. Updated evidence indicates that pregnancies with chronic HBV infection increase the risk of preterm birth and gestational diabetes, especially in cases of positive hepatitis e antigen (HBeAg).

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