Host genetic factors affecting spontaneous HBsAg seroclearance in chronic hepatitis B patients

Anti-HBc: a significant host predictor of spontaneous HBsAg seroclearance in chronic hepatitis B patients - a retrospective longitudinal study

BACKGROUND AND AIM

In chronic hepatitis B infection (CHB), seroclearance of hepatitis B surface antigen (HBsAg) is associated with favourable clinical outcomes compared to those with persistent HBsAg seropositivity, and thus considered as a desired treatment endpoint. This current study explores the possibility of serum antibody to hepatitis B core antigen (anti-HBc) as a potential predictive factor of HBsAg seroclearance.

METHODS

This is a retrospective study that analyzed the plasma samples of CHB patients using the LUMIPULSE® G1200 analyzer. The longitudinal anti-HBc level between patients who subsequently achieved HBsAg seroclearance (S-losers) and those with persistent HBsAg-positivity (controls) were compared at multiple time points before the event.

RESULTS

A total of 240 subjects (120 S-losers and 120 controls; age- and gender-matched) were included (mean age 56.42 ± 10.81, 65% male). Compared to controls, S-losers had significantly lower plasma anti-HBc levels prior to HBsAg seroclearance, with a significant trend of declining plasma anti-HBc 8-5 years prior to HBsAg seroclearance (p < 0.01), while such trend was not observed in controls. ROC curve analysis revealed that plasma anti-HBc at multiple time points before HBsAg seroclearance return AUC greater than 0.7. Plasma anti-HBc level at the cut-off value of 82.50 COI was 68.3% sensitive and 90% specific for HBsAg seroclearance within 1 year. Combining with quantitative HBsAg < 100 IU/mL, anti-HBc < 82.5 COI identified 88.2% patients who would develop HBsAg seroclearance within 1 year.

CONCLUSION

Plasma anti-HBc level began to decline 10 years prior to HBsAg seroclearance and can serve as a potential predictor for subsequent HBsAg seroclearance.

High Prevalence of Hepatitis B Virus Infection Among People With HIV in Rural and Periurban Communities in Botswana

Background

We aimed to determine the prevalence of hepatitis B virus (HBV) infection among people with human immunodeficiency virus (PWH) in rural and periurban communities in Botswana.

Methods

PWH from a previous population-based study, the Botswana Prevention Combination Project, which enrolled adults in 30 communities across Botswana (2013-2018), were screened for HBV surface antigen (HBsAg) and HBV core antibody (anti-HBc). HBsAg-positive (HBsAg+) samples were further screened for HBV core immunoglobulin M antibodies (anti-HBc immunoglobulin M [IgM]) and HBV e antigen (HBeAg). We quantified HBV viral load on participants who tested positive (n = 148) and negative for HBsAg (n = 381).

Results

Of 3304 participants tested, 271 (8% [95% confidence interval {CI}, 7%-9%]) were HBsAg+ while 1788 (56% [95% CI, 54%-57%]) of 3218 PWH whom we tested had positive anti-HBc. Approximately 88% of HBsAg+ participants were on antiretroviral therapy (ART), 40% and 56% of whom were receiving lamivudine- and tenofovir-containing ART, respectively. Male sex (relative risk ratio [RRR], 1.8 [95% CI, 1.2-2.7]) and the northern geographic region (RRR, 2.5 [95% CI, 1.4-4.7]) were independent predictors of HBV infection (HBsAg+). Of 381 persons with negative HBsAg who were tested for occult HBV, 126 (33% [95% CI, 29%-38%]) had positive HBV DNA. Eleven participants were highly viremic with high HBV viral load while on a lamivudine- or tenofovir-containing regimen. Ten (91%) of these participants also had positive HBeAg serology, while 4 (36%) had positive anti-HBc IgM serology.

Conclusions

The prevalence of HBV was high among PWH in Botswana while on ART regimens with activity against HBV.

Possible association of HLA-DP polymorphism and antiretroviral therapy with hepatitis B virus clearance in an HIV-infected Vietnamese population

There is little evidence regarding the association between hepatitis B virus (HBV) chronicity and HLA-DP among the HIV-infected Vietnamese population. To study this, we conducted a cross-sectional analysis and a prospective study involving an HIV-infected Vietnamese cohort. The association between HBV chronicity and HLA-DP single nucleotide polymorphisms (SNPs) of rs3077 and rs9277535 among Vietnamese patients with previous HBV exposure was first evaluated. In addition, treatment-naive patients with chronic HBV infection were followed between 2012 and 2017 for HBV clearance after the initiation of antiretroviral therapy (ART). A total of 820 subjects with previous HBV exposure were included in the cross-sectional study. Among them, 147 (17.9 %) had chronic HBV infection, and 673 (82.1 %) achieved HBV clearance. The proportions of minor allele homozygotes of rs3077 and rs9277535 were 10.9 % and 15.2 % (p = 0.481) and 4.1 % and 11.7 % (p = 0.003), respectively. Multivariate analysis showed that rs9277535 minor homozygote was a significant protective factor against chronic HBV infection (odds ratio [OR], 0.271; 95 % confidence interval [CI]; 0.114-0.642, p = 0.001). Further, none of the 43 patients in the prospective study, who received ART possessed the rs9277535 minor homozygote. The average follow-up period was 4.8 years, and 10 subjects (23.3 %, 4.9 %/person-years) achieved HBV clearance. Univariate analysis revealed that the SNPs were not significantly associated with HBV clearance. In conclusion, our study confirmed that the rs9277535 minor allele homozygote was significantly associated with HBV clearance among HIV-infected Vietnamese patients.

Association of single nucleotide polymorphisms in immune-related genes with spontaneous HBsAg seroconversion: A systematic review and meta-analysis

BACKGROUND

Studies have reported that the immune system modulation genes are involved in the seroconversion during hepatitis B virus (HBV) infection. Here, a systematic review with meta-analysis is implemented on the association of polymorphisms in immune-related genes with the spontaneous hepatitis B surface antigen (HBsAg) seroconversion.

METHODS

A systematic literature search was conducted in the main electronic databases of Scopus, PubMed, and Web of Science before May 2022. Pooled odds ratio (OR) and their corresponding 95% confidence interval (CI) were used to evaluate the strength of the association between genetic polymorphisms and the chance of spontaneous HBsAg seroconversion.

RESULTS

A total of 40 studies finally included for meta-analysis of 2 HLA-DP SNPs, 2 HLA-DQ SNPs, 3 IFNL3/4 SNPs, 2 IL10 SNPs, and 5 TNF SNPs. Based on the overall pooled analysis, HLA-DP rs3077 A (OR = 1.47, 95%CI: 1.32-1.65), HLA-DP rs9277535 A (OR = 1.48, 95%CI: 1.32-1.66), HLA-DQ rs2856718 G (OR = 1.37, 95%CI: 1.18-1.59), HLA-DQ rs7453920 A (OR = 1.41, 95%CI: 1.04-1.93), IFNL3/4 rs12980275 G (OR = 1.26, 95%CI: 1.01-1.58), TNFA rs1799964 T (OR = 1.17, 95%CI: 1.02-1.35), and TNFA rs1800630 C (OR = 1.26, 95%CI: 1.03-1.55) increased significantly the chance of spontaneous HBsAg seroconversion.

CONCLUSION

This meta-analysis showed that the HLA-DP gene rs3077 and rs9277535 SNPs, HLA-DQ gene rs2856718 and rs7453920 SNPs, IFNL3/4 gene rs12980275 SNP, TNFA gene rs1799964 and rs1800630 SNPs are involved in the spontaneous HBsAg seroconversion.

Genetic polymorphisms in the IFNL4, MxA, and MxB genes were associated with biochemical index of chronic HBV patients from Yunnan, China

Hepatitis B virus (HBV) infection causes Hepatitis B, which is one of the most common causes of hepatocellular carcinoma (HCC). The single nucleotide polymorphisms (SNPs) of the host immune genes could impact HBV infection, viral clearance, and treatment effect. However, the contradictory roles of several studies suggest further analysis of various populations. The whole blood and biochemical indexes of 448 HBV patients and matched controls were collected from the Yunnan population to investigate the genetic roles of IFNL4 and the downstream genes (MxA and MxB). The genotypes, alleles, and haplotypes frequencies of the seven SNPs (rs11322783, rs117648444, rs2071430, rs17000900, rs9982944, rs408825, and rs2838029) from the HBV patients and controls were analyzed. However, no association was identified between the SNPs and HBV infection. Then, biochemical index levels were evaluated among the HBV patients with different genotypes of the seven SNPs. The results indicated that the liver function index levels (including alanine transaminase (ALT), aspartate transaminase (AST), total bilirubin (TBIL), direct bilirubin (DBIL), indirect bilirubin (IBIL), and albumin (ALB)) were influenced by the genotypes of the SNPs in HBV patients. Moreover, when the HBV patients were divided into HBsAg-positive and -negative groups, the association between the SNP genotypes and the biochemical indexes still existed. In addition, although the genetic polymorphisms in the IFNL4, MxA, and MxB genes were not significantly associated with HBV infection in the Yunnan population, these genes could indirectly influence disease progression by associating with the biochemical index levels of Yunnan HBV patients.

Hepatitis B virus infection and its determinants among HIV positive pregnant women: Multicenter unmatched case-control study

Background

Hepatitis B virus (HBV) kills millions of people globally; it is worse in pregnant women. HBV and Human Immune Virus (HIV) co-infection is associated with increased liver diseases such as cirrhosis and hepatocellular carcinoma. This study aimed at identifying the determinants of HBV infection among HIV-positive pregnant women.

Methods

A multicentre unmatched case-control study was conducted among 109 cases (HBV/HIV co-infected) and 327 controls (HIV positive) pregnant women in seven hospitals of the Eastern Amhara region. Interview and chart review data collection techniques were employed by trained personnel. A binary logistic regression model was used to identify independent predictors of hepatitis B virus infection. Variables with a p-value of <0.05 and 95% confidence interval for odds ratio not containing 1 considered independent predictors of HBV infection.

Results

The findings of this study revealed that history of STI [AOR, 1.97, 95%CI, 1.09–3.56], hospital admission [AOR, 3.08, 95%CI, 1.69–5.61], traditional delivery care [AOR, 3.31, 95%CI, 1.72–6.37], family history of HBV [AOR, 3.33, 95%CI, 1.72–6.37], presence of opportunistic infections [AOR, 0.23, 95%CI, 0.12–0.58], viral load [AOR, 7.58, 95%CI, 3.18–8.01], CD4 count [AOR, 2.15, 95% CI, 1.01–4.59], anaemia [AOR, 3.07, 95% CI, 1.71–5.51] and unsafe sex [AOR, 1.98, 95%CI, 1.09–3.61] had a statistically significant association with HBV infection.

Conclusions

Several exposure variables had statistically significant association with HBV infection. High Viral Load appeared to be the largest predictor of HBV infection in HIV patients. Therefore, targeted interventions such as behavioral change intervention for unsafe sex and STI should be in place, and screening tests and treatment at the early stage of conception for both partners is necessary.

Beyond Metabolism: Role of the Immune System in Hepatic Toxicity

The liver is primarily thought of as a metabolic organ; however, the liver is also an important mediator of immunological functions. Key perspectives on this emerging topic were presented in a symposium at the 2018 annual meeting of the American College of Toxicology entitled "Beyond metabolism: Role of the immune system in hepatic toxicity." Viral hepatitis is an important disease of the liver for which insufficient preventive vaccines exist. Host immune responses inadequately clear these viruses and often potentiate immunological inflammation that damages the liver. In addition, the liver is a key innate immune organ against bacterial infection. Hepatocytes and immune cells cooperatively control systemic and local bacterial infections. Conversely, bacterial infection can activate multiple types of immune cells and pathways to cause hepatocyte damage and liver injury. Finally, the immune system and specifically cytokines and drugs can interact in idiosyncratic drug-induced liver injury. This rare disease can result in a disease spectrum that ranges from mild to acute liver failure. The immune system plays a role in this disease spectrum.

Humoral Immune Responses and Hepatitis B Infection

BACKGROUND

Chronicity or seroclearance of hepatitis B virus (HBV) antigens is determined by the host immune responses. Current approaches to treat HBV patients are based on inhibition of replication using different antivirals (nucleoside or nucleotide analogs) as monotherapy, or along with immune modulators as combination therapy is being used worldwide for reducing the viral load. Understanding the role of immune cellular therapies with currently available treatments for persistent viral-mediated responses in HBV patients is unexplored. However, the generation of antibodies against a surface (HBs) and envelop (HBe) antigen of hepatitis B remains an issue for future studies and needs to be explored.

SUMMARY

Humoral immunity, specifically T follicular helper (TFh) cells, may serve as a target for therapy for HBsAg seroconversion. In this review, we have been engrossed in the importance and role of the humoral immune responses in CHBV infection and vertical transmission. Key Message: TFh cells have been suggested as the potential target of immunotherapy which lead to seroconversion of HBe and HBs antigens of HBV. HBsAg seroconversion and eradication of covalently closed circular DNA are the main challenges for existing and forthcoming therapies in HBV infection.

Single-nucleotide polymorphism of rs7944135 (macrophage-expressed gene 1) is associated with hepatitis B surface antigen seroclearance in chronic hepatitis B infection: A cohort study

Clearance of the hepatitis B surface antigen (HBsAg) is the ultimate aim of treatment for patients with chronic hepatitis B (CHB) infection. Genetic, factor age, and gender were reported to be involved in the clearance of HBsAg. However, the rate of HBsAg seroclearance in CHB patients is still low globally and few of the single-nucleotide polymorphism (SNP) had been identified to associated with HBsAg seroclearance in CHB patients.Recently, 3 associated SNPs (rs7944135, rs171941, and rs6462008) were reported in the clearance of HBsAg in the Korean population. However, these SNPs have not been investigated in the CHB Taiwanese population. In present study, these 3 SNPs were genotyped in 2565 Taiwanese CHB patients including 493 CHB patients with HBsAg seroclearance and 2072 without HBsAg seroclearance.We observed that SNP rs7944135 was solely associated with HBsAg seroclearance. Subjects with the AA genotype at rs7944135 of macrophage-expressed gene 1 had a higher susceptibility to HBsAg clearance, compared to those with the AG or GG genotype under the genotypic model (odds ratio [OR] = 1.76. 95% confidence interval [CI] = 1.14-2.72, P = .045). Furthermore, we found a 1.74-fold increased risk of acquiring HBsAg seroclearance associated with the AA genotype compared to AG + GG of rs7944135 under the recessive model (OR = 1.74. 95% CI = 1.13-2.66, P = .014). According to the cumulative fraction curve with the log-rank test revealed that patients with the AA genotype of rs7944135 showed higher susceptibility to occur HBsAg seroclearance (P = .039) and HBV DNA undetectable (P = .0074) compared to those with the AG or GG genotype.This study examined the associations of 3 SNPs (rs7944135, rs171941, and rs6462008) with HBsAg seroclearance, and we identified that rs7944135 is solely associated with HBsAg seroclearance in Taiwanese CHB patients.

Association of HLA-DPA1 and HLA-DPB1 polymorphisms with spontaneous HBsAg seroclearance in Caucasians

BACKGROUND & AIMS

Acute hepatitis B virus (HBV) infections may clear spontaneously or become chronic and run through different phases. The single nucleotide polymorphisms (SNPs) rs3077, rs9277535 and rs9277534 within the human leucocyte antigen (HLA)-DP gene have been found to be associated with HBV susceptibility and persistence in Asians. However, evidence for the influence of these variants in Caucasians has been limited so far. The aim of our study was to investigate the impact of these polymorphisms on the outcome of HBV infections in a large Caucasian population.

METHODS

In this case-control study, we retrospectively analysed 1111 Caucasian individuals, including 618 with chronic HBV infections (CHB), 239 with spontaneous HBsAg seroclearance (SC) and 254 healthy controls (HC). The rs3077, rs9277535 and rs9277534 SNPs were genotyped by a polymerase chain reaction from blood samples and melting curve analysis.

RESULTS

A significant difference in the allele distributions was observed only for the rs3077 SNP between the HC and the CHB group as well as between the SC and CHB groups. The rs3077-C allele was associated with a lower probability for spontaneous HBsAg seroclearance in comparison with the rs3077-T allele (OR 0.704, 95% CI 0.509-0.974; P = 0.033). No association of the three SNPs with the stages of chronic HBV infection was found.

CONCLUSION

This is the first study demonstrating an association of the rs3077-T allele with spontaneous HBsAg seroclearance in Caucasians. Further studies are needed to elucidate the role of HLA-DP variants in disease pathogenesis and their potential role for individualized disease management.

Hepatitis B surface antigen loss after discontinuing nucleos(t)ide analogue for treatment of chronic hepatitis B patients is persistent in White patients

OBJECTIVE

The objective of this study was to determine the long-term clinical outcome and persistence of hepatitis B surface antigen (HBsAg) loss after discontinuation of treatment.

BACKGROUND

The prognosis of patients with chronic hepatitis B (CHB) treated with nucleos(t)ide analogues (NAs) who discontinue treatment after loss of HBsAg remains largely unknown, particularly in White patients.

PATIENTS AND METHODS

We analysed a cohort of patients with CHB who discontinued NA treatment after loss of HBsAg. A total of 69 patients with hepatitis-B-e antigen-positive or hepatitis-B-e antigen-negative CHB with undetectable HBsAg during NA treatment were included after discontinuation of treatment, and followed up for a median period of 37.8 months (interquartile range: 23.8-54.6 months).

RESULTS

At the end of follow-up, none of the patients showed spontaneous reappearance of HBsAg and only one patient had detectable hepatitis B virus DNA (22 IU/ml). Another patient negative for HBsAg and anti-HBs developed hepatitis B virus reactivation without elevated transaminases after treatment with corticosteroids and vincristine for dendritic cell neoplasm, 38 months after withdrawal of the antiviral treatment. Regarding clinical outcome, a patient with cirrhosis developed hepatocellular carcinoma, 6.6 years after discontinuing treatment. None of the patients had hepatic decompensation or underwent liver transplantation.

CONCLUSION

HBsAg clearance after discontinuing NAs in patients with CHB is persistent and associated with good prognosis. The risk for developing hepatocellular carcinoma persists among patients with cirrhosis.

Interleukin 28A.rs12980602 and interleukin 28B.rs8103142 genotypes could be protective against HCV infection among Egyptians

Previous studies showed that interleukin (IL)-28B gene polymorphisms were associated with hepatitis C Virus (HCV) infection and treatment outcomes. We tested whether single-nucleotide polymorphisms (SNPs) in IL-28A and IL-28B are associated with HCV infection among Egyptians with HCV genotype 4 infections. We enrolled 144 chronic HCV patients, 72 spontaneously resolved HCV subjects, and 69 healthy controls. Four SNPs in IL-28A and IL-28B genes (IL-28A.rs12980602, IL-28B.rs12979860, IL-28B.rs8099917, and IL-28B.rs8103142) were genotyped. The most frequent IL-28B haplotype "TCT" was significantly more frequent in HCV-infected subjects than in HCV negative subjects (62.2% vs. 48.6%, respectively; p = 0.005). The frequency of IL-28A.rs12980602 "T" allele was significantly higher than the "C" allele in healthy controls compared to HCV-infected subjects (p < 0.001) with the "TT" genotype significantly higher in healthy controls compared to HCV-infected subjects (p < 0.001) with no association with viral load (p = 0.11) among chronically infected subjects. The results, also, confirmed the previous role of IL-28B SNPs in predicting HCV infection outcome. Importantly, IL-28B.rs8099917 "TT" genotype was significantly associated with low viral load in HCV-infected subjects, while the remaining three SNPs did not. The three IL-28B SNPs were in linkage disequilibrium (D' > 0.68; r2 > 0.43) for all comparisons in HCV patients, while there was no linkage disequilibrium of IL-28A polymorphisms and the three IL-28B SNPs. In conclusion, IL-28A.rs12980602 and IL-28B.rs8103142 TT genotype could be protective against HCV infection. Also, IL-28B.rs12979860, IL-28B.rs8099917, and IL-28B.rs8103142 SNPs predicted the outcome of HCV infection among genotype-4-infected Egyptians. Moreover, IL-28B.rs8099917 SNP affected the viral load in chronic HCV patients.

Genetic Factors That Affect Spontaneous Clearance of Hepatitis C or B Virus, Response to Treatment, and Disease Progression

Hepatitis C virus (HCV) and hepatitis B virus (HBV) infections can lead to cirrhosis, end-stage liver disease, and hepatocellular carcinoma. Over the past decade, studies of individuals infected with these viruses have established genetic associations with the probability of developing a chronic infection, risk of disease progression, and likelihood of treatment response. We review genetic and genomic methods that have been used to study risk of HBV and HCV infection and patient outcomes. For example, genome-wide association studies have linked a region containing the interferon lambda genes to spontaneous and treatment-induced clearance of HCV. We review the genetic variants associated with HCV and HBV infection, and how these variants affect specific expression or activities of their products. Further studies of these variants could provide insights into risk factors for and mechanisms of chronic infection and disease progression, as well as new strategies for treatment.

Incidence and determinants of spontaneous hepatitis B surface antigen seroclearance and seroconversion in hepatitis B e antigen-negative chronic infection patients: A population-based prospective cohort

Seroclearance of hepatitis B surface antigen (HBsAg) has been widely studied; however, seroconversion of HBsAg and characteristics of viral load among hepatitis B e antigen (HBeAg)-negative chronic infection patients after HBsAg lost is not clear. We performed a large-scale study in a HBeAg-negative chronic infection cohort to evaluate spontaneous HBsAg seroclearance incidence from October 2012 to April 2017 in Jiangsu province, China. We also elucidated the characteristics of HBsAg seroconversion and hepatitis B virus (HBV) DNA detectability among patients who cleared HBsAg. A total of 2997 HBeAg-negative chronic infection patients (mean age 52.3 ± 12.9 years at baseline) were included. With 10 519 person-years of follow-up, 348 patients successfully spontaneously cleared HBsAg, with an incidence rate of 3.31 per 100 person-years. Patients with HBV DNA detectable ~1999 IU/mL at baseline had a lower probability of HBsAg seroclearance relative to those with undetectable HBV DNA, with a hazard ratio of 0.31 (95% CI = 0.23, 0.41). HBsAg seroconversion occurred in 37.3% of those patients who cleared HBsAg. The geometric mean of anti-HBs among those with HBsAg conversion was 79.4 mIU/mL. Female had a higher HBsAg seroconversion rate (P = 0.011). Among those with HBsAg seroclearance, 11.2% still had HBV DNA levels of higher than 100 IU/mL. Patients with higher HBV DNA at baseline had a higher risk of detectable HBV DNA levels even after HBsAg seroclearance (P < 0.001). This study reveals HBsAg seroconversion rates and HBV DNA undetectability epidemiological characteristics of patients with HBsAg seroclearance and suggests that monitoring HBV DNA is needed when managing HBeAg-negative chronic patients, even after clearing HBsAg.

Multiple doses of hepatitis B recombinant vaccine for chronic hepatitis B patients with low surface antigen levels: a pilot study

BACKGROUND

Seroclearance of hepatitis B surface antigen (HBsAg) has been rarely achieved in the treatment of chronic hepatitis B (CHB) patients. We administered HBsAg-based recombinant vaccine in patients with low HBsAg concentrations.

METHODS

Twenty hepatitis B e antigen-negative patients, with HBsAg < 1000 IU/ml, were enrolled. Vaccines were administered every 8 weeks for 48 weeks (seven doses). HBsAg levels and anti-HBs were assayed longitudinally until 48 weeks post-vaccination. HLA genotyping and cDNA microarray were performed to search for response predictors.

RESULTS

Nineteen patients completed the study. At the end of vaccination, HBsAg declined significantly (Δ = - 0.27 ± 0.49 log IU/ml, p = 0.0005). The annual decline rate was significantly greater than that of an age-, gender-, and baseline HBsAg-matched control group (Δ = - 0.18 ± 0.46 versus + 0.11 ± 0.42 log IU/ml/year; p = 0.0229). Two patients achieved HBsAg seroclearance. Fourteen had significant HBsAg decline (Δ = - 0.64 ± 0.88 log IU/ml). No significant adverse events occurred during the trial. cDNA microarray identified the top up- and down-regulated genes in responders as HLA-DQ and HLA-DMB, respectively. HLA genotyping identified HLA-DQB1*04, HLA-DRB1*04, and HLA-B*40 as predictors for non-response (p = 0.0499, 0.0152, and 0.0314, respectively).

CONCLUSIONS

In low-level HBsAg CHB patients, serial HBsAg-based vaccinations were safe, resulting in significant HBsAg decline. HLA gene expression and genotypes played a role in vaccine responsiveness (ClinicalTrials.gov Identifier: NCT01817725).

Current concepts on immunopathogenesis of hepatitis B virus infection

Hepatitis B virus (HBV) infection is a leading cause of liver damage and hepatic inflammation. Upon infection, effective antiviral responses by CD8+ T cells, CD4+ T cells, Natural killer (NK) cells, and monocytes can lead to partial or complete eradication of the viral infection. To date, many studies have shown that the production of inhibitory cytokines such as Interleukin 10 (IL-10), Transforming growth factor beta (TGF-β), along with dysfunction of the dendritic cells (DCs), and the absence of efficient innate immune responses could lead to T cell exhaustion, development of persistent infection, and inability to eradicate the viral infection from liver. Understanding the immunopathogenesis of the virus could be useful in providing further insights toward novel strategies in the eradication of HBV infection.

Correlation of HLA-DP/DQ polymorphisms with transplant etiologies and prognosis in liver transplant recipients

Previous study has identified that the genetic variants in the human leukocyte antigen (HLA)-DP/DQ region were strongly associated with hepatitis B virus (HBV) infection. But their roles in liver function recovery after hepatic transplantation were still obscure. This study aimed to investigate whether HLA-DP/DQ polymorphisms were associated with post-transplant etiologies and prognosis in Chinese liver transplant recipients.A total of 144 liver transplant recipients were enrolled, which were divided into 2 groups according to the transplant etiology: HBV-related disease and non-HBV-related disease. HBV-related disease includes 3 subgroups: liver cirrhosis, hepatocellular carcinoma, and progressive HBV hepatitis. Three single-nucleotide polymorphisms HLA-DP (rs3077 and rs9277535) and HLA-DQ (rs7453920) were studied in all recipients by high-resolution melting curve analysis. Liver function indices (albumin, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, gamma-glutamyltranspeptidase, direct bilirubin, total bilirubin) and coagulation indices (prothrombin time, platelet, international normalized ratio, fibrinogen) were routinely tested. After transplant, 10 recipients who were positive for HBsAg or with elevation in HBV virus load were regarded as HBV recurrence.No significant association of HLA-DP/DQ polymorphisms with HBV recurrence or transplant etiology was observed (P < .05). Recipients with HLA-DQ (rs7453920) AG and AA genotype had lower direct bilirubin levels than GG genotype individuals, especially on the 14th day after surgery (17.80 vs. 5.35, P  =  .038). Patients with A alleles displayed earlier liver function recovery than patients with G alleles (7 vs. 6 months). No significant correlation was shown in HLA-DP rs3077 and rs9277535 with HBV infection or liver function recovery (P < .05).Our study concluded that HLA-DP (rs3077 and rs9277535) and HLA-DQ (rs7453920) were not significantly associated with HBV recurrence or HBV susceptibility, but HLA-DQ rs7453920 was related to prognosis of liver transplant recipients. HLA-DQ rs7453920 A might be used as an indicator of earlier recovery and better prognosis after transplantation.

Association between chronic hepatitis B virus infection and HLA-DP gene polymorphisms in the Turkish population

AIM

Hepatitis B virus (HBV) affects approximately 360 million people worldwide. 10-15% of patients with chronic HBV develop liver cirrhosis (LC), liver failure and hepatocellular carcinoma (HCC). Chronic HBV infection or HBV clearance is influenced by both viral and host factors. In genome-wide association studies (GWAS), the human leukocyte antigen (HLA) gene polymorphisms rs3077 and rs9277535 were identified to be associated with chronic hepatitis B. HLA genes have been linked to immune response to infectious agents. Genetic variants in HLA genes influence HLA mRNA expression which might also affect antigen presentation. We evaluated the association between HLA gene polymorphisms and the risk for persistent HBV infection.

METHODS

In the current study, HLA gene polymorphisms were investigated in a case-control study of 294 chronic HBV patients and 234 persons with HBV natural clearance by using a real-time polymerase chain reaction (RT-PCR).

RESULTS

The results showed that rs9277535 allele frequency is associated with HBV infection in the Turkish subjects examined (P=0.048). However, no association was found for rs3077. Additionally, the AG haplotype block showed a protective effect against the risk of persistent HBV infection (for the rs3077A/rs9277535G, OR=0.52; 95% 0.34-0.80, P=0.003).

CONCLUSIONS

Our results, for the first time, demonstrate that HLA-DPB1 gene rs9277535A allele has a major effect on the risk of persistent HBV infection. We suggest that further independent studies are necessary to clarify the association of these polymorphisms with persistence or natural clearance of HBV infection in Caucasian populations.

Chronic hepatitis B surface antigen seroclearance-related immune factors

The ultimate aims of the treatment of hepatitis B virus infection are the loss of hepatitis B surface antigen (HBsAg) and hepatitis B surface antibody seroconversion. Unfortunately, these goals are rarely reached. Many factors are associated with HBsAg seroconversion, including genetic, immune, and viral factors. However, the mechanism of HBsAg seroclearance, and particularly the immune mechanism, is still difficult to elucidate. The immune factor interferon-α is currently the main antiviral therapy for chronic hepatitis B virus infection. However, a sustained shift from response of HBsAg to hepatitis B surface antibody seroconversion is rarely obtained. Recent studies have revealed that several of the newly identified immune factors are closely related to the removal of HBsAg. In this article, we review recent studies on these immune factors, their influence on hepatitis B progression, and HBsAg seroconversion.

New perspectives of biomarkers for the management of chronic hepatitis B

With recent advances in molecular and genomic investigations, the impact of hepatitis B viral and host factors on the progression of chronic HBV infection has been explored. For viral factors, hepatitis B viral load is a strong predictor for liver disease progression. Hepatitis B viral kinetics appear to be important for successful anti-viral therapy. Serum HBsAg level serves as a complementary marker to viral load for the prediction of HBV-related adverse outcomes in patients with low viral load. In those with low viral load, high serum HBsAg level is associated with higher risks of cirrhosis and HCC. Hepatitis B core-related antigen (HBcrAg) induces host immune responses, and the reduction of the HBcrAg level as well as the increment of total anti-HBc level are significantly associated with favorable outcomes. HBV genotypes (genotype C/D) and mutants (basal core promoter and deletion mutation in pre-S genes) are well known viral genetic markers to predict disease progression. For host factors, serum inflammatory biomarkers have been developed to evaluate the HBV-associated hepatic necroinflammation and fibrosis. Host single nucleotide polymorphism on sodium taurocholate cotransporting polypeptide (NTCP, an HBV entry receptor) may be associated with a decreased risk for cirrhosis and HCC. In conclusion, patients with chronic hepatitis B should be evaluated with relevant viral and host markers to identify those who are at a higher risk of liver disease progression and then receive timely antiviral therapy.

HBsAg may reappear following reactivation in individuals with spontaneous HBsAg seroclearance 8 years previously

HBsAg reappearance may constitute not only a risk for liver disease but also an infectious source. We aimed to determine whether HBsAg may reappear after spontaneous HBsAg seroclearance. A cohort of 2999 HBsAg-positive subjects aged 30-55 years was recruited in Guangxi, China in 2004. HBsAg was tested every 6 months from July 2004 to June 2007, then, one more time in December 2013. The results showed that spontaneous HBsAg seroclearance occurred in 41 subjects in the first 3 years, giving a 0·54% annual seroclearance rate. Thirteen of the 41 subjects were randomly tested for HBsAg in 2013. Four subjects became HBsAg positive. S gene sequences of HBV were analysed from serum collected before seroclearance and after reappearance, respectively, for subject QS840 (11 and 12 clones), subject TN98 (13 and 13 clones) and subject WX227 (10 and 8 clones). Serotype, subgenotype and amino-acid substitution pattern in each sample collected after reappearance was observed in the sample collected before HBsAg seroclearance. Nucleotide similarity between the two sequences from each subject was >99% and five sequences from subject TN98 were the same. In conclusion, following reactivation, HBsAg may reappear in individuals with spontaneous HBsAg seroclearance many years previously.

Clinical Relevance of HLA Gene Variants in HBV Infection

Host gene variants may influence the natural history of hepatitis B virus (HBV) infection. The human leukocyte antigen (HLA) system, the major histocompatibility complex (MHC) in humans, is one of the most important host factors that are correlated with the clinical course of HBV infection. Genome-wide association studies (GWASs) have shown that single nucleotide polymorphisms (SNPs) near certain HLA gene loci are strongly associated with not only persistent HBV infection but also spontaneous HBV clearance and seroconversion, disease progression, and the development of liver cirrhosis and HBV-related hepatocellular carcinoma (HCC) in chronic hepatitis B (CHB). These variations also influence the efficacy of interferon (IFN) and nucleot(s)ide analogue (NA) treatment and response to HBV vaccines. Meanwhile, discrepant conclusions were reached with different patient cohorts. It is therefore essential to identify the associations of specific HLA allele variants with disease progression and viral clearance in chronic HBV infection among different ethnic populations. A better understanding of HLA polymorphism relevance in HBV infection outcome would enable us to elucidate the roles of HLA SNPs in the pathogenesis and clearance of HBV in different areas and ethnic groups, to improve strategies for the prevention and treatment of chronic HBV infection.

Host nucleotide polymorphism in hepatitis B virus-associated hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is etiologically linked with hepatitis B virus (HBV) and is the leading cause of death amongst 80% of HBV patients. Among HBV affected patients, genetic factors are also involved in modifying the risk factors of HCC. However, the genetic factors that regulate progression to HCC still remain to be determined. In this review, we discuss several single nucleotide polymorphisms (SNPs) which were reportedly associated with increased or reduced risk of HCC occurrence in patients with chronic HBV infection such as cyclooxygenase (COX)-2 expression specifically at COX-2 -1195G/A in Chinese, Turkish and Egyptian populations, tumor necrosis factor α and the three most commonly studied SNPs: PAT-/+, Lys939Gln (A33512C, rs2228001) and Ala499Val (C21151T, rs2228000). In genome-wide association studies, strong associations have also been found at loci 1p36.22, 11q22.3, 6p21 (rs1419881, rs3997872, rs7453920 and rs7768538), 8p12 (rs2275959 and rs37821974) and 22q11.21. The genes implicated in these studies include HLA-DQB2, HLA-DQA1, TCF19, HLA-C, UBE2L3, LTL, FDX1, MICA, UBE4B and PG. The SNPs found to be associated with the above-mentioned genes still require validation in association studies in order to be considered good prognostic candidates for HCC. Screening of these polymorphisms is very beneficial in clinical experiments to stratify the higher or lower risk for HCC and may help in designing effective and efficient HCC surveillance programs for chronic HBV-infected patients if further genetic vulnerabilities are detected.

Quantitative assessment of common genetic variations in HLA-DP with hepatitis B virus infection, clearance and hepatocellular carcinoma development

Hepatitis B virus (HBV) infection is the predominant risk factor for chronic hepatitis B (CHB), liver cirrhosis (LC) and hepatocellular carcinoma (HCC). Recently, genome-wide association studies have identified human leukocyte antigen (HLA)-DP polymorphisms (rs3077 and rs9277535) as a new chronic HBV infection susceptibility locus. Since then, the relationship between HLA-DP polymorphisms and various outcomes of HBV infection has been reported. However, the results have been inconclusive. To derive a more precise estimation of the relationship between HLA-DP polymorphisms and various outcomes of HBV infection, a meta-analysis of 62,050 subjects from 29 case-control studies was performed. We found that rs3077 and rs9277535 in HLA-DP significantly decreased HBV infection risks and increased HBV clearance possibility in a dose-dependent manner. In the subgroup analysis by ethnicity, study design and sample size, significant associations were found for these polymorphisms in almost all comparisons. Meanwhile, haplotype analyses of the two polymorphisms revealed a significant association between the combination of these alleles and HBV infection outcomes. However, no significant results were observed in HCC development. Our results further confirm that genetic variants in the HLA-DP locus are strongly associated with reduced HBV infection and increased the likelihood of spontaneous viral clearance.

Higher lifetime chance of spontaneous surface antigen loss in hepatitis B carriers with genotype C infection

BACKGROUND

Clearance of hepatitis B surface antigen (HBsAg) indicates clinical control of hepatitis B virus (HBV) infection. However, little is known about the impact of viral genomic variations on HBsAg loss.

METHODS

We explored the association between viral genomic factors and HBsAg loss in 2121HBeAg-negative patients. HBV pre-core stop codon (1896) and basal core promoter (BCP) (1762/1764) sequences were determined in patients with HBV DNA ≥200 IU/mL (N = 1693). The effect of HBV genotype on HBsAg loss was further validated in the whole cohort of 3445 HBsAg carriers.

RESULTS

The cumulative lifetime (age 28-75 years) incidence of HBsAg loss was 50.4% in 2121 HBeAg-negative patients. We found that genotype C, but not pre-core stop codon or BCP mutants, was associated with HBsAg loss. Compared to genotype B patients, genotype C patients had higher lifetime chance of HBsAg loss, with hazard ratio of 1.8 (95% confidence interval: 1.4-2.4). Multivariable analysis showed that male sex, elevated ALT levels, lower serum HBV DNA and HBsAg levels, and genotype C infection were associated with higher chance of HBsAg loss independently. We then performed sensitivity analysis, which re-included HBeAg-positive, cirrhotic and treatment-experienced patients, and confirmed the robustness of our results in 3445 HBsAg carriers.

CONCLUSION

Genotype C infection, compared to genotype B, is associated with a higher lifetime chance of HBsAg loss in Asian HBV carriers.

The spectrum of HBV/HCV coinfection: epidemiology, clinical characteristics, viralinteractions and management

Monoinfection with either hepatitis B (HBV) or C virus (HCV) represents one of the major causes of chronic liver disease globally. However, in endemic areas a substantial number of patients are infected with both viruses mainly as a result of the common routes of transmission. Numerous studies have demonstrated that dually infected patients carry a greater risk of advanced liver disease, cirrhosis and hepatocellular carcinoma compared with monoinfected patients. The choice of treatment is based on the virological profile of each patient taking into account the dominant virus pattern. In predominant HCV, standard combination treatment with pegylated interferon and ribavirin has proven equally effective in HBV/HCV-coinfected patients as well as in HCV-monoinfected patients. Strikingly, approximately 60% of patients with inactive HBV infection before HCV treatment may present HBV reactivation while others experience hepatitis B surface antigen seroconversion after clearing HCV, demonstrating the complexity of the interaction between the two viruses during the follow up. The therapeutic strategies for the predominant HBV dually infected patients are more vague, although high genetic barrier nucleos(t)ide analogues play an indisputable role. Finally, the recently approved combination treatments for chronic hepatitis C containing direct-acting antivirals may definitely change the treatment protocols in the future although there is no experience with these drugs in dually infected patients until today.

Loss of hepatitis B surface antigen in a real-life clinical cohort of patients with chronic hepatitis B virus infection

BACKGROUND & AIMS

Hepatitis B surface antigen (HBsAg) clearance is the main indicator of viral cure in patients infected with the hepatitis B virus (HBV). We sought to identify the parameters associated with HBsAg loss in a well-characterized real-life clinical cohort of chronically HBV-infected patients.

METHODS

Patients with chronic HBV infection were prospectively included, classified according to the disease stage, and followed up to determine parameters associated with HBsAg clearance.

RESULTS

In total, 315 patients were followed up for a mean of almost 6 years. At study entry, 109 (34.6%) were inactive HBsAg carriers, 204 (64.8%) had chronic active hepatitis (CAH), and two (0.6%) were immune-tolerant carriers. During follow-up, 128 (62.7%) of the 204 patients with CAH received antiviral therapy. Sixty-nine had HBeAg-positive CAH: 55 (79.7%) were treated and 14 (20.3%) untreated. One hundred thirty-five had HBeAg-negative CAH: 73 (54.1%) were treated and 62 (45.9%) untreated. Inactive carriers showed an annual HBsAg clearance incidence rate of 23.4 cases per 1000 persons-years, which was higher than that of CAH groups. The clearance incidence rates (in cases per 1000 persons-years) of CAH groups were: treated HBeAg-positive (20.7), untreated HBeAg-positive (19.1), treated HBeAg-negative (10.1), and untreated HBeAg-negative (8.1). Older age (P = 0.001) and inactive carrier status (P = 0.019) were independent predictors of HBsAg clearance.

CONCLUSION

In a well-characterized real-life clinical cohort of chronically HBV-infected patients in various disease phases, older age, and inactive HBsAg carrier status were the only predictors of HBsAg clearance, whereas anti-HBV therapy only marginally increased annual incidence of HBsAg loss.

The effects of cytokines on spontaneous hepatitis B surface antigen seroconversion in chronic hepatitis B virus infection

We examined the role of human cytokines in the natural course of hepatitis B surface Ag (HBsAg) seroconversion in chronic hepatitis B virus (HBV) infection. The clinical course of spontaneous HBsAg seroconversion was assessed in 296 chronically HBV-infected patients. Single nucleotide polymorphisms (SNPs) in IL-1β, IL-2, IL-4, IL-10, IL-12β, IL-13, IL-27, and IFN-γ genes were examined in 296 chronically HBV-infected patients and another 193 HBV recoverers. The HBsAg a determinant sequence of chronically HBV-infected subjects with and without HBsAg seroconversion was also analyzed. The start of the immune-clearance phase (serum alanine aminotransferase levels > 30 IU/l) before the age of 48 mo and hepatitis B e Ag (HBeAg) seroconversion before the age of 10 y predicted spontaneous HBsAg seroconversion in chronically HBV-infected patients (odds ratios 17.7 and 5.0; p < 0.001 and p < 0.002, respectively). The A-allele of IL-10 SNP rs1800872 was associated with higher IL-10 serum levels, and the G-allele of IL-12β SNP rs3212217 was associated with sustained high serum IL-12p70 levels during the immune-clearance phase. Both were predictors of spontaneous HBsAg seroconversion and HBV recovery (odds ratios 4.0 and 26.3; p = 0.002 and p < 0.001, respectively). Spontaneous HBsAg seroconversion was not related to sex, HBV genotype, or HBsAg a determinant mutation. The start of immune-clearance phase, age at HBeAg seroconversion, and serum IL-10 and IL-12 levels are associated with the course of the immune-clearance phase in chronic HBV infection, and are predictive of spontaneous HBsAg seroconversion and HBV recovery.

Clinical significance of circulating miR-122 in patients with dual chronic hepatitis B and C virus infection

BACKGROUND

The clinical significance of serum microRNA-122 (miR-122) has been shown in viral hepatitis B and C, respectively. Specifically, miR-122 stimulates hepatitis C virus (HCV) replication but suppresses hepatitis B virus (HBV) replication. The profile and clinical significance of serum miR-122 in patients with dual chronic hepatitis B and C would be an interesting and important clinical issue.

METHODS

A total of 76 patients with HBV/HCV dual infection, 105 with HCV monoinfection and 39 with HBV monoinfection were enrolled. All patients received peginterferon alfa-2a (PEG-IFN)-based treatment. Serum miR-122 levels were quantified by using a sensitive hybridization-based assay.

RESULTS

At baseline, the serum miR-122 level was lower in HCV-monoinfected patients than in HBV-monoinfected patients, whereas HBV coinfection increased the expression of miR-122. In multivariate analysis, the serum miR-122 level was positively correlated with the serum HBsAg level in patients with HBV/HCV dual infection and those with HBV monoinfection. In dually infected patients who received PEG-IFN-based treatment, a high baseline miR-122 level was positively correlated with a greater reduction of the posttreatment serum HBsAg level.

CONCLUSION

In summary, the serum miR-122 level is highly correlated with the HBsAg level in HBV/HCV dually infected patients and may serve as a biomarker to predict posttreatment HBsAg decline.

Association between single-nucleotide polymorphisms and early spontaneous hepatitis B virus e antigen seroconversion in children

Background

The disease progression following hepatitis B virus (HBV) infection is associated with single-nucleotide polymorphisms (SNPs). However, the role of SNPs in chronic HBV infection in children remains unclear. Here, we investigate the association between SNPs and early spontaneous hepatitis B e antigen (HBeAg) seroconversion in children with chronic hepatitis B infection.

Methods

This was a retrospective cohort study. We genotyped seven SNPs in the following genes, interleukin (IL)-10 (rs1800871 and rs1800872), human leukocyte antigen (HLA)-DPA1 (rs3077), HLA-DPB1 (rs9277535), HLA-DQB2 (rs7453920), HLA-DQB1 (rs2856718), and IL28B (rs8099917), in patients with chronic HBV infection using PCR and sequencing. These variants were analyzed for an association with early HBeAg seroconversion in children.

Results

Of 225 Japanese patients with chronic hepatitis B virus infection (male/female: 105/120, median age at initial visit: 6 years; range 0–44 years), 52 achieved spontaneous HBeAg seroconversion at the age of 10 years or younger (G1: early seroconversion group), and 57 did not achieve spontaneous HBeAg seroconversion under the age of 20 years (G2: late or no seroconversion group). Of the seven SNPs, only the HLA-DPA1 SNP displayed a low p-value (P = 0.070), but not significant, to have early HBeAg seroconversion in the dominant model and in the allele model (P =  0.073) using the chi-square test. The association study found a low p-value, but not significant, to have early HBeAg seroconversion in the dominant model for HLA-DPA1 (genotype TC + TT vs. CC, P = 0.070, odds ratio: 2.016, 95% confidence interval: 0.940-4.323) using a logistic regression model.

Conclusion

Although the HLA-DPA1 SNP did not show a statistically significant association with early HBeAg seroconversion in this study, the HLA-DPA1 SNP might increase the likelihood of achieving early spontaneous HBeAg seroconversion in children.

Association of HLA-DP/DQ and STAT4 polymorphisms with HBV infection outcomes and a mini meta-analysis

BACKGROUND

Though HLA-DP/DQ is regarded to associate with HBV susceptibility and HBV natural clearance, its role in hepatocellular carcinoma (HCC) development is obscure. And the role of STAT4 in HBV susceptibility and clearance as well as HCC development is still contentious. Therefore, we conducted this study, aiming to clarify these obscure relationships.

METHODS

We recruited 1312 Chinese Han subjects including healthy controls, HBV carriers and HCC patients in the experiment stage. The meta-analysis included 3467 HCC patients and 5821 HBV carriers to appraise the association with HCC development.

RESULTS

Consistent with previous studies, HLA-DP/DQ associated with HBV susceptibility and HBV natural clearance (p<0.05). However, the experiment showed that HLA-DP rs3077, rs9277535 and rs7453920 did not associate with HCC development (dominant model, rs3077, OR = 0.86, 95%CI = 0.62-1.18; rs9277535, OR = 0.94, 95%CI = 0.68-1.30; rs7453920, OR = 0.75, 95%CI = 0.44-1.27). Meta-analysis again consolidated this conclusion (allele model, rs3077, OR = 0.94, 95%CI = 0.87-1.02; rs9277535, OR = 1.04, 95%CI = 0.97-1.11; rs7453920, OR = 0.89, 95%CI = 0.76-1.02). As for STAT4 rs7574865, we did not find any significant association with HBV susceptibility (OR = 0.91, 95%CI = 0.66-1.26) or HBV natural clearance (OR = 1.13, 95%CI = 0.86-1.49). Moreover, current data failed to acquire positive connection of rs7574865 with HCC development (experiment, OR = 0.86, 95%CI = 0.62-1.19; meta-analysis, OR = 0.87, 95%CI = 0.74-1.03), which may be due to the small sample size.

CONCLUSIONS

HLA-DP/DQ polymorphisms (rs3077, rs9277535, rs7453920) did not associate with HCC development, but did correlate with HBV susceptibility and HBV natural clearance. STAT4 rs7574865 seemed not to correlate with HBV susceptibility or natural clearance. And it seemed rather ambiguous in its role on HCC development at present.

HLA-DPB1 Variant Effect on Hepatitis B Virus Clearance and Liver Cirrhosis Development Among Southwest Chinese Population

BACKGROUND

Previous studies have shown that genetic variants in HLA-DP genes affect disease progression in hepatitis B virus (HBV) infection.

OBJECTIVES

We aimed to evaluate possible association between HLA-DPB1 rs9277534 polymorphism and different clinical complications of hepatitis B virus (HBV) infection.

MATERIALS AND METHODS

Snapshot assay was used to investigate the association of rs9277534 polymorphism in 342 patients with persistent HBV infection and 342 age and gender-matched HBV spontaneous clearance controls. Patients were categorized into asymptomatic HBV carriers (AsC, n = 104), chronic hepatitis B (CHB, n = 116), and liver cirrhosis (LC, n = 122) subgroups.

RESULTS

There was a significantly higher proportion of the rs9277534 minor allele A in HBV spontaneous clearance control than that in HBV persistent infection group (OR = 0.58, 95%CI = 0.46-0.73, P < 0.0001). Genotypic analysis showed that GA and AA genotypes were associated with HBV spontaneous clearance (GA: OR = 0.56, 95%CI = 0.40-0.79, P = 0.019; AA: OR = 0.24, 95%CI = 0.14-0.44, P < 0.0001). A significant difference was found between AsC and LC groups in the distribution of AA genotype (OR = 9.32, 95%CI = 1.293-67.14, P = 0.027).

CONCLUSIONS

Variant at rs9277534 could affect both the spontaneous clearance of HBV infection and progression from asymptomatic HBV carriers to HBV-related liver cirrhosis in Southwest Han Chinese population.

Peginterferon α in the treatment of chronic hepatitis B

INTRODUCTION

Hepatitis B virus (HBV) infection is a global health problem. Peginterferon α (PEG-IFN), which includes PEG-IFN α-2a (Pegasys) and PEG-IFN α-2b (Peg-Intron), can be used to treat patients with chronic hepatitis B (CHB) infection. A finite duration of PEG-IFN therapy may lead to long-term viral suppression. Clinically, it is important to identify super-responders and null-responders to PEG-IFN due to its substantial side effects.

AREAS COVERED

From the literature review, it is known that PEG-IFN is more effective for hepatitis B e antigen (HBeAg)-positive patients who have high pre-treatment alanine aminotransferase level, lower HBV DNA level and genotype A (vs genotype D), as well as those with more favourable viral predictors, such as precore stop codon or basal core promoter mutants infections in Asian patients and wild-type virus in Caucasian patients. For HBeAg-positive patients and HBeAg-negative patients with genotype D infection, PEG-IFN therapy could be terminated early at week 12 or 24 in primary non-responders defined by the Hepatitis B surface antigen stopping rules. With regard to host factors, single nucleotide polymorphisms of IL28B do not seem to affect the treatment outcomes in Asian patients, but its role in Caucasian patients remains disputed.

EXPERT OPINION

Most of the known predictors need validation by large prospective trials. In addition, we need to identify more baseline predictors for super-responders in order to achieve personalised PEG-IFN treatment for CHB.

Human genes involved in hepatitis B virus infection

Persistent hepatitis B virus (HBV) infection is a significant public health problem because it is a major cause of chronic liver disease, cirrhosis, and hepatocellular carcinoma (HCC). Roughly one-third of the world population has been infected with HBV and there are about 350 million (5%-6%) persistent carriers. HBV causes 80% of all liver cancer cases and is the second most important carcinogen, after smoking tobacco. There is an approximate 90% risk of becoming a persistent carrier following perinatal infection in infants born to e antigen positive carrier mothers and a 30% risk in pre-school children. Only 5%-10% of adults become persistent carriers following infection. Of individuals persistently infected with HBV, 10%-30% will develop liver cirrhosis and HCC. These highly variable outcomes in both clearance rates and disease outcomes in persistently infected individuals cannot be fully explained by differences in immunological, viral or environmental factors. Thus, differences in host genetic factors may affect the natural history of hepatitis B.

Updates on the treatment and outcomes of dual chronic hepatitis C and B virus infection

Dual hepatitis C virus (HCV)/hepatitis B virus (HBV) infection is found in HBV or HCV endemic areas, and in specific populations exhibiting a high risk of parenteral viral transmission. Clinical observations have revealed that HCV/HBV dually infected patients demonstrate a higher risk of liver disease progression compared with HBV or HCV monoinfected patients. The viral activity responsible for liver disease progression can be determined by examining the viral loads of HCV and HBV and by conducting liver biopsy examinations. Recent trials have confirmed that the combination therapy of peginterferon alpha-2a or 2b and ribavirin for dual hepatitis patients with HCV dominance appears to be as effective and safe as it is in patients with HCV monoinfections. Strikingly, approximately 60% of dually infected patients with inactive hepatitis B before treatment develop HBV reactivation after the clearance of the HCV. The clinical significance of this HBV reactivation and the strategy to prevent and treat this event should be determined. Furthermore, approximately 30% of dually infected patients lost hepatitis B surface antigen (HBsAg) within 5 years after the start of peginterferon-based therapy, and 40% of them harbored occult HBV infection. The underlying mechanisms of their accelerating HBsAg seroclearance and the development of occult HBV await further investigations. Moreover, the optimal treatment strategies for dually infected patients who are seropositive for the hepatitis B e antigen must be explored. Finally, the advent of new direct-acting antiviral-based anti-HCV therapy may change the optimal therapies for patients with dual hepatitis in the near future, which warrants further clinical trials.

Systematic review with meta-analysis: do interferon lambda 3 polymorphisms predict the outcome of interferon-therapy in hepatitis B infection?

BACKGROUND

Interferon lambda 3 (IFN-λ3) polymorphisms are the strongest genetic predictor of outcome of hepatitis C virus infection and of response to Pegylated interferon (PegIFN)-based therapy. Whether this holds true for hepatitis B virus (HBV) infection is matter of controversy.

AIM

To review the association between host genomics and spontaneous or interferon-induced clearance of HBV with specific reference to the recently identified interleukin 28B gene now renamed IFN-λ3.

METHODS

A literature search was performed on MEDLINE, EMBASE and Web of Science for English articles and abstracts using free text words and combinations of the following terms 'IL28B', 'IFN lambda', 'genomics', 'hepatitis B virus', 'interferon' 'GWAS', 'treatment', 'SNPs', 'HLA', 'polymorphisms'.

RESULTS

Genome-wide association studies convincingly demonstrated an association between SNPs in the HLA locus and spontaneous resolution of HBV infection in subgroups of Asian patients, yet no information is available for Caucasians. The preliminary observations of an association between IFN-λ3 SNP and virological and serological responses to IFN in both HBeAg-positive and -negative patients could not be replicated by subsequent studies. Yet, majority of studies performed so far suffer several limitations in terms of sample size, selection of the patients, endpoints of therapy, treatment strategies and duration of follow-up.

CONCLUSIONS

While host genetics is associated with an increased likelihood of spontaneous clearance of HBV among genotype B/C patients, the relationship between IFN-λ3 polymorphisms and response to IFN has not been confirmed. Further studies in large cohorts of homogeneous patients are required, before this genetic test can be recommended in clinical practice.

Genetic polymorphisms of the IFNλ genes are associated with biochemical features in Han Chinese with HCV infection from Yunnan Province, China

Hepatitis C virus (HCV) is the pathogenic factor for hepatitis C disease, which could lead to chronic or serious hepatic diseases. Previous studies have identified that the IL28B gene polymorphisms were associated with therapeutic effect and viral clearness of HCV patients. We aimed to test whether genetic polymorphisms of three IFNλ genes (IL28A, IL28B and IL29) are associated with HCV infection in Han Chinese. We collected whole blood of 261 HCV infectious patients without any therapy and 265 matched normal controls from Yunnan Province. Among these subjects, 28.4% (74/261) of HCV patients and 26.8% (71/265) of controls were male. Ten SNPs (rs8099917, rs10853728, rs11883177, rs12980602, rs4803224, rs11671087, rs11665818, rs8108008, rs7248931, and rs30461), which covered the whole region of the IL28A, IL28B, and IL29 genes, were genotyped. Our results showed that there was no association between genotypes and alleles of the IFNλ gene polymorphisms and HCV infection. One haplotype (TGCTGTGGAT), which was consisted of ten SNPs, showed a significantly higher frequency in HCV patients (11/522 = 2.1%) than in controls (1/530 = 0.2%) (P = 0.003). We performed association analyses for biochemical features and genotype of each SNP, and found that HCV patients with certain genotypes of some SNPs had a higher level of the ALT/AST ratio and total blood bilirubin (TBIL) compared to healthy controls. Our results suggested the IFNλ gene polymorphisms might be associated with clinical features of HCV patients from Yunnan Province, China.

Treatment of patients with dual hepatitis C virus and hepatitis B virus infection: resolved and unresolved issues

Dual hepatitis C virus (HCV)/hepatitis B virus (HBV) infection is not uncommon in HCV or HBV endemic areas and among subjects at risk of parenteral transmission. In patients dually infected with hepatitis C and B, the disease manifestations are usually more severe than those with either virus infection. In the past decade, the following issues have been resolved. In dually infected patients with active hepatitis C, combined pegylated interferon alfa plus ribavirin was effective, the treatment outcomes being similar to patients with HCV monoinfection. During long-term follow-up, the HCV response was sustained in around 97% of patients; and the long-term outcomes including the development of hepatocellular carcinoma and liver-related mortality were improved. However, several clinical issues remain to be resolved. First, host and viral factors influencing the long-term outcomes and treatment options in patients with dual HCV/HBV infection await further studies. Second, about 60% of dually infected patients with baseline undetectable serum HBV DNA levels develop HBV reactivation after the start of treatment. How to prevent and treat HBV reactivation should be clarified. Third, about 30% of dually infected patients lose hepatitis B surface antigen at 5 years after the end of combination therapy; the mechanisms need further investigations. Fourth, the optimal treatment strategies for dually infected patients with active hepatitis B or established cirrhosis should be explored in future clinical trials. Finally, the role of new direct-acting antiviral-based therapy for the treatment of patients with dual HCV/HBV infection also remains to be evaluated.

Human cytidine deaminases facilitate hepatitis B virus evolution and link inflammation and hepatocellular carcinoma

During hepatitis B virus (HBV)-induced hepatocarcinogenesis, chronic inflammation facilitates the evolution of hepatocellular carcinoma (HCC)-promoting HBV mutants. Cytidine deaminases, whose expression is stimulated by inflammatory cytokines and/or chemokines, play an important role in bridging inflammation and HCC. Through G-to-A hypermutation, cytidine deaminases inhibit HBV replication and facilitate the generation of HCC-promoting HBV mutants including C-terminal-truncated HBx. Cytidine deaminases also promote cancer-related somatic mutations including TP53 mutations. Their editing efficiency is counteracted by uracil-DNA glycosylase. Understanding the effects of cytidine deaminases in HBV-induced hepatocarcinogenesis and HCC progression will aid in developing efficient prophylactic and therapeutic strategies against HCC in HBV-infected population.

HLA-DP polymorphisms affect the outcomes of chronic hepatitis B virus infections, possibly through interacting with viral mutations

Genetic polymorphisms of HLA-DP have been associated with hepatitis B virus (HBV) persistence. We aimed to determine the effect of HLA-DP polymorphisms on the generation of HBV mutations and their interactions on the outcomes of HBV infection. rs3077, rs3135021, rs9277535, and rs2281388 were genotyped in 1,342 healthy controls, 327 HBV clearance subjects, and 2,736 HBV-positive subjects, including 1,108 hepatocellular carcinoma (HCC) patients, using quantitative PCR. HBV mutations were determined by sequencing. Multiplicative interactions of HLA-DP polymorphisms and viral mutations were assessed by multivariate logistic regression. rs3077 (from subjects with genotype CT combined with those from subjects with genotype TT [CT+TT] versus CC), rs3135021 (GA+AA versus GG), rs9277535 (GA+AA versus GG), and rs2281388 (CC versus CT+TT) significantly decreased HBV persistence. This effect was found only in genotype B HBV-infected subjects compared to HBV clearance subjects. HLA-DP polymorphisms promoting HBV clearance were associated with a lower prevalence of mutations increasing HCC risk (C1653T, T1674C/G, A1846T, G1896A and pre-S2 mutations and pre-S deletion in genotype C) and a higher prevalence of mutations decreasing HCC risk (G1652A, T1673C, T1674C, G1719T, G1730C, and G1799C in genotype B and A1727T in genotype C). Significant effects of viral mutations on cirrhosis and HCC were selectively evident in those with HLA-DP polymorphisms promoting HBV persistence. The interactions of C1653T, T1674C/G, and G1896A mutations with HLA-DP polymorphisms promoting HBV clearance significantly decreased cirrhosis risk. The interaction of rs9277535 AA with the T1674C/G or G1719T mutation in genotype C significantly decreased HCC risk. In conclusion, HLA-DP polymorphisms affect genotype B HBV clearance, regulate immune selection of viral mutations, and influence cirrhosis and HCC risks contributed by HBV mutations.

Unraveling the complexity of hepatitis B virus: from molecular understanding to therapeutic strategy in 50 years

Hepatitis B virus (HBV) is a well-known hepadnavirus with a double-stranded circular DNA genome. Although HBV was first described approximately 50 years ago, the precise mechanisms of HBV infection and effective therapeutic strategies remain unclear. Here, we focus on summarizing the complicated mechanisms of HBV replication and infection, as well as genomic factors and epigenetic regulation. Additionally, we discuss in vivo models of HBV, as well as diagnosis, prevention and therapeutic drugs for HBV. Together, the data in this 50-year review may provide new clues to elucidate molecular mechanisms of HBV pathogenesis and shed new light on the future HBV therapies.