RESUMEN
Hepatitis B virus (HBV) infection remains a significant global health burden. The genetic variation of HBV is complex. HBV can be divided into nine genotypes, which show significant differences in geographical distribution, clinical manifestations, transmission routes and treatment response. In recent years, substantial progress has been made through various research methods in understanding the development, pathogenesis, and antiviral treatment response of clinical disease associated with HBV genetic variants. This progress provides important theoretical support for a deeper understanding of the natural history of HBV infection, virus detection, drug treatment, vaccine development, mother-to-child transmission, and surveillance management. This review summarizes the mechanisms of HBV diversity, discusses methods used to detect viral diversity in current studies, and the impact of viral genome variation during infection on the development of clinical disease.
Asunto(s)
Evolución Molecular , Variación Genética , Genoma Viral , Virus de la Hepatitis B , Hepatitis B , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/clasificación , Humanos , Hepatitis B/virología , Genotipo , Antivirales/uso terapéutico , Antivirales/farmacologíaRESUMEN
Hepatitis B virus (HBV) infection leads to around 800,000 deaths yearly and is considered to be a major public health problem worldwide. However, HBV origins remain poorly understood. Here, we looked for bat HBV (BtHBV) in different bat species in Gabon to investigate the role of these animals as carriers of ancestral hepadnaviruses because these viruses are much more diverse in bats than in other host species. DNA was extracted from 859 bat livers belonging to 11 species collected in caves and villages in the southeast of Gabon and analyzed using PCRs targeting the surface gene. Positive samples were sequenced using the Sanger method. BtHBV DNA was detected in 64 (7.4%) individuals belonging to eight species mainly collected in caves. Thirty-six (36) sequences among the 37 obtained after sequencing were phylogenetically close to the RBHBV strain recently isolated in Gabonese bats, while the remaining sequence was close to a rodent HBV strain isolated in America. The generalized linear mixed model showed that the variable species best explained the occurrence of BtHBV infection in bats. The discovery of a BtHBV strain homologous to a rodent strain in bats raises the possibility that these animals may be carriers of ancestral hepadnaviruses.
Asunto(s)
Quirópteros , Variación Genética , Virus de la Hepatitis B , Hepatitis B , Filogenia , Quirópteros/virología , Animales , Gabón/epidemiología , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/aislamiento & purificación , Prevalencia , Hepatitis B/virología , Hepatitis B/epidemiología , Hepatitis B/veterinaria , ADN Viral/genética , Análisis de Secuencia de ADNRESUMEN
BACKGROUND: Hepatitis B virus (HBV) exhibits high prevalence rates within Ethiopia. The genetic diversity of HBV, marked by mixed genotype infections, may hold significant implications for the trajectory of disease and responses to treatment. Ethiopia grapples with a substantial public health challenge posed by co-infections involving HBV, hepatitis C virus (HCV), and human immunodeficiency virus 1 (HIV-1), particularly among vulnerable populations. METHODS: A comprehensive investigation into HBV, HCV, and HIV-1 co-infection was conducted. A total of 7,789 blood samples were meticulously analyzed, among which 815 exhibited HBV positivity. Among the HBV-positive samples, 630 were subjected to genotyping procedures, resulting in the identification of a prevalent trend of mixed infections characterized by HBV genotypes A/E/F (67.30%). Serological assessments were performed on 492 specimens to ascertain the presence of HCV and HIV-1 co-infections, revealing respective co-infection rates of 13.02% for HBV/HIV, 3.31% for HBV/HCV, and 2.07% for triple infection. RESULTS: The investigation revealed the intricate prevalence of co-infections in Ethiopia, notably underlining the continued transmission of viruses. The prominent occurrence of mixed HBV genotypes A/E/F suggests dynamic viral interactions and ongoing transmission pathways. These findings accentuate the necessity for targeted interventions and enhanced patient care, as co-infections carry significant clinical complexities. CONCLUSIONS: This study furnishes crucial insights into the molecular epidemiology of HBV, HCV, and HIV-1 co-infections in Ethiopia. The acquired knowledge can contribute to the advancement of strategies for clinical management and the formulation of public health interventions aimed at ameliorating the burden of viral infections within the nation.
Asunto(s)
Coinfección , Genotipo , Infecciones por VIH , VIH-1 , Hepacivirus , Virus de la Hepatitis B , Hepatitis B , Hepatitis C , Epidemiología Molecular , Humanos , Etiopía/epidemiología , Coinfección/epidemiología , Coinfección/virología , Hepatitis C/epidemiología , Hepatitis C/virología , Infecciones por VIH/epidemiología , Infecciones por VIH/virología , Hepatitis B/epidemiología , Hepatitis B/virología , Masculino , Adulto , Femenino , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/aislamiento & purificación , VIH-1/genética , VIH-1/clasificación , VIH-1/aislamiento & purificación , Adulto Joven , Hepacivirus/genética , Hepacivirus/clasificación , Hepacivirus/aislamiento & purificación , Adolescente , Persona de Mediana Edad , Prevalencia , Niño , Preescolar , Anciano , Lactante , Variación GenéticaRESUMEN
Although a combination of immunoprophylaxis and antiviral therapy can effectively prevent mother-to-child transmission (MTCT) of hepatitis B virus (HBV), a considerable number of infants born to highly viremic mothers still develop occult HBV infection (OBI). To uncover the virological factor and risk predictor for OBI in infants, we found that the diversity and complexity of maternal HBV quasispecies in the case group were lower than those in the control group. Mutations with significant differences between the two groups were most enriched in the NTCPbd and PreC regions. Genetic distance at the amino-acid level of the PreC region, especially the combination of three amino-acid mutations in the PreC region, could strongly predict the risk of OBI in infants. HBV quasispecies in OBI infants were highly complex, and the non-synonymous substitutions were mainly found in the RT and HBsAg regions. The sK47E (rtQ55R) and sP49L mutations in OBI infants might contribute to OBI through inhibiting the production of HBV DNA and HBsAg, respectively. This study found the potential virological factors and risk predictors for OBI in infants born to highly viremic mothers, which might be helpful for controlling OBI in infants.
Asunto(s)
ADN Viral , Virus de la Hepatitis B , Hepatitis B , Transmisión Vertical de Enfermedad Infecciosa , Mutación , Cuasiespecies , Viremia , Humanos , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/aislamiento & purificación , Femenino , Cuasiespecies/genética , Hepatitis B/virología , Hepatitis B/transmisión , ADN Viral/genética , Lactante , Embarazo , Adulto , Antígenos de Superficie de la Hepatitis B/genética , Antígenos de Superficie de la Hepatitis B/sangre , Recién Nacido , Complicaciones Infecciosas del Embarazo/virología , Masculino , Madres , GenotipoRESUMEN
Despite the availability of a vaccine against hepatitis B virus (HBV), this infection still causes public health problems, particularly in susceptible populations. In Portugal, universal free vaccination started in 1994, and most HBV infections are diagnosed in immigrants from high-prevalence countries. Our aim was to assess the pattern of HBV genotypes/subgenotypes in samples collected between 2017 and 2021 from a convenience sample of 70 infected residents in Portugal. The HBV pol/HBsAg region was amplified and sequenced, allowing the analysis of RT sequences submitted to phylogenetic analysis and mutations assessment. A total of 37.1% of samples were from native Portuguese, aged 25-53 years (mean: 36.7 years), and the remaining samples were from individuals born outside of Portugal. A high diversity of HBV was identified: subgenotypes A1-A3 in 41.0% (16/39); D1, D3, and D4 in 30.7% (12/39); E in 23.1% (9/39); and F4 in 2.6% (1/39). Besides genotypes A and D, Portuguese were also infected with genotypes E and F, which are prevalent in Africa and South America, respectively. Resistance mutations in RT sequences were not found. The findings provide valuable insights for updating the HBV molecular epidemiology in Portugal. However, successful strategies to prevent and control the infection are still needed in the country, especially among susceptible and vulnerable populations.
Asunto(s)
Genotipo , Vacunas contra Hepatitis B , Virus de la Hepatitis B , Hepatitis B , Filogenia , Vacunación , Humanos , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/inmunología , Adulto , Persona de Mediana Edad , Hepatitis B/virología , Hepatitis B/epidemiología , Hepatitis B/prevención & control , Femenino , Masculino , Portugal/epidemiología , Vacunas contra Hepatitis B/administración & dosificación , Vacunas contra Hepatitis B/inmunología , Mutación , Variación Genética , Antígenos de Superficie de la Hepatitis B/genética , Antígenos de Superficie de la Hepatitis B/sangre , ADN Viral/genética , Adulto JovenRESUMEN
Chronic infection of hepatitis B virus (HBV) and hepatitis D virus (HDV) causes the most severe form of viral hepatitis. Due to the dependence on HBV, HDV was deemed to co-evolve and co-migrate with HBV. However, we previously found that the naturally occurred HDV/HBV combinations do not always reflect the most efficient virological adaptation (Wang et al., 2021). Moreover, regions with heavy HBV burden do not always correlate with high HDV prevalence (e.g., East Asia), and vice versa (e.g., Central Asia). Herein, we systematically elucidated the spatiotemporal evolutionary landscape of HDV to understand the unique epidemic features of HDV. We found that the MRCA of HDV was from South America around the late 13th century, was globally dispersed mainly via Central Asia, and evolved into eight genotypes from the 19th to 20th century. In contrast, the MRCA of HBV was from Europe â¼23.7 thousand years ago (Kya), globally dispersed mainly via Africa and East Asia, and evolved into eight genotypes â¼1100 years ago. When HDV stepped in, all present-day HBV genotypes had already formed and its global genotypic distribution had stayed stable geographically. Nevertheless, regionalized HDV adapted to local HBV genotypes and human lineages, contributing to the global geographical separation of HDV genotypes. Additionally, a sharp increase in HDV infections was observed after the 20th century. In conclusion, HDV exhibited a distinct spatiotemporal distribution path compared with HBV. This unique evolutionary relationship largely fostered the unique epidemic features we observe nowadays. Moreover, HDV infections may continue to ramp up globally, thus more efforts are urgently needed to combat this disease.
Asunto(s)
Virus de la Hepatitis B , Hepatitis D , Virus de la Hepatitis Delta , Filogenia , Virus de la Hepatitis Delta/genética , Virus de la Hepatitis Delta/clasificación , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/clasificación , Humanos , Hepatitis D/epidemiología , Hepatitis D/virología , Evolución Molecular , Genotipo , Epidemias , Análisis Espacio-Temporal , Coinfección/virología , Coinfección/epidemiologíaRESUMEN
INTRODUCTION: This study aimed to investigate the differences between pregnant women with chronic hepatitis B virus (HBV) infection and intrafamilial infection and those without intrafamilial infection. METHODS: HBV-DNA was extracted from the sera of 16 pregnant women with chronic hepatitis B (CHB) and their family members for gene sequencing and phylogenetic analyses. A total of 74 pregnant women with CHB were followed up from the second trimester to 3 months postpartum. Viral markers and other laboratory indicators were compared between pregnant women with CHB with and without intrafamilial infection. RESULTS: The phylogenetic tree showed that HBV lines in the mother-spread pedigree shared a node, whereas there was an unrelated genetic background for HBV lines in individuals without intrafamilial infection. From delivery to 3 months postpartum, compared with those without intrafamilial infection, pregnant women with intrafamilial infection were related negatively to HBV-DNA (ß = -0.43, 95% confidence interval [CI]: -0.76 to -0.12, p = 0.009), HBeAg (ß = -195.15, 95% CI: -366.35 to -23.96, p = 0.027), and hemoglobin changes (ß = -8.09, 95% CI: -15.54 to -0.64, p = 0.035) and positively to changes in the levels of alanine aminotransferase (ß = 73.9, 95% CI: 38.92-108.95, p < 0.001) and albumin (ß = 2.73, 95% CI: 0.23-5.23, p = 0.033). CONCLUSION: The mother-spread pedigree spread model differs from that of non-intrafamilial infections. Pregnant women with intrafamilial HBV infection have less hepatitis flares and liver damage, but their HBV-DNA and HBeAg levels rebound faster after delivery, than those without intrafamilial infection by the virus.
Asunto(s)
ADN Viral , Virus de la Hepatitis B , Hepatitis B Crónica , Filogenia , Complicaciones Infecciosas del Embarazo , Humanos , Femenino , Embarazo , Hepatitis B Crónica/virología , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/clasificación , Adulto , ADN Viral/genética , ADN Viral/sangre , Complicaciones Infecciosas del Embarazo/virología , Antígenos e de la Hepatitis B/sangre , Adulto Joven , Transmisión Vertical de Enfermedad Infecciosa , Genotipo , Análisis de Secuencia de ADNRESUMEN
BACKGROUND: To analysis of quasispecies (QS) changes and high-frequency mutations in the BCP/PreC/C region of patients at different phases of hepatitis B virus (HBV) infection and provides novel biomarkers for the diagnosis of chronic hepatitis B (CHB) patients. METHODS: With the application of next-generation sequencing technology, we were able to sequence the HBV BCP/PreC/C regions in 40 patients, each at different phases of the HBV infection. The heterogeneity of QS and the frequency of mutations were calculated using MEGA 7 software. RESULTS: Our results show that the complexity and diversity of the BCP/PreC/C QS in HBeAg-positive CHB patients are significantly higher than those in HBeAg-positive chronic infection patients, while HBeAg-negative chronic infection patients had significantly higher QS complexity and diversity than HBeAg-negative CHB patients. In addition, HBeAg-negative patients showed reduced complexity but increased diversity compared with HBeAg-positive patients. Receiver operating characteristic curves showed that G1764A, C2102T, dN and complexity of QS could be used as potential biomarkers for diagnosing HBeAg-positive CHB, while the A2189C, dS and complexity of QS could be used as potential biomarkers for diagnosing HBeAg-negative chronic hepatitis. Finally, our study also found that G1896A and A2159G may be hotspot mutations affecting HBeAg seroconversion. CONCLUSION: Our research elucidates the evolution of HBV by analyzing QS heterogeneity and mutation patterns, offering novel serum biomarkers for enhancing clinical diagnosis and disease prognosis. This comprehensive approach sheds light on the intricate dynamics of HBV progression and paves the way for more precise medical interventions.
Asunto(s)
ADN Viral , Antígenos e de la Hepatitis B , Virus de la Hepatitis B , Hepatitis B Crónica , Secuenciación de Nucleótidos de Alto Rendimiento , Mutación , Cuasiespecies , Humanos , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/clasificación , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Hepatitis B Crónica/virología , Hepatitis B Crónica/sangre , Cuasiespecies/genética , Masculino , Femenino , Antígenos e de la Hepatitis B/sangre , Adulto , ADN Viral/genética , ADN Viral/sangre , Persona de Mediana Edad , Adulto Joven , Biomarcadores/sangre , GenotipoRESUMEN
Screening and linkage to care are essential to achieve viral hepatitis elimination before 2030. The accurate identification of endemic areas is important for controlling diseases with geographic aggregation. Viral activity drives prognosis of chronic hepatitis B and hepatitis C virus infection. This screening was conducted in Chiayi County from 2018-2019. All residents aged 30 years or older were invited to participate in quantitative HBsAg (qHBsAg) and HCV Ag screening. Among the 4010 participants (male:female = 1630:2380), the prevalence of qHBsAg and HCV Ag was 9.9% (396/4010) and 4.1% (163/4010), respectively. High-prevalence townships were identified, three for qHBsAg > 15% and two for HCV Ag > 10%. The age-specific prevalence of qHBsAg was distributed in an inverse U-shape with a peak (16.0%, 68/424) for subjects in their 40 s; for HCV, prevalence increased with age. Concentrations of qHBsAg < 200 IU/mL were found in 54% (214/396) of carriers. The rate of oral antiviral treatment for HCV was 75.5% (114/151), with subjects younger than 75 years tending to undergo treatment (85.6% vs. 57.4%, p < 0.001). QHBsAg and HCV Ag core antigens can reflect the concentration of the viral load, which serves as a feasible screening tool. Using quantitative antigen screening for hepatitis B and C in community-based screening, two hyperendemic townships were identified from an endemic county.
Asunto(s)
Hepacivirus/aislamiento & purificación , Antígenos de la Hepatitis/sangre , Virus de la Hepatitis B/aislamiento & purificación , Hepatitis B/virología , Hepatitis C/virología , Adulto , Anciano , Anciano de 80 o más Años , Antivirales/uso terapéutico , ADN Viral/genética , Femenino , Hepacivirus/clasificación , Hepacivirus/genética , Hepacivirus/inmunología , Antígenos de la Hepatitis/inmunología , Hepatitis B/sangre , Hepatitis B/tratamiento farmacológico , Hepatitis B/epidemiología , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/inmunología , Hepatitis C/sangre , Hepatitis C/tratamiento farmacológico , Hepatitis C/epidemiología , Humanos , Masculino , Tamizaje Masivo , Persona de Mediana Edad , Prevalencia , Taiwán/epidemiologíaRESUMEN
The aim of our study was to determine the distribution of hepatitis B virus (HBV) genotypes and subgenotypes in ethnic minorities in Yunnan province to provide evidence supporting the theoretical basis for hepatitis B prevention and control. We obtained serum samples and demographic data from 765 individuals reported by Yunnan province who had either acute or chronic HBV infection and were from one of 20 ethnic minority populations: Achang, Bai, Brown, Tibetan, Dai, Deang, Dulong, Hani, Hui, Jingpo, Lahu, Yi, Lisu Miao, Naxi, Nu, Pumi, Wa, Yao, or Zhuang people. We sequenced the HBV DNA and determined the genotypes and subgenotypes of the isolated HBVs. We mapped the genotype and subgenotype distribution by ethnic minority population and conducted descriptive analyses. There were four genotypes among the 20 ethnic groups: genotype B (21.3% of samples), C (76.6%), D (1.8%) and I (0.3%). The most common subgenotype was C1. There were no genotype differences by gender (P = 0.954) or age (P = 0.274), but there were differences by region (P < 0.001). There were differences in genotype distribution (P < 0.001) and subgenotype distribution (P = 0.011) by ethnic group. Genotype D was most prominent in Tibet and most HBV isolates were C/D recombinant viruses. The only two genotype I virus isolates were in Zhuang people. Susceptibility and geographic patterns may influence HBV prevalence in different ethnic populations, but additional research is needed for such a determination.
Asunto(s)
Minorías Étnicas y Raciales/estadística & datos numéricos , Virus de la Hepatitis B/genética , Hepatitis B/epidemiología , Adulto , China/epidemiología , ADN Viral/genética , Femenino , Genotipo , Hepatitis B/etnología , Antígenos de Superficie de la Hepatitis B/genética , Virus de la Hepatitis B/clasificación , Humanos , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Filogenia , Prevalencia , Adulto JovenRESUMEN
Epidemiological data on hepatitis B virus (HBV) are needed to benchmark HBV elimination goals. We recently assessed prevalence of HBV infection and determinants in participants attending the Emergency Department in Paramaribo, Suriname, South America. Overall, 24.5% (95%CI = 22.7-26.4%) of participants had anti-Hepatitis B core antibodies, which was associated with older age (per year, adjusted Odds Ratio [aOR] = 1.03, 95%CI = 1.02-1.04), Afro-Surinamese (aOR = 1.84, 95%CI = 1.52-2.19) and Javanese ethnicity (aOR = 1.63, 95%CI = 1.28-2.07, compared to the grand mean). 3.2% of participants were Hepatitis B surface Ag-positive, which was also associated with older age (per year, aOR = 1.02, 95%CI = 1.00-1.04), Javanese (aOR = 4.3, 95%CI = 2.66-6.95) and Afro-Surinamese ethnicity (aOR = 2.36, 95%CI = 1.51-3.71). Sex, nosocomial or culturally-related HBV transmission risk-factors were not associated with infection. Phylogenetic analysis revealed strong ethnic clustering: Indonesian subgenotype HBV/B3 among Javanese and African subgenotypes HBV/A1, HBV/QS-A3 and HBV/E among Afro-Surinamese. Testing for HBV during adulthood should be considered for individuals living in Suriname, specifically with Javanese and Afro-Surinamese ancestry.
Asunto(s)
Virus de la Hepatitis B/genética , Hepatitis B/etnología , Hepatitis B/epidemiología , Adulto , Etnicidad , Femenino , Genotipo , Hepatitis B/virología , Anticuerpos contra la Hepatitis B/sangre , Antígenos del Núcleo de la Hepatitis B/inmunología , Antígenos de Superficie de la Hepatitis B/sangre , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/inmunología , Humanos , Masculino , Persona de Mediana Edad , Filogenia , Prevalencia , Factores de Riesgo , Suriname/epidemiología , Proteínas Virales/genéticaRESUMEN
Hepatitis B virus (HBV) has been infecting humans for millennia and remains a global health problem, but its past diversity and dispersal routes are largely unknown. We generated HBV genomic data from 137 Eurasians and Native Americans dated between ~10,500 and ~400 years ago. We date the most recent common ancestor of all HBV lineages to between ~20,000 and 12,000 years ago, with the virus present in European and South American hunter-gatherers during the early Holocene. After the European Neolithic transition, Mesolithic HBV strains were replaced by a lineage likely disseminated by early farmers that prevailed throughout western Eurasia for ~4000 years, declining around the end of the 2nd millennium BCE. The only remnant of this prehistoric HBV diversity is the rare genotype G, which appears to have reemerged during the HIV pandemic.
Asunto(s)
Enfermedades Transmisibles Emergentes/historia , Evolución Molecular , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/genética , Hepatitis B/historia , Américas , Asia , Pueblo Asiatico , Enfermedades Transmisibles Emergentes/virología , Europa (Continente) , Variación Genética , Genómica , Hepatitis B/virología , Historia Antigua , Humanos , Paleontología , Filogenia , Población Blanca , Indio Americano o Nativo de AlaskaRESUMEN
Occult Hepatitis B Infection (OBI) is a critical risk factor for triggering post-transfusion hepatitis (PTH), cirrhosis, hepatocellular carcinoma, and hepatitis B virus (HBV) reactivation, which ß-thalassemia major (BTM) patients are at risk of it due to multiple blood transfusions. This study was aimed at determining the prevalence of OBI among BTM patients from Khuzestan Province, Iran. In this cross-sectional study, 90 thalassemia patients, who have received blood 36 to 552 times, participated referred to the Shafa hospital of Ahvaz city from January 2018 to April 2019. ELISA for determining serological markers (HBsAg, anti-HBc, anti-HBs, and anti-HCV) and real-time PCR for detecting HBV-DNA were performed; Nested PCR was conducted for DNA sequencing and determining the genotype of OBI case. Phylogenetic and statistical analyses were done by R package. Of 90 subjects enrolled in this study; 95.5% (86/90) were HBsAg negative, and the frequency of OBI among them was 1.16% (1/86). The anti-HBs, anti-HBc, and anti-HCV were detected in 80.00%, 7.78%, and 12.2% of patients, respectively. HBV-DNA was assessed at four HBsAg-positive subjects as well, and all of them were negative. The phylogenetic analysis showed that the detected HBV DNA in the OBI case belongs to the genotype D. This research, for the first time, demonstrated that OBI is present among ß-thalassemia patients in Iran. Also, further studies are necessary to determine the actual prevalence of OBI among BTM patients in Iran to decisions concerning OBI screening, especially in transfusion centers.
Asunto(s)
Hepatitis B/complicaciones , Talasemia beta/complicaciones , Adolescente , Adulto , Secuencia de Aminoácidos , Secuencia de Bases , Transfusión Sanguínea/estadística & datos numéricos , Niño , Preescolar , Secuencia de Consenso , Estudios Transversales , ADN Viral/análisis , ADN Viral/química , Electroforesis en Gel de Agar , Femenino , Hepatitis B/epidemiología , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/genética , Humanos , Irán/epidemiología , Masculino , Persona de Mediana Edad , Filogenia , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Adulto Joven , Talasemia beta/terapiaRESUMEN
BACKGROUND: Telbivudine (LdT) - a synthetic thymidine ß-L-nucleoside analogue (NA) - is an effective inhibitor for hepatitis B virus (HBV) replication. The quasispecies spectra in the reverse transcriptase (RT) region of the HBV genome and their dynamic changes associated with LdT treatment remains largely unknown. METHODS: We prospectively recruited a total of 21 treatment-naive patients with chronic HBV infection and collected sequential serum samples at five time points (baseline, weeks 1, 3, 12, and 24 after LdT treatment). The HBV RT region was amplified and shotgun-sequenced by the Ion Torrent Personal Genome Machine (PGM)® system. We reconstructed full-length haplotypes of the RT region using an integrated bioinformatics framework, including de novo contig assembly and full-length haplotype reconstruction. In addition, we investigated the quasispecies' dynamic changes and evolution history and characterized potential NAs resistant mutations over the treatment course. RESULTS: Viral quasispecies differed obviously between patients with complete (n = 8) and incomplete/no response (n = 13) at 12 weeks after LdT treatment. A reduced dN/dS ratio in quasispecies demonstrated a selective constraint resulting from antiviral therapy. The temporal clustering of sequential quasispecies showed different patterns along with a 24-week observation, although its statistic did not differ significantly. Several patients harboring pre-existing resistant mutations showed different clinical responses, while NAs resistant mutations were rare within a short-term treatment. CONCLUSION: A complete profile of quasispecies reconstructed from in-depth shotgun sequencing may has important implications for enhancing clinical decision in adjusting antiviral therapy timely.
Asunto(s)
Virus de la Hepatitis B/efectos de los fármacos , Hepatitis B Crónica/tratamiento farmacológico , Cuasiespecies/efectos de los fármacos , ADN Polimerasa Dirigida por ARN/efectos de los fármacos , Telbivudina/uso terapéutico , Adulto , Antivirales/farmacología , Farmacorresistencia Viral , Femenino , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/genética , Hepatitis B Crónica/virología , Humanos , Masculino , Mutación/efectos de los fármacos , Inhibidores de la Síntesis del Ácido Nucleico , Estudios Prospectivos , Cuasiespecies/genética , ADN Polimerasa Dirigida por ARN/genética , Adulto JovenRESUMEN
Variants in the small surface gene of hepatitis B virus (HBV), which codes for viral surface antigen (HBsAg), can affect the efficacy of HBsAg screening assays and can be associated with occult HBV infection (OBI). This study aimed to characterise the molecular diversity of the HBV small surface gene from HBV-reactive Australian blood donors. HBV isolates from 16 HBsAg-positive Australian blood donors' plasma were sequenced and genotyped by phylogenies of viral coding genes and/or whole genomes. An analysis of the genetic diversity of eight HBV small surface genes from our 16 samples was conducted and compared with HBV sequences from NCBI of 164 international (non-Australian) blood donors. Genotypes A-D were identified in our samples. The region of HBV small surface gene that contained the sequence encoding the 'a' determinant had a greater genetic diversity than the remaining part of the gene. No escape mutants or OBI-related variants were observed in our samples. Variant call analysis revealed two samples with a nucleotide deletion leading to truncation of polymerase and/or large/middle surface amino acid sequences. Overall, we found that HBV small surface gene sequences from Australian donors demonstrated a lower level of genetic diversity than those from non-Australian donor population included in the study.
Asunto(s)
Donantes de Sangre , Variación Genética , Genotipo , Antígenos de Superficie de la Hepatitis B/genética , Virus de la Hepatitis B/genética , Australia/epidemiología , Donantes de Sangre/estadística & datos numéricos , ADN Viral/genética , Hepatitis B/epidemiología , Hepatitis B/virología , Virus de la Hepatitis B/clasificación , Humanos , MutaciónRESUMEN
As the global effort to eradicate hepatitis B continues, immune escape mutations (IEMs) and drug resistance mutations (DRMs) affecting its diagnosis, treatment, and prevention are compromising this goal. However, knowledge about the prevalence and circulation of these mutations in Nigeria is scarce. Serum samples (n = 199) from apparently healthy prospective blood donors, pregnant women, and individuals presenting with fever in southwestern Nigeria were analyzed for the presence of IEMs and DRMs by means of nested PCR in the HBV S (HBs) and HBV polymerase (Pol) genes, followed by phylogenetic and mutational analyses. In total, 25.1% (n = 50/199) of samples were positive for HBV, as measured by PCR. In 41 samples (20.6%), both fragments could be amplified, whereas the HBs gene and the Pol gene fragment alone were detected in 0.5% (n = 1/199) and 4% (n = 8/199) of samples, respectively. Sequences were successfully obtained for all 42 HBs gene fragments but for only 31/49 Pol gene fragments (totaling 73 sequences from 44 individuals). All sequences were identified as HBV genotype E. IEMs were present in 18.2% (n = 8/44) of the sequences of HBV-positive individuals with available sequences. IEM Q129H was detected in eight out of the 44 (18.2%) HBV isolates sequenced in this study; however, no DRMs were observed. This study confirms the circulation of HBV IEMs and reports the presence of Q129H IEM for the first time in Nigeria. Intensified research on the dynamics of IEM is necessary in order to enhance the elimination of HBV.
Asunto(s)
Virus de la Hepatitis B/genética , Virus de la Hepatitis B/inmunología , Hepatitis B/epidemiología , Evasión Inmune/genética , Mutación , Adolescente , Adulto , Niño , ADN Viral/genética , Femenino , Productos del Gen pol/genética , Genotipo , Hepatitis B/sangre , Hepatitis B/inmunología , Hepatitis B/virología , Antígenos de Superficie de la Hepatitis B/genética , Virus de la Hepatitis B/clasificación , Humanos , Masculino , Persona de Mediana Edad , Nigeria/epidemiología , Filogenia , Embarazo , Prevalencia , Estudios Prospectivos , Adulto JovenRESUMEN
The immunopathogenesis and molecular mechanisms involved during a hepatitis B virus (HBV) infection have made the approaches for research complex, especially concerning the patients' responses in the course of the early acute stage. The study of molecular bases involved in the viral clearance or persistence of the infection is complicated due to the difficulty to detect patients at the most adequate points of the disease, especially in the time lapse between the onset of the infection and the viral emergence. Despite this, there is valuable data obtained from animal and in vitro models, which have helped to clarify some aspects of the early immune response against HBV infection. The diversity of the HBV (genotypes and variants) has been proven to be associated not only with the development and outcome of the disease but also with the response to treatments. That is why factors involved in the virus evolution need to be considered while studying hepatitis B infection. This review brings together some of the published data to try to explain the immunological and molecular mechanisms involved in the different stages of the infection, clinical outcomes, viral persistence, and the impact of the variants of HBV in these processes.
Asunto(s)
Variación Genética , Genotipo , Virus de la Hepatitis B/genética , Hepatitis B Crónica/inmunología , Hepatitis B/inmunología , Animales , Hepatitis B/genética , Hepatitis B/patología , Hepatitis B/virología , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/inmunología , Hepatitis B Crónica/genética , Hepatitis B Crónica/patología , Hepatitis B Crónica/virología , Humanos , Replicación Viral/genética , Replicación Viral/inmunologíaRESUMEN
The mouse is not a natural host of hepatitis B virus (HBV) infection and - despite engraftment of hepatocytes with the HBV receptor - does not support formation of HBV covalently closed circular (ccc) DNA serving as a template for viral transcription and permitting persistent infection. In a recent study, cccDNA formation in mouse hepatocytes has been described following an HBV genome delivery by a recombinant, adeno-associated virus vector (rAAV) (Lucifora et al., 2017). The integrity of HBV cccDNA, its origin and functionality, however, remained open. In this study, we investigated the identity, origin, and functionality of cccDNA established in mice infected with rAAV carrying 1.3-fold overlength HBV genomes. We show that replication of HBV genotypes A, B, C and D can be initiated in mouse livers, and that cccDNA derived from all genotypes is detected. Restriction enzyme and exonuclease digestion as well as sequencing analysis of cccDNA amplicons revealed authentic HBV cccDNA without any detectable alteration compared to cccDNA established after HBV infection of human liver cells. Mouse livers transduced with a core protein-deficient HBV using rAAV still supported cccDNA formation demonstrating that the genesis of cccDNA was independent of HBV replication. When mice were infected with an rAAV-HBV1.3 carrying premature stop codons in the 5' but not in the 3' core protein open reading frame, the stop codon was partially replaced by the wild-type sequence. This strongly indicated that intramolecular recombination, based on >900 identical base pairs residing at the both ends of the HBV1.3 transgene was the origin of cccDNA formation. Accordingly, we observed a constant loss of cccDNA molecules from mouse livers over time, while HBeAg levels increased over the first two weeks after rAAV-HBV1.3 infection and remained constant thereafter, suggesting a minor contribution of the cccDNA molecules formed to viral transcription and protein expression. In summary, our results provide strong evidence that intramolecular recombination of an overlength, linear HBV genome, but not HBV genome recycling, enables cccDNA formation in rAAV-HBV mouse models.
Asunto(s)
ADN Circular/genética , Dependovirus/genética , Genoma Viral , Virus de la Hepatitis B/genética , Hígado/virología , Recombinación Genética , Replicación Viral/genética , Animales , Replicación del ADN , ADN Viral/genética , Vectores Genéticos , Genotipo , Células Hep G2 , Virus de la Hepatitis B/clasificación , Humanos , Masculino , Ratones , Ratones Endogámicos C57BLRESUMEN
Little is known about the usefulness of saliva samples for hepatitis B virus (HBV) genotyping and mutation analysis. The aim of this study was to evaluate the usefulness of oral fluid samples to determine HBV genotype distribution, S/polymerase mutations, and HBV subpopulation diversity among chronically HBV-infected individuals. Serum and oral fluid samples were obtained from 18 individuals for PCR and nucleotide sequencing of the HBV surface antigen gene. Biochemical analysis of liver enzymes (ALT, AST, GGT) and HBV, HCV, and HIV serological tests were also performed. All serum samples were HBsAg (+), anti-HBc (+), and anti-HBs (-); 55.6% were HBeAg (+)/anti-HBe (-), and 11.1% were anti-HIV (+). The mean HBV DNA viral load was 6.1 ± 2.3 log IU/mL. The HBV genotype distribution was as follows: A, 72.2%; D, 11.1%; E, 5.6%; F, 11.1%. A concordance of 100% in genotype classification and 99.8% in sequence similarity between paired oral fluid and serum samples was observed. HBsAg mutations were detected in all samples, but no resistance mutations were found in the polymerase gene. This study demonstrates that oral fluid samples can be used reliably for tracking HBV mutations, genotyping, and phylogenetic analysis. This could be important for molecular epidemiology studies with hard-to-reach populations.
Asunto(s)
Genotipo , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/genética , Mutación , Filogenia , Adulto , Secuencia de Bases , ADN Viral/sangre , ADN Viral/genética , Femenino , Hepatitis B/virología , Anticuerpos contra la Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/sangre , Antígenos e de la Hepatitis B/sangre , Hepatitis B Crónica/virología , Humanos , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Pruebas SerológicasRESUMEN
The dried blood spot (DBS) samples are a useful resource for viral DNA isolation and important in increasing access to HBV diagnosis. However, the choice of the DNA extraction method is crucial for reliable results. We compared the reliability of four DNA extraction methods using DBS samples for the qualitative and quantitative detection of HBV. A panel of serially diluted HBV DNA in whole blood was spotted onto filter paper (Whatman 903 paper and Whatman FTA cards). Four methods were used to extract DNA: QIAamp® DNA Blood Mini Kit (Qiagen); High Pure Viral Nucleic Acid Kit (Roche); Invisorb Spin Blood Midi Kit (Invitek), and DBS Genomic DNA Isolation Kit (Norgen Biotek). Two qualitative PCRs for the core and surface gene regions of HBV were used, and in-house real-time PCR was also evaluated. It was possible to detect HBV DNA using all extraction and PCR protocols. The lowest limit of detection was found using Whatman 903 paper, Roche extraction, and qualitative PCR (20 copies of HBV DNA per ml) for the surface/polymerase HBV region. In the case of in-house real-time PCR, the lowest limit of detection was found using both Roche and Qiagen assays (estimated 2 × 103 copies per ml). These results suggest the importance of both the extraction method and PCR protocol in detecting HBV DNA in DBS. This study provides insights into the utility of DBS samples in HBV molecular diagnosis and their feasibility in low resource areas where cold storage and transportation may be difficult.