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1.
Science ; 374(6564): 182-188, 2021 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-34618559

RESUMEN

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 Alaska
2.
Antivir Ther ; 24(4): 237-246, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30882363

RESUMEN

BACKGROUND: A unique chronic hepatitis B patient was followed over 189 months of nucleoside/nucleotide analogue (NA) therapies with the analysis of multiple drug-resistance HBV mutants. METHODS: Clonal sequencing (≥20 clones/sample) was performed on sera sampled at 41 time points, and the phenotypic features of eight representative mutants were analysed. RESULTS: Lamivudine (LAM)-, adefovir dipivoxil (ADV)-, entecavir (ETV)- and repeat ADV-resistance mutants emerged upon individual sequential NA monotherapy. The efficacy of NA combination rescue therapies ranked as LAM+ADV < ETV+ADV < ETV+ tenofovir disoproxil fumarate (TDF). Specifically, LAM+ADV and ETV+ADV suppressed viral loads to <100 IU/ml for a long period of time, either with or without late stage HBV DNA fluctuations. Furthermore, ETV+TDF suppressed the viral load to <10 IU/ml. During the LAM+ADV and ETV+ADV combination therapies, ETV-resistance mutants dominated at most time points, and multidrug-resistance (MDR) mutants that harboured LAM-, ETV- and ADV-resistance mutations were intermittently detected. Interestingly, the rtA181T-causative sW172stop to sW172non-stop mutation transition was observed at HBV DNA fluctuations. In a phenotypic analysis, two MDR strains had cross-resistance to LAM, ETV and ADV, and a lower susceptibility to TDF (<10-fold decrease compared with the wild-type strain). In contrast, the natural replication capacity was inversely associated with the number of primary resistant mutations which would limit MDR mutant development. CONCLUSIONS: Taken together, viral drug susceptibility, replication capacity, and perhaps immunological adaptation may play coordinated roles in the fitness of drug-resistance mutants. ETV+TDF therapy is the preferred option for treating chronic hepatitis B patients with multiple drug failure.


Asunto(s)
Antivirales/uso terapéutico , Farmacorresistencia Viral , Antígenos de Superficie de la Hepatitis B/genética , Virus de la Hepatitis B/efectos de los fármacos , Virus de la Hepatitis B/genética , Hepatitis B/tratamiento farmacológico , Hepatitis B/virología , Mutación , Adulto , Sustitución de Aminoácidos , Antivirales/farmacología , Biomarcadores , Clonación Molecular , Quimioterapia Combinada , Evolución Molecular , Genotipo , Hepatitis B/diagnóstico , Virus de la Hepatitis B/clasificación , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Filogenia , Resultado del Tratamiento , Carga Viral , Replicación Viral/efectos de los fármacos
3.
Nature ; 557(7705): 418-423, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29743673

RESUMEN

Hepatitis B virus (HBV) is a major cause of human hepatitis. There is considerable uncertainty about the timescale of its evolution and its association with humans. Here we present 12 full or partial ancient HBV genomes that are between approximately 0.8 and 4.5 thousand years old. The ancient sequences group either within or in a sister relationship with extant human or other ape HBV clades. Generally, the genome properties follow those of modern HBV. The root of the HBV tree is projected to between 8.6 and 20.9 thousand years ago, and we estimate a substitution rate of 8.04 × 10-6-1.51 × 10-5 nucleotide substitutions per site per year. In several cases, the geographical locations of the ancient genotypes do not match present-day distributions. Genotypes that today are typical of Africa and Asia, and a subgenotype from India, are shown to have an early Eurasian presence. The geographical and temporal patterns that we observe in ancient and modern HBV genotypes are compatible with well-documented human migrations during the Bronze and Iron Ages1,2. We provide evidence for the creation of HBV genotype A via recombination, and for a long-term association of modern HBV genotypes with humans, including the discovery of a human genotype that is now extinct. These data expose a complexity of HBV evolution that is not evident when considering modern sequences alone.


Asunto(s)
Evolución Molecular , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/aislamiento & purificación , Hepatitis B/virología , Filogenia , África , Animales , Asia , Europa (Continente) , Genotipo , Virus de la Hepatitis B/clasificación , Historia Antigua , Historia Medieval , Hominidae/virología , Migración Humana/historia , Humanos , Recombinación Genética
4.
Microb Drug Resist ; 23(4): 516-522, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27792585

RESUMEN

The study aimed to investigate the association of prevalent genotypes in China (HBV/C and HBV/B) with HBV drug-resistant mutations. A total of 13,847 nucleos(t)ide analogue (NA)-treated patients with chronic HBV infection from North China were enrolled. HBV genotypes and resistant mutations were determined by direct sequencing and confirmed by clonal sequencing if necessary. HBV/B, HBV/C, and HBV/D occupied 14.3%, 84.9%, and 0.8% across the study population, respectively. NA usage had no significant difference between HBV/B- and HBV/C-infected patients. Lamivudine-resistant mutations were more frequently detected in HBV/C-infected patients, compared with HBV/B-infected patients (31.67% vs. 25.26%, p < 0.01). Adefovir- and entecavir-resistant mutation detection rates were similar, but the mutational pattern was different between the two genotypes. For adefovir-resistant mutations, HBV/C-infected patients had a higher detection rate of rtA181 V (HBV/C 5.29% vs. HBV/B 1.36%, p < 0.01) and a lower detection rate of rtN236T (2.70% vs. 6.54%, p < 0.01). For entecavir-resistant mutations, HBV/C-infected patients had a higher detection rate of rtM204 V/I+T184 substitution or S202G/C (3.66% vs. 2.16%, p < 0.01) and a lower detection rate of rtM204 V/I+M250 V/I/L substitution (0.67% vs. 1.46%, p < 0.01). Multidrug-resistant mutations (defined as coexistence of mutation to nucleoside and nucleotide analogues) were detected in 104 patients. HBV/C-infected patients had a higher detection rate of multidrug-resistant mutation than HBV/B-infected patients (0.83% vs. 0.35%, p < 0.05). The study for the first time clarified that HBV/C-infected patients had a higher risk to develop multidrug-resistant mutations, compared with HBV/B-infected patients; and HBV/C- and HBV/B-infected patients had different inclinations in the ETV-resistant mutational pattern.


Asunto(s)
Antivirales/uso terapéutico , Farmacorresistencia Viral Múltiple/genética , Virus de la Hepatitis B/genética , Hepatitis B Crónica/tratamiento farmacológico , Tasa de Mutación , Proteínas Virales/genética , Adenina/análogos & derivados , Adenina/uso terapéutico , Adulto , China , Estudios de Cohortes , Femenino , Expresión Génica , Genotipo , Guanina/análogos & derivados , Guanina/uso terapéutico , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/efectos de los fármacos , Virus de la Hepatitis B/aislamiento & purificación , Hepatitis B Crónica/virología , Humanos , Lamivudine/uso terapéutico , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Organofosfonatos/uso terapéutico , Filogenia
5.
J Virol Methods ; 110(1): 29-35, 2003 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-12757918

RESUMEN

A genotype-specific probes assay (GSPA) was developed for distinguishing the seven genotypes (A-G) of hepatitis B virus (HBV). Nucleotide (nt) sequences corresponding to preS1 region were amplified by PCR with a primer labeled with biotin, and delivered to eight wells on which complementary sequences specific to one or other genotype had been immobilized. Thereafter, hybridization of HBV DNA sequences amplified from the test serum was detected by colorimetry. When 256 sera from HBV carriers in Bangladesh, Cameroon, Japan, South Africa, USA and Uzbekistan were subjected to GSPA, genotypes were concordant with those of ELISA with monoclonal antibodies to epitopes on preS2-region products in 242 (94.6%) of them; 8 sera (3.1%) were not genotypeable by either method. Cloning analysis confirmed the presence of two distinct HBV genotypes in the seven selected sera with coinfection. There were 7 (2.7%) sera with discordant genotyping results between GSPA and ELISA. When HBV DNA clones propagated from these sera were sequenced and analyzed phylogenetically, the genotypes determined by GSPA were verified. Coinfection with HBV strains of two distinct genotypes was identified by GSPA in 28 (10.9%) sera, while it was suggested by ELISA in only 2 (0.8%) sera. The GSPA method would be particularly useful for detecting the coinfection with distinct HBV genotypes of any clinical relevance, which seems to be more frequent than reported previously.


Asunto(s)
Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/genética , Hepatitis B/complicaciones , Hepatitis B/virología , Hibridación de Ácido Nucleico/métodos , Sondas de Oligonucleótidos , Biotina , Ensayo de Inmunoadsorción Enzimática , Genotipo , Antígenos de Superficie de la Hepatitis B/genética , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , Precursores de Proteínas/genética , Análisis de Secuencia de ADN , Especificidad de la Especie
6.
Commun Dis Public Health ; 2(2): 137-40, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10402750

RESUMEN

A retrospective cohort serological study identified five confirmed cases of acute hepatitis B virus (HBV) infection in three and a half years at an acupuncture clinic in London. These cases made up 1.7% of those treated by an acupuncturist who was a hepatitis B 'e' antigen (HBeAg) carrier. Virus subtyping and polymerase chain reaction--single strand conformation polymorphism assay (PCR-SSCPA) showed that strains of virus from the acupuncturist and two of the five patients for whom it was possible to perform the test were indistinguishable. Nine other patients who attended the same acupuncturist had antibody to the hepatitis B core antigen but had other risk factors for HBV infection. No obvious mode of transmission was identified but cross contamination of needles could not be ruled out in two cases. The fifth case was exposed to HBV after disposable needles were introduced. Routine immunisation of acupuncturists against HBV is recommended.


Asunto(s)
Terapia por Acupuntura , Brotes de Enfermedades , Hepatitis B/epidemiología , Hepatitis B/transmisión , Transmisión de Enfermedad Infecciosa de Profesional a Paciente , Instituciones de Atención Ambulatoria , Portador Sano/diagnóstico , Portador Sano/virología , Estudios de Cohortes , Hepatitis B/virología , Antígenos e de la Hepatitis B/sangre , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/inmunología , Virus de la Hepatitis B/aislamiento & purificación , Humanos , Londres/epidemiología , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Estudios Retrospectivos
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