RESUMEN
The impact of hepatitis B virus (HBV) infection on the progression of coronavirus disease 2019 (COVID-19) disease remains controversial. We aimed to investigate whether pre-existing chronic HBV (CHB) infection and therapy with anti-HBV nucleos(t)ide analogs (NAs) influence the clinical presentation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant infection. In this study, clinical information was collected via a questionnaire from patients with COVID-19, and their clinical symptoms were quantitatively assessed for comparative analyses. Additionally, hepatitis B-related laboratory data were collected for CHB patients. Propensity score matching (PSM) was used to minimize confounding biases. A total of 785 patients with COVID-19 were included in the cohort, of which 387 were identified as being infected with CHB infection and they were categorized as being in the immune control or clearance phase. After PSM, the CHB group (n = 222) had a shorter duration of fever and disease course, milder clinical symptoms, and lower incidence of pneumonia than the non-CHB group (n = 222) after Omicron variant infection (p < 0.05). After the adjustment of confounding factors, CHB patients showed a lower risk of prolonged fever, severe clinical symptoms, and pneumonia (p < 0.05). However, there were no statistically significant differences in the clinical symptoms and incidence of pneumonia between CHB patients who received and did not receive NAs, or CHB patients who received tenofovir disoproxil fumarate and entecavir (p > 0.05). In conclusion, our findings suggest that the crosstalk of anti-HBV immunity may contribute to the alleviated symptoms of SARS-CoV-2 Omicron variants infection in the CHB patients, independent of anti-HBV NA therapy.
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COVID-19 , Hepatitis B Crónica , Humanos , Hepatitis B Crónica/complicaciones , Hepatitis B Crónica/tratamiento farmacológico , Hepatitis B Crónica/diagnóstico , SARS-CoV-2 , Antivirales/uso terapéutico , Virus de la Hepatitis BRESUMEN
INTRODUCTION AND OBJECTIVES: The optimal blood pressure (BP) range for patients with metabolic dysfunction-associated fatty liver disease (MAFLD) is currently unknown. This study aimed to explore the relationship between stratified BP levels and MAFLD progression. PATIENTS AND METHODS: The data of adults who underwent yearly health check-ups were screened to establish both a cross-sectional and a 6-year longitudinal cohort of individuals with MAFLD. BP was classified into the following categories optimal, normal, high-normal, and hypertension. Liver fibrosis was diagnosed with fibrosis-4 (FIB-4) score, nonalcoholic fatty liver disease fibrosis score (NFS), and aspartate aminotransferase-to-platelet ratio index (APRI). RESULTS: A total of 10,232 individuals were included in the cross-sectional cohort. In the MAFLD population, individuals with liver fibrosis had significantly higher BP levels and hypertension prevalence (P < 0.001) than those without. Furthermore, liver fibrosis score was significantly associated with BP levels (P < 0.001). In the 6-year longitudinal cohort of 3661 individuals with MAFLD without liver fibrosis, the incidence rates of liver fibrosis increased with increasing BP levels as follows optimal=11.20%, normal=13.90%, high-normal=19.50%, hypertension=26.20% (log-rank 22.205; P < 0.001). Cox regression analysis showed that both baseline high-normal BP (hazard ratio [HR], 1.820; P=0.019) and hypertension (HR, 2.656; P < 0.001) were predictive of liver fibrosis. CONCLUSIONS: BP stratification may be useful in predicting the progression of MAFLD. Individuals having MAFLD with concurrent hypertension or high-normal BP are at a higher risk of liver fibrosis. These findings may provide a criteria for early intervention of MAFLD to prevent liver fibrosis.
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Hipertensión , Enfermedad del Hígado Graso no Alcohólico , Adulto , Humanos , Presión Sanguínea , Estudios Transversales , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Hipertensión/diagnóstico , Hipertensión/epidemiología , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/epidemiologíaRESUMEN
Hepatitis B virus (HBV) is a common viral pathogen that infects more than a third of the world's population; however, the transmission route remains to be further defined. The 18-year implementation of the free HBV vaccine for children has greatly changed the prevalence of HBV infection in China, which presents a unique real-world model for assessing the pattern of HBV transmission. Cross-sectional data of HBV seromarkers between July 2019 and April 2020 were collected from 53 371 individuals aged 1-60 years in four areas of North to South in Eastern China. Longitudinal data of HBV seromarkers between 2007 and 2020 were collected from 177 adults in an area of South China. The regional- and age-specific changes in HBV seromarkers were analyzed. Overall, positive rates of HBV surface antigen (HBsAg; from 3.44% to 15.1%) and antibody against HBV core antigen (anti-HBc; from 7.6% to 44.0%) significantly increased from North to South. Among persons aged ≤18 years, the positive rates of antibody against HBsAg (anti-HBs) and anti-HBc (+) remained at low levels in the North, while they were increasing among persons aged >12 years in the South, despite higher positive rates of anti-HBs (+). Among persons aged >18 years, the anti-HBs (+) rates remained relatively stable (~60%), while anti-HBc (+) rates increased significantly with age. Up to ~80% of the anti-HBs (+) adults in the South was anti-HBc (+) while it was 13.6% in the North. In the longitudinal cohort, the anti-HBc (+) rate among adults in the South increased by 14.2% during 10 years of follow-up. Horizontal transmission might be a common route in highly endemic areas, and may help to explain the high HBV exposure worldwide. The risk of horizontal transmission among children without seroprotective anti-HBs should be notified in highly endemic areas.
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Virus de la Hepatitis B , Hepatitis B , Adulto , Niño , Estudios Transversales , Anticuerpos contra la Hepatitis B , Antígenos del Núcleo de la Hepatitis B , Antígenos de Superficie de la Hepatitis B , Vacunas contra Hepatitis B , Humanos , VacunaciónRESUMEN
Nucleos(t)ide analogues (NAs) have been widely used for the treatment of chronic hepatitis B (CHB). Because viral DNA polymerase lacks proofreading function (3' exonuclease activity), theoretically, the incorporated NAs would irreversibly terminate viral DNA synthesis. This study explored the natures of nascent hepatitis B virus (HBV) DNA and infectivity of progeny virions produced under NA treatment. HBV infectivity was determined by infection of HepG2-NTCP cells and primary human hepatocytes (PHHs). Biochemical properties of HBV DNA in the progeny virions were investigated by qPCR, northern blotting, or Southern blotting hybridization, sucrose gradient centrifugation, and in vitro endogenous DNA polymerase assay. Progeny HBV virions produced under NA treatment were mainly not infectious to HepG2-NTCP cells or PHHs. Biochemical analysis revealed that under NA treatment, HBV DNA in nucleaocapsids or virions were predominantly short minus-strand DNA with irreversible termination. This finding was supported by the observation of first disappearance of relaxed circular DNA and then the proportional decline of HBV-DNA levels corresponding to the regions of PreC/C, S, and X genes in serial sera of patients receiving NA treatment. Conclusion: HBV virions produced under NA treatment are predominantly replication deficient because the viral genomes are truncated and elongation of DNA chains is irreversibly terminated. Clinically, our results suggest that the viral loads of CHB patients under NA therapy vary with the different regions of genome being detected by qPCR assays. Our findings also imply that NA prevention of perinatal and sexual HBV transmission as well as infection of transplanted livers works not only by reducing viral loads, but also by producing noninfectious virions.
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ADN Viral/fisiología , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/patogenicidad , Hepatitis B Crónica/virología , Nucleósidos/uso terapéutico , Virión/genética , Virión/patogenicidad , Virus de la Hepatitis B/ultraestructura , Hepatitis B Crónica/tratamiento farmacológico , HumanosRESUMEN
As an emerging infectious disease, the clinical course and virological course of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection remain to be further investigated. In this case report, we described a case of SARS-CoV-2 infection with the clinical course for more than 2 months. This patient had recovered from pneumonia after treatment. The viral RNA of throat swabs became negative and the viral-specific antibodies were produced during the recovery period. However, the viral RNA reappeared and additionally persisted in throat swabs for more than 40 days. In addition, the viral RNA was detected in multiple types of specimens with extremely high titers in the saliva. In conclusion, these findings indicate that SARS-CoV-2 can cause a long clinical course. The coexistence of viral RNA and viral-specific antibodies may imply an immune evasion of SARS-CoV-2 from the host's immune system.
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COVID-19/diagnóstico , COVID-19/virología , ARN Viral , SARS-CoV-2/genética , Esparcimiento de Virus , Adulto , Biomarcadores , Manejo de la Enfermedad , Humanos , Masculino , Evaluación de Síntomas , Factores de Tiempo , Tomografía Computarizada por Rayos XRESUMEN
BACKGROUND: The serum alanine aminotransferase (ALT) level is a critical parameter for evaluating liver injury in non-alcoholic fatty liver disease (NAFLD). However, the currently accepted upper limits of normal (ULN) for serum ALT (ULN-ALT) are debated, as they may be excessively high. METHODS: A total of 1638 children aged 6-16 years, comprising 507 children with normal BMI (500 healthy children and 7 children with NAFLD), 199 overweight children, and 932 obese children, were included in the analysis. We re-evaluated the ULN-ALT in 500 healthy Chinese children using the 95th percentiles of serum ALT levels as revised ULN-ALT. Fatty liver was identified by ultrasound examination. RESULTS: Significant positive correlations between serum ALT levels and body mass index (BMI) were detected in overweight boys (r = .399, P < .001), obese boys (r = .398, P < .001), and obese girls (r = .392, P < .001). The prevalence percentages of NAFLD were 93.6%, 75.8%, and 37.9% in obese boys with serum ALT levels of >50, 25-50, and ≤25 U/L and were 81.6%, 67.9%, and 20.6% in obese girls with serum ALT levels of >40, 20-40, and ≤20 U/L, respectively. CONCLUSION: Serum ALT levels significantly correlated with abnormal BMI values in children, suggesting a rigorous BMI threshold is needed to establish the cutoffs for serum ULN-ALT in children. Besides, the revised serum ULN-ALT can uncover mild liver injury in obese children with NAFLD.
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Alanina Transaminasa/sangre , Enfermedad del Hígado Graso no Alcohólico/sangre , Obesidad/sangre , Adolescente , Índice de Masa Corporal , Niño , Femenino , Humanos , Masculino , Enfermedad del Hígado Graso no Alcohólico/diagnóstico por imagen , Enfermedad del Hígado Graso no Alcohólico/fisiopatología , Sobrepeso/sangre , Valores de Referencia , UltrasonografíaRESUMEN
BACKGROUND: The current upper limits of normal (ULN) for serum alanine aminotransferase (ALT) are increasingly challenged. We aimed to re-evaluate the ULN for ALT and assess the potential impact on the classification of natural course of chronic hepatitis B virus (HBV) infection in children. METHODS: Laboratory data obtained from three hospitals in China were retrospectively analysed. In total, 2054 children with chronic HBV infection and 8149 healthy children at age ≤18 years were included in the study. RESULTS: Age-specific and gender-specific ULNs for ALT, at averages of 30 U/L for boys and 24 U/L for girls, were calculated from the data of healthy children. Using the revised ULNs vs. the current ULNs (40-50 U/L), 31-60% vs. 9-17% of the 2054 HBV-infected children had an abnormal result as seen in their ALT baseline analysis, and the highest abnormality rate was seen in the infants. Data of 516 HBV-infected children were applied for the classification of clinical phase, 28.8% vs. 19.8% of the children were classified into the phases of hepatitis B e antigen (HBeAg-)positive/negative hepatitis. During a median follow-up of 62 months, 39 of 153 children underwent HBeAg seroconversion, whereas 3 of them had persistently "normal" ALT, according to the current ULN. CONCLUSIONS: The revision of ULN for ALT in children substantially impacts the classification of the natural course of chronic HBV infection. Mild ALT fluctuation is common during the stage childhood, suggesting a need to rethink the current conceptions of immune tolerance and natural course of chronic HBV infection in the children.
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Alanina Transaminasa/normas , Virus de la Hepatitis B/aislamiento & purificación , Hepatitis B Crónica/diagnóstico , Adolescente , Factores de Edad , Alanina Transaminasa/sangre , Niño , Preescolar , China , Femenino , Antígenos e de la Hepatitis B/sangre , Antígenos e de la Hepatitis B/aislamiento & purificación , Virus de la Hepatitis B/inmunología , Hepatitis B Crónica/sangre , Hepatitis B Crónica/inmunología , Hepatitis B Crónica/virología , Humanos , Lactante , Pruebas de Función Hepática/métodos , Pruebas de Función Hepática/normas , Masculino , Valores de Referencia , Estudios Retrospectivos , Factores SexualesRESUMEN
BACKGROUND: Higher hepatitis B surface antigen (HBsAg) facilitates hepatitis C virus (HCV) clearance in patients with hepatitis B virus (HBV)/HCV co-infection. We investigated the effect of exogenous HBsAg on the inhibition of HCV replication mediated by natural killer (NK) cells. METHODS: After isolated from peripheral blood of 42 chronic hepatitis B (CHB) patients and 16 healthy individuals, NK cells were co-cultured with HCV-infected Huh7 cells, respectively, with or without HBsAg. Three days later, the co-cultured supernatants were collected and HCV RNA levels were measured by real-time quantitative PCR. NKG2D, NKp46 and NKG2A expression levels were measured by flow cytometry. NKG2D on NK cells from CHB responsive subgroup was blocked and HCV RNA levels were examined again. RESULTS: HCV RNA levels in the co-cultured system were significantly reduced by NK cells isolated from healthy donors (Pâ¯<â¯0.01) but not from CHB patients. However, HCV RNA levels in CHB cultures were significantly decreased following HBsAg addition (Pâ¯<â¯0.05), whereas no such effect was seen in control cultures. No significant difference was observed in basic NKG2D expression between the CHB patients and healthy donors. On NK cells from CHB patients, the expression of NKG2D was increased significantly by HBsAg stimulation (Pâ¯<â¯0.01), and higher than that from healthy controls (Pâ¯<â¯0.05). HCV RNA levels were increased significantly after the blockage of NKG2D on NK cells from responsive CHB patients in the co-cultured system (Pâ¯<â¯0.05). CONCLUSION: Exogenous HBsAg stimulated NKG2D expression on NK cells from CHB patients which inhibit HCV replication, suggesting that HBsAg may facilitate the clearance of HCV in patients with HBV/HCV co-infection.
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Coinfección , Hepacivirus/metabolismo , Antígenos de Superficie de la Hepatitis B/metabolismo , Virus de la Hepatitis B/metabolismo , Hepatitis B Crónica/metabolismo , Hepatitis C/metabolismo , Células Asesinas Naturales/metabolismo , Subfamilia K de Receptores Similares a Lectina de Células NK/inmunología , Replicación Viral , Adulto , Estudios de Casos y Controles , Línea Celular Tumoral , Técnicas de Cocultivo , Femenino , Hepacivirus/genética , Hepacivirus/inmunología , Hepacivirus/patogenicidad , Antígenos de Superficie de la Hepatitis B/inmunología , Virus de la Hepatitis B/inmunología , Virus de la Hepatitis B/patogenicidad , Hepatitis B Crónica/inmunología , Hepatitis B Crónica/virología , Hepatitis C/inmunología , Hepatitis C/virología , Interacciones Huésped-Patógeno , Humanos , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/virología , Masculino , Persona de Mediana Edad , Subfamília C de Receptores Similares a Lectina de Células NK/metabolismo , Subfamilia K de Receptores Similares a Lectina de Células NK/metabolismo , Receptor 1 Gatillante de la Citotoxidad Natural/metabolismo , ARN Viral/biosíntesis , ARN Viral/genética , Transducción de Señal , Carga Viral , Adulto JovenRESUMEN
OBJECTIVE: HBV has two forms of genomic DNA, relaxed-circular DNA (rcDNA) and duplex-linear DNA (dlDNA). Compared to rcDNA, dlDNA has been demonstrated to integrate more frequently into host cellular chromosomes, which may have oncogenic consequences. However, the dlDNA proportion relative to total HBV DNA and its clinical significance in patients remain to be investigated. DESIGN: Based on the structural difference between rcDNA and dlDNA, we developed a peptide nucleic acid (PNA)-mediated quantitative real-time PCR (qPCR) clamping assay to measure the proportions of dlDNA in total HBV DNA in sera obtained from patients with chronic hepatitis B (CHB), liver cirrhosis (LC) or LC-developed hepatocellular carcinoma (HCC). The factors that influence the proportion of dlDNA were also investigated. RESULTS: The average dlDNA proportion was approximately 7% in the sera of chronic HBV-infected patients and was elevated in CHB patients with abnormal levels of alanine aminotransferase. The sera dlDNA proportions increased to approximately 14% and 20% in the patients with LC and HCC, respectively. Interferon-α treatment slightly increased the dlDNA proportion in the responders; and nucleotide analogue therapy spuriously elevated the proportion. Moreover, treatment of human hepatoma cells supporting HBV replication with inflammatory cytokines significantly altered the dlDNA proportion in vitro. CONCLUSIONS: Using a novel PNA-mediated qPCR clamping assay, we first showed that serum dlDNA proportions progressively increased during the development of HBV-related liver diseases. The dlDNA proportion can be regulated by inflammatory cytokines, suggesting an association among inflammation, increased production of HBV dlDNA and development of HCC.
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Carcinoma Hepatocelular/virología , ADN Viral/sangre , Virus de la Hepatitis B/genética , Hepatitis B Crónica/virología , Cirrosis Hepática/virología , Neoplasias Hepáticas/virología , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Hepatocelular/sangre , Carcinoma Hepatocelular/patología , Progresión de la Enfermedad , Femenino , Hepatitis B Crónica/sangre , Hepatitis B Crónica/patología , Humanos , Cirrosis Hepática/sangre , Cirrosis Hepática/patología , Neoplasias Hepáticas/sangre , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
BACKGROUND AND AIM: Alpha interferon (IFN-α) is an approved treatment for chronic hepatitis B (CHB). MicroRNA (miRNA) are currently known as a part of IFN-mediated antiviral defense. We aimed at characterizing the miRNA expression associated with hepatitis B virus (HBV) replication and IFN-mediated HBV clearance. METHODS: We investigated the expression patterns of cellular miRNA induced by HBV replication and/or IFN-α treatment in HepG2 cells, and also analyzed the miRNA response in peripheral blood mononuclear cells in CHB patients on IFN-α treatment. The differentially expressed miRNA were verified using quantitative real-time polymerase chain reaction and an miRNA expression pattern was classified based on the final virological response. RESULTS: A total of 223 miRNA were differentially expressed (> 1.5 folds) between the HepG2.2.15 and HepG2 cells, including 24 highly differentially expressed miRNA (> 5 folds). With 12 h of IFN-α treatment, 23 totally differentially expressed miRNA were identified in HepG2 cells; whereas only five miRNA were identified in HepG2.2.15 cells. Similar amounts of the miRNA were regulated in patients with HBeAg or non-HBeAg seroconversion; whereas levels of eight miRNA were significantly differentially expressed between the two groups. CONCLUSIONS: HBV replication alters miRNA expression profiles and impairs IFN-inducible miRNA response in HepG2 cells. The miRNA expression pattern of peripheral blood mononuclear cells in CHB patients with IFN therapy can be associated with their therapeutic outcome.
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Virus de la Hepatitis B/fisiología , Hepatitis B Crónica/sangre , Interferón-alfa/farmacología , Interferón-alfa/uso terapéutico , MicroARNs/sangre , MicroARNs/efectos de los fármacos , Polietilenglicoles/uso terapéutico , Replicación Viral , Adulto , Femenino , Células Hep G2 , Antígenos e de la Hepatitis B/sangre , Hepatitis B Crónica/tratamiento farmacológico , Humanos , Interferón alfa-2 , Leucocitos Mononucleares , Masculino , MicroARNs/metabolismo , Análisis por Micromatrices , Reacción en Cadena en Tiempo Real de la Polimerasa , Proteínas Recombinantes/farmacología , Proteínas Recombinantes/uso terapéutico , Resultado del Tratamiento , Adulto JovenRESUMEN
α-Glucosidases I and II are endoplasmic reticulum-resident enzymes that are essential for N-linked glycan processing and subsequent proper folding of glycoproteins. In this report, we first demonstrate that downregulation of the expression of α-glucosidase I, II, or both in Huh7.5 cells by small hairpin RNA technology inhibited the production of hepatitis C virus (HCV). In agreement with the essential role of α-glucosidases in HCV envelope glycoprotein processing and folding, treatment of HCV-infected cells with a panel of imino sugar derivatives, which are competitive inhibitors of α-glucosidases, did not affect intracellular HCV RNA replication and nonstructural protein expression but resulted in the inhibition of glycan processing and subsequent degradation of HCV E2 glycoprotein. As a consequence, HCV virion assembly and secretion were inhibited. In searching for imino sugars with better antiviral activity, we found that a novel imino sugar, PBDNJ0804, had a superior ability to inhibit HCV virion assembly and secretion. In summary, we demonstrated that glucosidases are important host factor-based antiviral targets for HCV infection. The low likelihood of drug-resistant virus emergence and potent antiviral efficacy of the novel glucosidase inhibitor hold promise for its development as a therapeutic agent for the treatment of chronic hepatitis C.
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Antivirales/farmacología , Retículo Endoplásmico/enzimología , Inhibidores Enzimáticos/farmacología , Inhibidores de Glicósido Hidrolasas , Hepacivirus/efectos de los fármacos , Virión/efectos de los fármacos , Línea Celular , Humanos , Ensamble de Virus/efectos de los fármacosRESUMEN
We screened â¼2,200 compounds known to be safe in people for the ability to reduce the amount of virion-associated hepatitis B virus (HBV) DNA in the culture medium of producer cells. These efforts led to the discovery of an alkylated porphyrin, chlorophyllide, as the compound that achieved the greatest reduction in signal. Here we report that chlorophyllide directly and quantitatively disrupted HBV virions at micromolar concentrations, resulting in the loss of all detectable virion DNA, without detectably affecting cell viability or intracellular viral gene products. Chemophores of chlorophyllide were also tested. Chlorin e6, a metal-free chlorophyllide-like molecule, showed the strongest antiviral activity against HBV as well as profound antiviral effects on other enveloped viruses, such as hepatitis C virus (HCV), human immunodeficiency virus (HIV), dengue virus (DENV), Marburg virus (MARV), Tacaribe virus (TCRV), and Junin viruses (JUNV). Remarkably, chlorin e6 inactivated DENV at subnanomolar-level concentrations. However, the compound had no antiviral effect against encephalomyocarditis virus and adenovirus, suggesting that chlorin e6 may be less active or inactive against nonenveloped viruses. Although other porphyrin derivatives have been previously reported to possess antiviral activity, this is the first analysis of the biochemical impact of chlorophyllide and chlorin e6 against HBV and of the dramatic anti-infectivity impact upon DENV. The possible application of this family of compounds as antiviral agents, as microbicides and systemic virus neutralizing agents, is discussed.
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Antivirales/farmacología , Arenavirus/efectos de los fármacos , Clorofilidas/farmacología , Filoviridae/efectos de los fármacos , Flavivirus/efectos de los fármacos , Hepadnaviridae/efectos de los fármacos , Porfirinas/farmacología , Arenavirus/clasificación , Virus del Dengue/efectos de los fármacos , Filoviridae/clasificación , Flavivirus/clasificación , Células Hep G2 , Hepadnaviridae/clasificación , Virus de la Hepatitis B/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana/métodos , Porfirinas/químicaRESUMEN
Tetherin and IFITM3 are recently identified interferon-induced cellular proteins that restrict infections by retroviruses and filoviruses and of influenza virus and flaviviruses, respectively. In our efforts to further explore their antiviral activities against other viruses and determine their antiviral mechanisms, we found that the two antiviral proteins potently inhibit the infection of vesicular stomatitis virus (VSV), a prototype member of the Rhabdoviridae family. Taking advantage of this well-studied virus infection system, we show that although both tetherin and IFITM3 are plasma membrane proteins, tetherin inhibits virion particle release from infected cells, while IFITM3 disrupts an early event after endocytosis of virion particles but before primary transcription of incoming viral genomes. Furthermore, we demonstrate that both the N-terminal 21 amino acid residues and C-terminal transmembrane region of IFITM3 are required for its antiviral activity. Collectively, our work sheds light on the mechanisms by which tetherin and IFITM3 restrict infection with rhabdoviruses and possibly other pathogenic viruses.
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Antígenos CD/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas de Unión al ARN/metabolismo , Estomatitis Vesicular/prevención & control , Estomatitis Vesicular/virología , Virus de la Estomatitis Vesicular Indiana/patogenicidad , Virión/fisiología , Replicación Viral/fisiología , Antígenos CD/genética , Northern Blotting , Western Blotting , Células Cultivadas , Endocitosis , Proteínas Ligadas a GPI/genética , Proteínas Ligadas a GPI/metabolismo , Genoma Viral , Humanos , Proteínas de la Membrana/genética , Mutación/genética , ARN Mensajero/genética , Proteínas de Unión al ARN/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transcripción Genética , Estomatitis Vesicular/genética , Internalización del VirusRESUMEN
Alpha interferon (IFN-alpha) is an approved medication for chronic hepatitis B. Gamma interferon (IFN-gamma) is a key mediator of host antiviral immunity against hepatitis B virus (HBV) infection in vivo. However, the molecular mechanism by which these antiviral cytokines suppress HBV replication remains elusive. Using an immortalized murine hepatocyte (AML12)-derived cell line supporting tetracycline-inducible HBV replication, we show in this report that both IFN-alpha and IFN-gamma efficiently reduce the amount of intracellular HBV nucleocapsids. Furthermore, we provide evidence suggesting that the IFN-induced cellular antiviral response is able to distinguish and selectively accelerate the decay of HBV replication-competent nucleocapsids but not empty capsids in a proteasome-dependent manner. Our findings thus reveal a novel antiviral mechanism of IFNs and provide a basis for a better understanding of HBV pathobiology.
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Virus de la Hepatitis B/inmunología , Interferón-alfa/inmunología , Interferón gamma/inmunología , Nucleocápside/metabolismo , Animales , Línea Celular , Hepatocitos/virología , Ratones , Complejo de la Endopetidasa Proteasomal/metabolismoRESUMEN
Interferons (IFNs) are key mediators of the host innate antiviral immune response. To identify IFN-stimulated genes (ISGs) that instigate an antiviral state against two medically important flaviviruses, West Nile virus (WNV) and dengue virus (DENV), we tested 36 ISGs that are commonly induced by IFN-alpha for antiviral activity against the two viruses. We discovered that five ISGs efficiently suppressed WNV and/or DENV infection when they were individually expressed in HEK293 cells. Mechanistic analyses revealed that two structurally related cell plasma membrane proteins, IFITM2 and IFITM3, disrupted early steps (entry and/or uncoating) of the viral infection. In contrast, three IFN-induced cellular enzymes, viperin, ISG20, and double-stranded-RNA-activated protein kinase, inhibited steps in viral proteins and/or RNA biosynthesis. Our results thus imply that the antiviral activity of IFN-alpha is collectively mediated by a panel of ISGs that disrupt multiple steps of the DENV and WNV life cycles.
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Virus del Dengue/inmunología , Interacciones Huésped-Patógeno , Interferón-alfa/inmunología , Proteínas de la Membrana/inmunología , Proteínas/inmunología , Proteínas de Unión al ARN/inmunología , Virus del Nilo Occidental/inmunología , Línea Celular , Exonucleasas/biosíntesis , Exonucleasas/inmunología , Exorribonucleasas , Regulación de la Expresión Génica , Humanos , Proteínas de la Membrana/biosíntesis , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH , Proteínas/metabolismo , Proteínas de Unión al ARN/biosíntesis , Internalización del Virus , Replicación Viral/inmunología , eIF-2 Quinasa/biosíntesis , eIF-2 Quinasa/inmunologíaRESUMEN
BACKGROUND: How to treat infantile hepatitis B virus (HBV) infection remains a controversial issue. The nucleoside analogue lamivudine (LAM) has been approved to treat children (2 to 17 years old) with chronic hepatitis B. Here, we aimed to investigate the benefit of LAM treatment in infantile hepatitis B. CASE SUMMARY: A 4-mo-old infant born to a hepatitis B surface antigen (HBsAg)-positive woman was found to be infected by HBV during a health checkup. Liver chemistry and HBV seromarker tests showed alanine aminotransferase of 106 U/L, HBsAg of 685.2 cut-off index, hepatitis B "e" antigen of 1454.0 cut-off index, and HBV DNA of > 1.0 × 109 IU/mL. LAM treatment (20 mg/d) was initiated, and after 19 mo, serum HBsAg was entirely cleared and hepatitis B surface antibody was present. The patient received LAM treatment for 2 years in total and has been followed for 3 years. During this period, serum hepatitis B surface antibody has been persistently positive, and serum HBV DNA was undetectable. CONCLUSION: Early treatment of infantile hepatitis B with LAM could be safe and effective.
RESUMEN
Interferon gamma-inducible protein 16 (IFI16) is a DNA sensor protein, which triggers interferon-beta (IFN-ß) production. However, the role of IFI16 in the innate immunity against hepatitis B virus (HBV) remains controversial. Peripheral blood mononuclear cells (PBMCs) and serum specimens were collected from 20 patients with chronic hepatitis B (CHB) receiving Peg-IFN-α2b therapy. IFI16 mRNA/protein of PBMCs and serum IFI16 at baseline and changes during Peg-IFN-α2b treatment were detected. The interaction between IFI16 and HBV DNA in the PBMCs was analyzed using chromatin immunoprecipitation assay. Leukemic T cell line CEM-C7 and HBV-replicating HepG2.2.15 cells were used to test the effects of interferon treatment and HBV replication on IFI16 expression. Compared with healthy controls, lower levels of IFI16 mRNA but more significant expression of IFI16 protein with heterogeneous degradation were detected in PBMCs of CHB patients. Early changes in IFI16 mRNA, but not IFNB mRNA of PBMCs or serum IFI16, were correlated to HBeAg seroconversion of Peg-IFN-α2b therapy. An interaction between IFI16 and HBV DNA was detected in the PBMCs. In the cultured HepG2.2.15 and CEM-C7 cells, interferons resulted in the translocalization of IFI16 from the cytoplasm to the nucleus and inhibited IFI16 degradation. IFI16 of PBMCs may play a role in sensing HBV infection, and early change in IFI16 mRNA of PBMCs is valuable to predict HBeAg seroconversion in Peg-IFN-α2b treatment. The influences on IFI16 degradation and subcellular location may present a molecular mechanism of antiviral activity of interferon.
Asunto(s)
Antivirales , Hepatitis B , Proteínas Nucleares/inmunología , Fosfoproteínas/inmunología , Antivirales/uso terapéutico , Células Cultivadas , Hepatitis B/tratamiento farmacológico , Hepatitis B/inmunología , Humanos , Interferón alfa-2/uso terapéutico , Interferón-alfa/uso terapéutico , Leucocitos Mononucleares , Polietilenglicoles/uso terapéutico , Proteínas Recombinantes/uso terapéuticoRESUMEN
Background: Pre-existing liver disease is a risk factor for the worse prognosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We aimed to evaluate whether chronic hepatitis B (CHB) and hepatocellular carcinoma (HCC) affect the expression of viral receptor angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2) in the liver. Methods: Twelve pairs of matched liver tissues of HCC and para-carcinoma were collected from the First Affiliated Hospital of Zhejiang University School of Medicine. And 20 liver biopsies from CHB patients were collected from Peking University People's Hospital. The expression of ACE2 and TMRPSS2 were detected using immunofluorescence staining, western blot, and RT-qPCR. The effects of hepatitis B virus (HBV) replication or interferon on ACE2 and TMPRSS2 expression were tested in hepatic cell lines. Results: The mRNA expression of TMPRSS2 in HCC tissues was six-fold higher than that of para-carcinoma tissues (Pâ=â0.002), whereas that of ACE2 was not statistically different between HCC and para-carcinoma tissues. Hepatocellular ACE2 expression was detected in 35% (7/20) of CHB patients and mostly distributed in the inflammatory areas. However, there was no difference in TMPRSS2 expression between areas with or without inflammation. IFN-α2b slightly induced ACE2 expression (2.4-fold, Pâ=â0.033) in HepG2 cells but not in Huh-7, QSG-7701, and L-02 cells. IFN-α2b did not affect TMPRSS2 expression in these cell lines. In addition, HBV replication did not alter ACE2 expression in HepAD38 cells. Conclusions: Although HBV replication does not directly affect the expression of ACE2 and TMPRSS2, intrahepatic inflammation and carcinogenesis may increase their expression in some patients, which, in turn, may facilitate SARS-CoV-2 infection in hepatocytes.