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da Silva H, Juniastuti, Amin M, Soares J, Soares M, Malik H, Ximenes A, Bela M, Fernandes B. Genotypes, subtypes, and genetic variability of hepatitis B virus from blood donors in Timor-Leste. Arch Virol 2025; 170:119. [PMID: 40310552 DOI: 10.1007/s00705-025-06305-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2024] [Accepted: 03/17/2025] [Indexed: 05/02/2025]
Abstract
Timor-Leste experiences high hepatitis B endemicity; however, information about hepatitis B virus (HBV) variants in Timor-Leste is still limited. In this study, we determined genotypes and subtypes and identified mutations in the surface (S), polymerase (P), basal core promoter (BCP), precore (PC), and core (C) genes of HBV isolates from blood donors in Timor-Leste. Sera were examined using serological tests and PCR sequencing. Out of 127 sera tested, 38 (30%) were positive for the hepatitis B S antigen (HBsAg). Thirty-eight sequences of the S and P genes, 22 sequences of the BCP and PC regions, and 23 sequences of C genes were determined and analyzed. The most common genotype/subtype was C/adrq+, followed by B/ayw1, B/adw2, and C/adw2. Several mutations in the S protein that are associated with vaccine escape were identified in samples of genotype C (I110L, S113T, T126I, T143S, Y161F) and B (K122R), some of which might have been from vaccinated individuals. None of the healthy carriers had taken anti-HBV drugs, but one was infected with a virus with a mutation in the P gene associated with anti-HBV drug resistance (Y141F). The mutations A1762T and G1764A in BCP were detected in 18.1-22.7% of the samples. In the PC region, the mutation C1858T was the most frequent, followed by G1896A and G1899A. In the C gene, 13 mutations (P5T, T67N, E77Q, P79Q/A, E83D, V91T, I97L/F, L116I, and P130I/P/T) associated with severe liver disease were identified. Viruses obtained from four healthy carriers who were later found to have died of hepatocellular carcinoma also showed those mutations. In conclusion, among blood donors in Timor-Leste, HBV genotype/subtype C/adrq+ and several mutations in the S and C genes were prevalent. Routine implementation of a national immunization program and monitoring of disease progression in healthy carriers should be considered.
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Affiliation(s)
- Hendriketa da Silva
- Postdoctoral Fellowship Program, Universitas Airlangga, Surabaya, Indonesia
- Postgraduation and Research Program, Faculty of Medicine and Health Sciences, Universidade Nacional Timor-Loro sae, Dili, Timor-Leste
| | - Juniastuti
- Department of Medical Microbiology, School of Medicine, Universitas Airlangga, Jl. Mayjen. Prof. Dr. Moestopo 47, Surabaya, East Java, 60131, Indonesia.
- Institute of Tropical Disease, Universitas Airlangga, Surabaya, Indonesia.
| | - Mochamad Amin
- Institute of Tropical Disease, Universitas Airlangga, Surabaya, Indonesia
| | | | - Miguel Soares
- Hospital Nacional Guido Valadares, Dili, Timor-Leste
| | - Hitler Malik
- Hospital Nacional Guido Valadares, Dili, Timor-Leste
| | | | - Maria Bela
- Hospital Nacional Guido Valadares, Dili, Timor-Leste
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Nolte FS. Molecular Microbiology. PRINCIPLES AND APPLICATIONS OF MOLECULAR DIAGNOSTICS 2018. [PMCID: PMC7150357 DOI: 10.1016/b978-0-12-816061-9.00005-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Background Nucleic acid (NA) amplification techniques are now commonly used to diagnose and manage patients with infectious diseases. The growth in the number of Food and Drug Administration–approved test kits and analyte-specific reagents has facilitated the use of this technology in clinical laboratories. Technological advances in NA amplification techniques, automation, NA sequencing, and multiplex analysis have reinvigorated the field and created new opportunities for growth. Simple, sample-in, answer-out molecular test systems are now widely available that can be deployed in a variety of laboratory and clinical settings. Molecular microbiology remains the leading area in molecular pathology in terms of both the numbers of tests performed and clinical relevance. NA-based tests have reduced the dependency of the clinical microbiology laboratory on more traditional antigen detection and culture methods and created new opportunities for the laboratory to impact patient care. Content This chapter reviews NA testing as it applies to specific pathogens or infectious disease syndromes, with a focus on those diseases for which NA testing is now considered the standard of care and highlights the unique challenges and opportunities that these tests present for clinical laboratories.
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Mansourian PG, Ghany MG, Thomas E. Spontaneous Mutations in the HBV Genome and their Clinical Implications. ACTA ACUST UNITED AC 2013. [DOI: 10.1007/s11901-013-0170-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Cho EY, Choi CS, Cho JH, Kim HC. Association between Hepatitis B Virus X Gene Mutations and Clinical Status in Patients with Chronic Hepatitis B Infection. Gut Liver 2011; 5:70-6. [PMID: 21461076 DOI: 10.5009/gnl.2011.5.1.70] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2010] [Accepted: 10/22/2010] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND/AIMS Few reports have described the association between mutations in the entire X gene of the hepatitis B virus (HBV) and the clinical status of HBV-infected patients. We studied the association between HBV X gene mutations and the disease status of patients infected with HBV genotype C. METHODS Mutations in the HBV X genes of 194 patients were determined by direct sequencing. The subject population consisted of patients with chronic hepatitis (n=60), liver cirrhosis (n=65), and hepatocellular carcinoma (HCC) (n=69). The sequencing results of these 3 groups were compared. RESULTS Each of the mutations G1386M, C1485T, C1653T, T1753V, A1762T, and G1764A was significantly associated with the patient's clinical status. The T1753V (p<0.001) and A1762T/G1764A (p<0.001) mutations were found more frequently in Hepatitis B e antigen (HBeAg)-negative than in HBeAg-positive patients. Specific X gene mutations (G1386M, C1653T, and A1762T/G1764A) were more prevalent in patients with liver cirrhosis and HCC than in chronic hepatitis patients (p<0.005 for all). In addition, the T1753V (p<0.001) and C1485T (p<0.001) mutations were significantly more prevalent in HCC patients than in chronic hepatitis patients. Only the prevalence of the T1753V mutation increased as the HBV infection progressed from liver cirrhosis to HCC (p=0.023). CONCLUSIONS Our findings show a difference in the pattern of X gene mutations that were associated with the clinical status of patients with chronic HBV infection.
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Affiliation(s)
- Eun Young Cho
- Department of Internal Medicine, Wonkwang University Hospital, Wonkwang University College of Medicine, Iksan, Korea
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Guan ZJ, Guo B, Huo YL, Guan ZP, Wei YH. Overview of expression of hepatitis B surface antigen in transgenic plants. Vaccine 2010; 28:7351-62. [PMID: 20850538 DOI: 10.1016/j.vaccine.2010.08.100] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2010] [Revised: 08/20/2010] [Accepted: 08/31/2010] [Indexed: 11/18/2022]
Abstract
Hepatitis B virus (HBV), a pathogen for chronic liver infection, afflicts more than 350 million people world-wide. The effective way to control the virus is to take HBV vaccine. Hepatitis B surface antigen (HBsAg) is an effective protective antigen suitable for vaccine development. At present, "edible" vaccine based on transgenic plants is one of the most promising directions in novel types of vaccines. HBsAg production from transgenic plants has been carried out, and the transgenic plant expression systems have developed from model plants (such as tobacco, potato and tomato) to other various plant platforms. Crude or purified extracts of transformed plants have been found to conduct immunological responses and clinical trials for hepatitis B, which gave the researches of plant-based HBsAg production a big boost. The aim of this review was to summarize the recent data about plant-based HBsAg development including molecular biology of HBsAg gene, selection of expression vector, the expression of HBsAg gene in plants, as well as corresponding immunological responses in animal models or human.
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Affiliation(s)
- Zheng-jun Guan
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education Northwest University, Xi'an 710069, China.
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Inoue J. Factors involved in the development of fulminant hepatitis B: Are the mutations of hepatitis B virus implicated? Hepatol Res 2009; 39:1053-5. [PMID: 19878349 DOI: 10.1111/j.1872-034x.2009.00609.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Jun Inoue
- Division of Gastroenterology, Tohoku University Graduate School of Medicine, Sendai, Japan
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Yuen LKW, Locarnini SA. Genetic variability of hepatitis B virus and response to antiviral treatments: searching for a bigger picture. J Hepatol 2009; 50:445-8. [PMID: 19152982 DOI: 10.1016/j.jhep.2008.12.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Yang HI, Yeh SH, Chen PJ, Iloeje UH, Jen CL, Su J, Wang LY, Lu SN, You SL, Chen DS, Liaw YF, Chen CJ. Associations between hepatitis B virus genotype and mutants and the risk of hepatocellular carcinoma. J Natl Cancer Inst 2008; 100:1134-43. [PMID: 18695135 PMCID: PMC2518166 DOI: 10.1093/jnci/djn243] [Citation(s) in RCA: 481] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Background The risk of hepatocellular carcinoma (HCC) increases with increasing level of hepatitis B virus (HBV) in serum (viral load). However, it is unclear whether genetic characteristics of HBV, including HBV genotype and specific genetic mutations, contribute to the risk of HCC. We examined the HCC risk associated with HBV genotypes and common variants in the precore and basal core promoter (BCP) regions. Methods From January 5, 1991, to December 21, 1992, baseline blood samples were collected from 2762 Taiwanese men and women who were seropositive for HBV surface antigen but had not been diagnosed with HCC; the samples were tested for HBV viral load by real-time polymerase chain reaction and genotyped by melting curve analysis. Participants who had a baseline serum HBV DNA level greater than 104 copies/mL (n = 1526) were tested for the precore G1896A and BCP A1762T/G1764A mutants by direct sequencing. Incident cases of HCC were ascertained through follow-up examinations and computerized linkage to the National Cancer Registry and death certification profiles. A Cox proportional hazards model was used to estimate the risk of HCC associated with HBV genotype and precore and BCP mutants after adjustment for other risk factors. All statistical tests were two-sided. Results A total of 153 HCC cases occurred during 33 847 person-years of follow-up. The HCC incidence rates per 100 000 person-years for participants infected with HBV genotype B or C were 305.6 (95% confidence interval [CI] = 236.9 to 388.1) and 785.8 (95% CI = 626.8 to 972.9), respectively. Among participants with a baseline HBV DNA level of at least 104 copies/mL, HCC incidence per 100 000 person-years was higher for those with the precore G1896 (wild-type) variant than for those with the G1896A variant (955.5 [95% CI = 749.0 to 1201.4] vs 269.4 [95% CI = 172.6 to 400.9]) and for those with the BCP A1762T/G1764A double mutant than for those with BCP A1762/G1764 (wild-type) variant (1149.2 [95% CI = 872.6 to 1485.6] vs 358.7 [95% CI = 255.1 to 490.4]). The multivariable-adjusted hazard ratio of developing HCC was 1.76 (95% CI = 1.19 to 2.61) for genotype C vs genotype B, 0.34 (95% CI = 0.21 to 0.57) for precore G1896A vs wild type, and 1.73 (95% CI = 1.13 to 2.67) for BCP A1762T/G1764A vs wild type. Risk was highest among participants infected with genotype C HBV and wild type for the precore 1896 variant and mutant for the BCP 1762/1764 variant (adjusted hazard ratio = 2.99, 95% CI = 1.57 to 5.70, P < .001). Conclusions HBV genotype C and specific alleles of BCP and precore were associated with risk of HCC. These associations were independent of serum HBV DNA level.
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Affiliation(s)
- Hwai-I Yang
- Genomics Research Center, Academia Sinica and Graduate Institute of Epidemiology, National Taiwan University, Taipei, Taiwan
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Abstract
Three hundred and fifty million people worldwide are estimated to be chronically infected with hepatitis B virus. 15%-40% of these subjects will develop cirrhosis, liver failure or hepatocellular carcinoma during their life. The treatment of chronic hepatitis B has improved dramatically over the last decade merits to the advent of nucleoside/nucleotide analogues and the use of pegylated interferons. Approved drugs for chronic hepatitis B treatment include: standard interferon-alpha 2b, pegylated interferon-alpha 2a, lamivudine, adefovir dipivoxil, and entecavir. Unfortunately, these agents are not effective in all patients and are associated with distinct side effects. Interferons have numerous side effects and nucleoside or nucleotide analogues, which are well tolerated, need to be used for prolonged periods, even indefinitely. However, prolonged treatment with nucleoside or nucleotide analogues is associated with a high rate of resistance. Telbivudine is a novel, orally administered nucleoside analogue for use in the treatment of chronic hepatitis B. In contrast to other nucleoside analogues, Telbivudine has not been associated with inhibition of mammalian DNA polymerase with mitochondrial toxicity. Telbivudine has demonstrated potent activity against hepatitis B with a significantly higher rate of response and superior viral suppression compared with lamivudine, the standard treatment. Telbivudine has been generally well tolerated, with a low adverse effect profile, and at its effective dose, no dose-limiting toxicity has been observed. Telbivudine is one of the most potent antiviral agents for chronic hepatitis B virus and was approved by the FDA in late 2006.
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Affiliation(s)
- Deepak N Amarapurkar
- Department of Gastroenterology and Hepatology, Bombay Hospital & Medical Research Centre, Mumbai 400025, India.
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Amarapurkar DN. Telbivudine: a new treatment for chronic hepatitis B. World J Gastroenterol 2007; 13:6150-5. [PMID: 18069753 PMCID: PMC4171223 DOI: 10.3748/wjg.v13.i46.6150] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2007] [Revised: 09/25/2007] [Accepted: 10/16/2007] [Indexed: 02/06/2023] Open
Abstract
Three hundred and fifty million people worldwide are estimated to be chronically infected with hepatitis B virus. 15%-40% of these subjects will develop cirrhosis, liver failure or hepatocellular carcinoma during their life. The treatment of chronic hepatitis B has improved dramatically over the last decade merits to the advent of nucleoside/nucleotide analogues and the use of pegylated interferons. Approved drugs for chronic hepatitis B treatment include: standard interferon-alpha 2b, pegylated interferon-alpha 2a, lamivudine, adefovir dipivoxil, and entecavir. Unfortunately, these agents are not effective in all patients and are associated with distinct side effects. Interferons have numerous side effects and nucleoside or nucleotide analogues, which are well tolerated, need to be used for prolonged periods, even indefinitely. However, prolonged treatment with nucleoside or nucleotide analogues is associated with a high rate of resistance. Telbivudine is a novel, orally administered nucleoside analogue for use in the treatment of chronic hepatitis B. In contrast to other nucleoside analogues, Telbivudine has not been associated with inhibition of mammalian DNA polymerase with mitochondrial toxicity. Telbivudine has demonstrated potent activity against hepatitis B with a significantly higher rate of response and superior viral suppression compared with lamivudine, the standard treatment. Telbivudine has been generally well tolerated, with a low adverse effect profile, and at its effective dose, no dose-limiting toxicity has been observed. Telbivudine is one of the most potent antiviral agents for chronic hepatitis B virus and was approved by the FDA in late 2006.
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Dougherty AM, Guo H, Westby G, Liu Y, Simsek E, Guo JT, Mehta A, Norton P, Gu B, Block T, Cuconati A. A substituted tetrahydro-tetrazolo-pyrimidine is a specific and novel inhibitor of hepatitis B virus surface antigen secretion. Antimicrob Agents Chemother 2007; 51:4427-37. [PMID: 17875990 PMCID: PMC2167973 DOI: 10.1128/aac.00541-07] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The high levels of hepatitis B virus (HBV) surface antigen (HBsAg)-bearing subviral particles in the serum of chronically infected individuals are thought to play a role in suppressing the HBV-specific immune response. Current therapeutics are not directed at reducing this viral antigenemia; thus, our group has focused on identifying inhibitors of HBsAg secretion. By using the HBV-expressing cell line HepG2.2.15, high-throughput screening of an 80,288-compound synthetic small-molecule library identified HBF-0259, an aromatically substituted tetrahydro-tetrazolo-(1, 5-a)-pyrimidine. Following resynthesis, HBF-0259 had a 50% effective concentration of approximately 1.5 microM in a secondary, HBV-expressing cell line, with a concentration that exhibited 50% cytotoxicity of >50 microM. The equilibrium concentration of HBF-0259 in aqueous solution at physiological pH was 15 to 16 microM; the selective index was thus >9. As intended by our screening paradigm, HBF-0259 is a selective, potent inhibitor of secretion of both subviral and DNA-containing viral particles, while the secretion of alpha-1-acid glycoprotein and alpha-1-antitrypsin was unaffected. The HBV e antigen, which is not a constituent of HBV particles, was also unaffected, suggesting that the secretion of particles bearing HBV structural glycoproteins is targeted directly. Inhibitory activity was also confirmed by transfection of HBsAg, indicating that the action of the compound is independent of those of other viral proteins. HBF-0259 had no effect on HBV DNA synthesis, demonstrating that inhibition is independent of viral genomic replication. Finally, HBF-0259 had little or no effect on the cell-to-cell spread of two unrelated viruses, suggesting that it is a specific inhibitor of secretion of HBsAg. Possible mechanisms of action and the implications for its development are discussed.
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Affiliation(s)
- Anne Marie Dougherty
- Institute for Hepatitis and Virus Research, Hepatitis B Foundation, 3805 Old Easton Road, Doylestown, PA 18902, USA
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12
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Rizzetto M, Zoulim F. Viral Hepatitis. TEXTBOOK OF HEPATOLOGY 2007:819-956. [DOI: 10.1002/9780470691861.ch9a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2025]
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Wang L, Tsai TH, Huang CF, Ho MS, Lin DB, Ho YC, Lin SS, Wei JCC, Chou MC, Yang CC. Utilizing self-prepared ELISA plates for a cross-population study of different anti-HBe IgG subclass profiles. J Med Virol 2007; 79:495-502. [PMID: 17385671 DOI: 10.1002/jmv.20852] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Fourteen serum samples obtained from hepatitis B virus (HBV) chronic carriers and patients recovered from hepatitis B infection were used with four sodium dodecyl sulfate-treated enzyme-linked immunosorbent assay (ELISA) plates available commercially, and one self-prepared HBcAg analog for evaluation of anti-HBe subclass pattern absorbance. The self-prepared plates had the best performance and were thus used for samples obtained from 104 (60 male and 44 female) HBV chronic carriers and 439 (247 male and 192 female) recovered individuals. Tests for aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were also carried out in 21 of the subjects (>25 IU/ml). Statistical comparison of these patients with elevated ALT/AST levels with other ALT/AST-normal chronic carriers revealed no significant differences in the anti-HBe OD, although the mean optical density (OD) of patients with elevated ALT/AST levels was higher. The results suggest that the anti-HBe IgG subclass profiles in the chronic carriers did not change with inflammation of the liver, and were independent of sex and age. In contrast to previous anti-HBc findings, the distribution pattern of anti-HBe subclasses in HBV chronic carriers was IgG1 > IgG4 > IgG3 while in the recovered individuals it was IgG1 > IgG3 > IgG4, for both males and females. Subclasses IgG1 and IgG2 were the most and least prevalent isotypes, respectively, in both study groups. The results of the study suggest that induction of IgG1 and/or IgG3 antibodies is important for effective virus neutralization, while IgG2 antibodies are of limited importance. Significantly higher OD values for anti-HBe IgG4 were observed when comparing samples from the chronic carriers and recovered individuals, which may reflect the effects of persistence. Further, in contrast to previous anti-HBs results, the concentrations of total IgG and IgG1 were higher in the samples from chronic carriers relative to those from recovered individuals.
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Affiliation(s)
- Lina Wang
- School of Medical Laboratory and Biotechnology, Chung Shan Medical University, Taichung, Taiwan
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Mao H, Wang H, Zhang D, Mao H, Zhao J, Shi J, Cui Z. Study of hepatitis B virus gene mutations with enzymatic colorimetry-based DNA microarray. Clin Biochem 2006; 39:67-73. [PMID: 16330012 DOI: 10.1016/j.clinbiochem.2005.10.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2005] [Revised: 07/17/2005] [Accepted: 10/17/2005] [Indexed: 11/21/2022]
Abstract
OBJECTIVES To establish a modified microarray method for detecting HBV gene mutations in the clinic. DESIGN AND METHODS Site-specific oligonucleotide probes were immobilized to microarray slides and hybridized to biotin-labeled HBV gene fragments amplified from two-step PCR. Hybridized targets were transferred to nitrocellulose membranes, followed by intensity measurement using BCIP/NBT colorimetry. RESULTS HBV genes from 99 Hepatitis B patients and 40 healthy blood donors were analyzed. Mutation frequencies of HBV pre-core/core and basic core promoter (BCP) regions were found to be significantly higher in the patient group (42%, 40% versus 2.5%, 5%, P < 0.01). Compared with a traditional fluorescence method, the colorimetry method exhibited the same level of sensitivity and reproducibility. CONCLUSIONS An enzymatic colorimetry-based DNA microarray assay was successfully established to monitor HBV mutations. Pre-core/core and BCP mutations of HBV genes could be major causes of HBV infection in HBeAg-negative patients and could also be relevant to chronicity and aggravation of hepatitis B.
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Affiliation(s)
- Hailei Mao
- Intensive Care Unit, Affiliated Hospital of Nantong University, China
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Chowdhury A, Santra A, Chakravorty R, Banerji A, Pal S, Dhali GK, Datta S, Banerji S, Manna B, Chowdhury SR, Bhattacharya SK, Mazumder DG. Community-based epidemiology of hepatitis B virus infection in West Bengal, India: prevalence of hepatitis B e antigen-negative infection and associated viral variants. J Gastroenterol Hepatol 2005; 20:1712-20. [PMID: 16246191 DOI: 10.1111/j.1440-1746.2005.04070.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND AIMS There is a paucity of population-based epidemiological information regarding hepatitis B virus (HBV) infection in India. The present study was planned to outline the magnitude and pattern of HBV infection, hepatitis B e antigen (HBeAg)-negative infection and the associated viral mutants in India. METHODS A community-based epidemiological study of HBV infection was carried out in West Bengal, India. Serological markers of infection and potential risk factors for HBV transmission were determined. Among the infected individuals, HBV-DNA, genotypes and mutations in the precore (PC) stop codon and basal core promoter (BCP) regions were determined by DNA sequencing and polymerase chain reaction (PCR) restriction fragment length polymorphism methods. RESULTS Of the 7653 people included in the study, 227 (2.97%) tested positive for hepatitis B surface antigen (HBsAg), of whom 204 (90%) were HBeAg-negative and hepatitis B e antibody (anti-HBe)-positive, and 78% had normal alanine aminotransferase (ALT) levels. HBV-DNA could be detected by PCR in only 32% of people. G1896A PC stop codon mutants were present in 12% of people, BCP mutants in 18% and the remainder (70%) of the HBeAg-negative infections were associated with wild type sequences in these regions. CONCLUSIONS This first general population-based epidemiological study of HBV infection from India suggests that HBV acquisition starts in early childhood and peaks in adulthood. Most infections in the community are e-negative and inactive. The point prevalence of PC stop codon and BCP mutants is low in this primarily inactive and asymptomatic HBV-infected population sample in eastern India.
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Affiliation(s)
- Abhijit Chowdhury
- Department of Gastroenterology, Institute of Post Graduate Medical Education and Research, Kolkata, India.
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Akuta N, Kumada H. Influence of hepatitis B virus genotypes on the response to antiviral therapies. J Antimicrob Chemother 2004; 55:139-42. [PMID: 15618285 DOI: 10.1093/jac/dkh533] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Hepatitis B virus (HBV) has been classified into eight genotypes (A-H) based on genome sequence divergence. Genotypes of HBV have distinct geographical distributions, and two genotypes account for most HBV worldwide. Hepatitis B e antigen expression lasts longer and liver disease is more severe with graver outcomes in carriers of genotype C than B in Asia. Accumulating lines of evidence indicate a better response to interferon and lamivudine in patients with chronic hepatitis B who are infected with genotype B rather than C. The therapeutic response may differ, however, in patients infected with HBV of the same genotype. For example, the response to lamivudine is poorer in patients infected with subtype Ba, which contains a recombination with genotype C, than in those with subtype Bj without such a recombination. Influence of genotypes on therapeutic response needs to be examined in patients infected with the other genotypes, particularly in those with genotype A or D infection.
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Affiliation(s)
- Norio Akuta
- Department of Gastroenterology, Toranomon Hospital, 2-2-2 Toranomon, Minato-ku, Tokyo, 105-0001, Japan.
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Affiliation(s)
- Hari S Conjeevaram
- Division of Gastroenterology, University of Michigan Medical Center, 3912 Taubman Center, Ann Arbor, MI 48109-0362, USA
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Chan TM, Fang GX, Tang CSO, Cheng IKP, Lai KN, Ho SKN. Preemptive lamivudine therapy based on HBV DNA level in HBsAg-positive kidney allograft recipients. Hepatology 2002; 36:1246-52. [PMID: 12395336 DOI: 10.1053/jhep.2002.36156] [Citation(s) in RCA: 127] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Hepatitis B surface antigen (HBsAg)-positive kidney transplant recipients have increased liver-related mortality. The impact of lamivudine treatment on patient survival, the optimal time to start treatment, and the feasibility of discontinuing treatment have not been determined. This study examined these issues with a novel management protocol. Serum hepatitis B virus (HBV) DNA levels were measured serially in HBsAg-positive kidney transplant recipients, and lamivudine was administered preemptively to patients with increasing HBV DNA levels with or without elevation of aminotransferase levels. Outcomes of patients who underwent transplantation before or after institution of this preemptive management strategy (in January 1996) were compared. Eleven de novo patients (91.7%) who underwent transplantation between 1996 and 2000 and 15 existing patients (39.5%) who underwent transplantation between 1983 and 1995 received preemptive lamivudine therapy for 32.6 +/- 13.3 months. The treatment criteria were met by de novo patients at 8.4 +/- 6.2 months (range, 1-18 months) after transplantation. Suppression of HBV DNA and normalization of aminotransferase levels were achieved in all treated patients, and 21.4% had hepatitis B e antigen (HBeAg) seroconversion. The survival of preemptively managed de novo transplant patients was similar to that of HBsAg-negative controls, whereas HBsAg-positive patients who underwent transplantation before January 1996 had inferior survival (relative risk of death, 9.7 [P <.001]; relative risk of liver-related mortality, 68.0 [P <.0001]). Eleven patients (40.7%) developed lamivudine resistance. Discontinuation of lamivudine was attempted in 12 low-risk patients after stabilization and was successful in 5 (41.7%). In conclusion, preemptive lamivudine therapy based on serial HBV DNA levels and clinical monitoring improved the survival of HBsAg-positive renal allograft recipients. Treatment can be discontinued safely in selected patients after stabilization to minimize the selection of drug-resistant HBV mutants.
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Affiliation(s)
- Tak Mao Chan
- Nephrology Division, Department of Medicine, Queen Mary Hospital, University of Hong Kong, Hong Kong.
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19
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Kato H, Orito E, Gish RG, Sugauchi F, Suzuki S, Ueda R, Miyakawa Y, Mizokami M. Characteristics of hepatitis B virus isolates of genotype G and their phylogenetic differences from the other six genotypes (A through F). J Virol 2002; 76:6131-7. [PMID: 12021346 PMCID: PMC136184 DOI: 10.1128/jvi.76.12.6131-6137.2002] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Eight hepatitis B virus (HBV) isolates of genotype G were recovered from patients and sequenced over the entire genome. Six of them had a genomic length of 3,248 bp and two had genomic lengths of 3,239 bp (USG15) and 3,113 bp (USG18) due to deletions. The 10 HBV/G isolates, including the 8 sequenced isolates as well as the original isolate (AF160501) and another isolate (B1-89), had a close sequence homology of 99.3 to 99.8% among themselves (excluding USG18 with a long deletion) but of <88.7% to any of the 68 HBV isolates of the other six genotypes with the full-length sequence known. The eight HBV/G isolates possessed an insertion of 36 bp in the core gene and two stop codons in the precore region, as did the AF160501 and B1-89 isolates. The 10 HBV/G isolates clustered on a branch separate from those bearing the other six genotypes (A through F [A-F]) in the phylogenetic tree constructed from full-length sequences of 78 HBV isolates as well as in those constructed from the core, polymerase, X, and envelope genes. Despite two stop codons in the precore region that prohibited the translation of the HBV e antigen (HBeAg), all of the eight patients with HBV/G infection possessed the HBeAg in serum. By restriction fragment length polymorphism of the surface gene, all of the eight patients were found to be coinfected with HBV of genotype A (HBV/A), which would be responsible for the expression of HBeAg in them. It is worthy of examination to determine how coinfection occurs and whether HBV/G needs HBV/A for replication.
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Affiliation(s)
- Hideaki Kato
- Department of Internal Medicine and Molecular Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
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20
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Affiliation(s)
- A S Lok
- Division of Gastroenterology, University of Michigan, Ann Arbor, Michigan 48109-0362, USA.
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21
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Abstract
The core promoter (CP) of hepatitis B virus (HBV) plays a central role in HBV replication and morphogenesis, directing the transcription of both species of 3.5 kb mRNA: pregenomic (pg) RNA and precore (pre-C) mRNA. The CP overlaps the 3' end of the X open-reading frame (ORF) and the 5' end of the pre-C/C ORF. The major functional elements of the CP are the upper regulatory region (URR) and the basic core promoter (BCP). The BCP is sufficient for accurate initiation of both pre-C mRNA and pgRNA transcription. It contains four AT-rich regions and the initiators for pre-C mRNA and pgRNA transcription. The upstream regulatory region consists of the negative regulatory element and the core upstream regulatory sequence. Co-operative interaction of various liver-enriched and ubiquitous transcription factors is necessary for liver-specific expression from the CP. These factors bind to the CP. Sequence conservation within the CP is crucial for maintaining active viral replication, and variation may contribute to the persistence of HBV within the host, leading to chronic infection and, ultimately, hepatocarcinogenesis. The most frequently described mutations within this region are an A to T transversion at position 1762 together with a G to A transition at position 1764. This double mutant is accompanied by a reduced level of hepatitis B e antigen (HBeAg) expression. Deletions, insertions and duplications occur within the CP.
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Affiliation(s)
- A Kramvis
- Medical Research Council/CANSA/University Molecular Hepatology Research Unit, Department of Medicine, University of the Witwatersrand, Johannesburg, South Africa
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22
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Abstract
UNLABELLED Lamivudine is a deoxycytidine analogue that is active against hepatitis B virus (HBV). In patients with chronic hepatitis B, lamivudine profoundly suppresses HBV replication. Clinically significant improvements in liver histology and biochemical parameters were obtained with lamivudine in double-blind, randomised, trials in hepatitis B e antigen (HBeAg)-positive patients with chronic hepatitis B and compensated liver disease. After 52 weeks of treatment, relative to placebo (< or = 25%), significantly more Chinese (56%) or Western patients (52%) treated with lamivudine 100 mg/day had reductions of > or = 2 or more points in Knodell necro-inflammatory scores. Moreover, significantly fewer lamivudine 100 mg/day than placebo recipients had progressive fibrosis in liver biopsies (< or = 5 vs > or = 15%) and fewer lamivudine- than placebo-treated patients progressed to cirrhosis (1.8 vs 7.1%). More lamivudine 100 mg/day than placebo recipients acquired antibodies to HBeAg after 52 weeks (16 vs 4% in Chinese patients and 17 vs 6% in Western patients). ALT levels normalised in significantly more lamivudine than placebo recipients enrolled in these trials. In HBeAg-negative, HBV DNA positive patients with compensated liver disease enrolled in a double-blind, randomised study, HBV DNA levels were suppressed to below the limit of detection (< 2.5 pg/ml) and ALT levels normalised in 63% and 6% of patients treated with lamivudine 100 mg/day or placebo for 24 weeks. Clinically significant improvements in liver histology were obtained in 60% of patients treated with lamivudine for 52 weeks in this study. Lamivudine 100 mg/day for 52 weeks produced similar or significantly greater improvements in liver histology and ALT levels than 24 weeks' treatment with lamivudine plus interferon-alpha. In liver transplant candidates with chronic hepatitis B and end-stage liver disease, lamivudine 100 mg/day alone, or in combination with hepatitis B immune globulin, generally suppressed HBV replication and appeared to protect the grafted liver from reinfection. Lamivudine 100 mg/day suppressed viral replication and improved liver histology in liver transplant recipients with recurrent or de novo chronic hepatitis B. Lamivudine 300 or 600 mg/day reduced HBV replication in HIV-positive patients. The incidence of adverse events in patients with chronic hepatitis B and compensated liver disease treated with lamivudine 100 mg/day or placebo for 52 to 68 weeks was similar. 3.1- to 10-fold increases in ALT over baseline occurred in 13% of patients during treatment with lamivudine 100 mg/day or placebo for 52 weeks. Post-treatment ALT elevations were more common in lamivudine than placebo recipients; however, these generally resolved spontaneously; < or = 1.5% of lamivudine- or placebo-treated patients experienced hepatic decompensation. CONCLUSION Lamivudine inhibits HBV replication, reduces hepatic necro-inflammatory activity and the progression of fibrosis in patients with chronic hepatitis B, ongoing viral replication and compensated liver disease including HBeAg-negative patients. The drug also suppresses viral replication in liver transplant recipients and HIV-positive patients. Thus, lamivudine is potentially useful in a wide range of patients with chronic hepatitis B and ongoing viral replication.
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Affiliation(s)
- B Jarvis
- Adis International Limited, Auckland, New Zealand.
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23
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Baptista M, Kramvis A, Kew MC. High prevalence of 1762(T) 1764(A) mutations in the basic core promoter of hepatitis B virus isolated from black Africans with hepatocellular carcinoma compared with asymptomatic carriers. Hepatology 1999; 29:946-53. [PMID: 10051502 DOI: 10.1002/hep.510290336] [Citation(s) in RCA: 195] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The purpose of this study was to identify mutations in the basic core promoter and enhancer II region of the hepatitis B virus (HBV) that might cause the HBV e antigen (HBeAg)-negative phenotype and contribute to hepatocarcinogenesis in black African carriers of the virus. The basic core promoter/enhancer II overlaps with the X gene. HBV DNA from serum of 47 asymptomatic carriers and 50 patients with hepatocellular carcinoma and from 28 tumor and 10 nontumor liver tissues was amplified and sequenced directly. That part of the enhancer II region not overlapping the basic core promoter was completely conserved in all samples. Missense mutations at nucleotides 1809 and 1812 in the basic core promoter were found in 80% of all sequences and may represent wild-type sequence in Southern African isolates. Nucleotide and amino acid divergences were higher in the basic core promoter of hepatocellular carcinoma patients when compared with asymptomatic carriers (P <.0001). This applied particularly to the paired 1762 adenine to thymine (1762(T)) and 1764 guanine to adenine (1764(A)) missense mutations, the prevalence of which was 66% in patients with hepatocellular carcinoma compared with 11% in asymptomatic carriers (P <.0001). There was no association between the presence of 1762(T) 1764(A) and HBeAg negativity, although these mutations suppressed HBeAg titers in HBeAg-positive patients. Suppression of HBeAg expression as well as alteration of the amino acid sequence of the X protein may play a role in hepatocarcinogenesis.
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Affiliation(s)
- M Baptista
- Medical Research Council/CANSA/University Molecular Hepatology Research Unit, Department of Medicine, University of the Witwatersrand, Johannesburg, South Africa
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24
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Abstract
The hepatitis B virus (HBV) and other members of the hepadnaviridae replicate by reverse transcription of an RNA intermediate, pregenomic RNA (pgRNA). pgRNA is also translated into core protein and polymerase (reverse transcriptase) protein. Before being reverse transcribed, pgRNA is sequestrated from the cytoplasm by being packaged, together with polymerase, into subviral particles composed of core protein. For pgRNA to be encapsidated, its 5' end is folded into a stem-loop structure, known as the encapsidation signal or epsilon (epsilon). This stable bipartite stem-loop structure contains a bulge and an apical loop. Besides encapsidation, epsilon is involved in the activation of polymerase, in template restriction and in the initiation of DNA synthesis by reverse transcription. HBV DNA encoding epsilon forms part of the template that is translated into the precore/core fusion protein that is in turn post-translationally modified to produce hepatitis B e antigen (HBeAg). The DNA encoding epsilon may be recombinogenic. Mutations within epsilon can affect its function and sequence conservation within epsilon in natural isolates is therefore high. epsilon could provide a practical target for antiviral therapy.
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Affiliation(s)
- A Kramvis
- Department of Medicine, University of the Witwatersrand, Johannesburg, South Africa
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25
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Teles SA, Martins RM, Silva SA, Gomes DM, Cardoso DD, Vanderborght BO, Yoshidà CF. Hepatitis B virus infection profile in central Brazilian hemodialysis population. Rev Inst Med Trop Sao Paulo 1998; 40:281-6. [PMID: 10030071 DOI: 10.1590/s0036-46651998000500003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Hepatitis B has proved to be a major health hazard in hemodialysis patients. In order to investigate the hepatitis B virus (HBV) infection profile in the hemodialysis population of Goiânia city--Central Brazil, all dialysis patients (N = 282) were studied. The prevalence of any HBV marker (HBsAg, anti-HBs, and anti-HBc) was 56.7% (95% CI: 51.1-62.7), ranging from 33.3% to 77.7% depending on dialysis unit. HBV-DNA was detected in 67.6% and 88.2% of the HBsAg-positive serum samples, in 91.3% and 100% of the HBsAg/HBeAg-positive samples, and in 18.2% and 63.6% of the HBsAg/anti-HBe-reactive sera by hybridization and PCR, respectively. The length of time on hemodialysis was significantly associated with HBV seropositivity. Only 10% of the patients reported received hepatitis B vaccination. The findings of a high HBV infection prevalence in this population and the increased risk for HBV infection on long-term hemodialysis suggest the environmental transmission, emphasizing the urgent need to evaluate strategies of control and prevention followed in these units.
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Affiliation(s)
- S A Teles
- Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Brasil
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26
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Affiliation(s)
- F Torre
- Institute of Hepatology, University College London, London, UK
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27
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Sommer G, Günther S, Sterneck M, Otto S, Will H. A new class of defective hepatitis B virus genomes with an internal poly(dA) sequence. Virology 1997; 239:402-12. [PMID: 9434730 DOI: 10.1006/viro.1997.8898] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Sequence heterogeneity of hepatitis B virus (HBV) is increasingly recognized to play a role in virus-host interaction. We have used a recently established method for HBV full-length genome amplification to search for novel types of HBV variants and to investigate further the sequence heterogeneity of HBV genome populations. Using this method, a substantial fraction of HBV genomes much shorter than wildtype size was found in some sera and liver biopsies from infected patients. Cloning and sequencing of a number of these HBV genomes as well as hybridization studies revealed a new minor class of HBV genomes with an internal poly(dA) sequence approximately 60 to more than 100 nucleotides long in 4 of 10 patients. The 5'-ends of the internal poly(dA) sequences are located at positions corresponding to the authentic processing/polyadenylation sites of the RNA pregenome, whereas the positions of the 3'-ends are variable due to different sizes of adjacent deletions. These data suggest that the poly(A) tail of the pregenomic RNA is occasionally reverse transcribed by the HBV P-protein and during this process a deletion seems to be introduced into the DNA minus strand. We propose a mechanism by which this could be accomplished during DNA minus strand synthesis.
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Affiliation(s)
- G Sommer
- Heinrich-Pette-Institut für experimentalle Virologie und immunologie an, Universität Hamburg, Germany
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28
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Usuda S, Okamoto H, Ohnuma H, Tanaka T, Machida A, Miyakawa Y, Mayumi M. A monoclonal antibody against a hepatitis B e antigen epitope borne by six amino acids encoded by the precore region. J Virol Methods 1997; 68:207-15. [PMID: 9389411 DOI: 10.1016/s0166-0934(97)00125-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Hepatitis B e antigen (HBeAg) polypeptide in the circulation (p17e) is composed of ten amino acids (aa) coded for by the precore region and 149 aa by the core gene of hepatitis B virus. A monoclonal antibody (Y0583A) was raised against the N-terminal ten amino acids (SKLCLGWLWG) encoded by the precore region. The binding of Y0583A with a panel of 203 decapeptides on multipins, which covered the precursor of HBeAg polypeptide made of 212 aa shifting by one aa, recognized an epitope sequenced LGWLWG representing the C-terminal six aa coded for by the precore region. This HBeAg epitope was not readily accessible on HBeAg in serum, but it became exposed and bound with Y0583A by treatment with 0.2 N NaOH. Using Y0583A, an enzyme-linked immunosorbent assay was developed for specific determination of HBeAg. The test sample was incubated with the monoclonal antibody to an HBeAg determinant encoded by the core gene (904) that had been immobilized on a solid support. Captured HBeAg was treated with 0.2 N NaOH, neutralized and released into the fluid phase. The reactant was then tested for a sandwich between monoclonal antibody (C33) to the C-terminus of the HBeAg polypeptide immobilized on a solid support and Y0583A labeled with horseradish peroxidase.
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Affiliation(s)
- S Usuda
- Immunology Division, Jichi Medical School, Tochigi-Ken, Japan
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