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  1. Hepatitis B vaccine
    Wilkinson IE
    Med J Aust, 1992 May 18;156(10):741.
    PMID: 1535682
    Matched MeSH terms: Hepatitis B virus/immunology*
  2. Antigenicity and immunogenicity of the immunodominant region of hepatitis B surface antigen displayed on bacteriophage T7
    Tan GH, Yusoff K, Seow HF, Tan WS
    J Med Virol, 2005 Dec;77(4):475-80.
    PMID: 16254965
    The immunodominant region of hepatitis B virus (HBV) located in the viral small surface antigen (S-HBsAg) elicits virus-neutralizing and protective antibodies. In order to develop an easy and inexpensive method to produce this region without the need for extensive purification, amino acid residues 111-156 of S-HBsAg were fused to the C-terminal end of the 10B capsid protein of T7 phage. Western blotting and ELISA confirmed the expression of the recombinant protein on the surface of the phage particles. The recombinant phage exhibited the antigenic and immunogenic characteristics of HBsAg, illustrating its potential as an immunological reagent and vaccine.
    Matched MeSH terms: Hepatitis B virus/immunology
  3. HBV and liver cancer
    Leung N
    Med J Malaysia, 2005 Jul;60 Suppl B:63-6.
    PMID: 16108176
    The association of hepatitis B virus (HBV) infection and liver cancer is well documented in epidemiological study. Patients with chronic hepatitis B have increased risk of hepatocelluar carcinoma (HCC), in particular those with active liver disease and cirrhosis. The incidence of HCC increases with age and is more common among male patients. The introduction of universal HBV vaccination program for the newborn in endemic regions has started to show beneficial impact. Taiwan introduced this program two decades ago and the incidence of liver cancer among infants and young children have declined significantly. The carcinogenic events leading to HCC are under intense research. A number of hypotheses have been proposed. HBV is not directly hepatotoxic but its interaction with the host immune system creates opportunity for HBV DNA integration into the host genome. One of the main foci of research is the HBX-encoded X protein. Its integration and protein expression impose alteration in cell proliferation cycle and apoptosis process. Many other factors may be involved including viral-induced alterations in p53 and telemerase, HBV genotypes, co-infection with HCV or delta agents, patient's lifestyle such as smoking, alcohol excesses, and genetic factors of the host patient. The processes of necroinflammation, cell proliferation and fibrosis facilitate the initial carcinogenic development. HCC surveillance with tumor markers such as alpha-foetal protein, decarboxylated prothrombin, in conjunction with imaging techniques has identified early small HCC that is amenable to curative therapy. Viral load has been correlated with increase risk of HCC. The available anti-viral agents have demonstrated clinical benefit among those with maintained and sustained response. Interferon and lamivudine therapy have demonstrated reduction of HCC among responders. However, they only constitute a minority proportion of treated patients. The mainstay of prevention should lie in prevention of HBV infection and early effective therapy of chronic hepatitis B infection.
    Matched MeSH terms: Hepatitis B virus/immunology
  4. Serum hepatitis B virus DNA: relationship with the e-antigen and anti-e status in chronic carriers
    Yap SF, Wong NW, Goh KL
    Malays J Pathol, 1994 Jun;16(1):57-62.
    PMID: 16329577
    The relationship between serum Hepatitis B virus DNA (HBV-DNA) and the Hepatitis B e-antigen/ anti-Hepatitis Be (HBeAg/anti-HBe) serological status in Malaysians was studied. 212 cases of asymptomatic HBV carriers were recruited for this study. 92 cases were positive for the HBeAg at the point of recruitment. 85 (92.4%) of these patients tested positive for HBV-DNA, of whom 55 (64.7%) had levels over 100pg/ml of serum. Three of the remaining 7 HBeAg positive cases who were negative for HBV-DNA subsequently seroconverted. The other 4 cases remained negative for HBV-DNA for periods of 6-12 months. Out of 113 cases who were anti-HBe positive, 12 (10.6%) gave a positive HBV-DNA result. 2 of these 12 patients were recent seroconverters; the remaining cases had transiently increased viral replicative activity which later subsided. 7 out of the 212 carriers were in the e-window period; all 7 tested negative for HBV-DNA. Our data confirm a high frequency of HBV-DNA in HBeAg positive carriers and a negative correlation between HBV-DNA and anti-HBe. An atypical profile of anti-HBe associated with HBV-DNA was observed in 10.6% of the carriers. An inverse relationship between serum HBV-DNA levels and age was also observed.
    Matched MeSH terms: Hepatitis B virus/immunology
  5. Chronic hepatitis B infection in Malaysians
    Yap SF
    Malays J Pathol, 1994 Jun;16(1):3-6.
    PMID: 16329567
    Chronic hepatitis B virus (HBV) infection constitutes a major public health problem particularly in developing countries in East Asia, South-East Asia, the Pacific Basin and Africa. In Malaysia, a developing nation in the South East Asian region, the chronic HBV carrier rate varies between < 1% to about 10% depending on the ethnic group studied. The highest frequency is seen among the Chinese, followed by the Malays and lastly the Indians, with a male preponderance of between 2 : 1 and 3 : 1. Exposure to the virus among the adult population is estimated to be about 15%, 26% and 36% among the Indians, Malays and Chinese respectively. Serological study of adult chronic HBV carriers showed a frequency of HBe antigenemia of about 35%, with a significant decreasing trend with age. HBV DNA status generally correlated with the HBe status. An atypical profile of anti-HBe associated with serum HBV DNA is found in some carriers; in most instances, this is related to seroconversion from HBe antigenemia to anti-HBe. Chronic complications of HBV infection include the development of hepatocellular carcinoma (HCC), the occurrence of which closely parallel that of HBsAg carrier rate. In Malaysia, HCC is the third most common malignant neoplasm and among the 10 leading causes of death. About 80% of our HCC cases are HBV associated. All 3 ethnic groups are afflicted, the highest frequency being among the Chinese. Males show a disproportionate risk with an odds ratio of 3.93 (p < 0.0001).
    Matched MeSH terms: Hepatitis B virus/immunology
  6. Hepatitis B virus markers in prostitutes in Singapore
    Goh CL, Kamarudin A, Chan SH, Rajan VS
    Genitourin Med, 1985 Apr;61(2):127-9.
    PMID: 3980022
    The prevalence of hepatitis B virus markers in 121 men and 239 women prostitutes was studied. Of 33 (9.7%) with hepatitis B surface antigen (HBsAg), nine (27.3%) also had hepatitis Be antigen, which was more prevalent in men than women. Antibodies to HBsAg (anti-HBs) and to hepatitis B core antigen (anti-HBc) were found in about 71% of men and women prostitutes. Hepatitis B virus markers were more prevalent in men than in women prostitutes. Compared with other people, prostitutes had a significantly greater prevalence of hepatitis B virus markers. This study strongly suggested the importance of sexual transmission of infection with hepatitis B virus in a country where infection is endemic.
    Matched MeSH terms: Hepatitis B virus/immunology*
  7. Fulltext Expression of Human Cytokine Genes Associated with Chronic Hepatitis B Disease Progression
    Hudu SA, Niazlin MT, Nordin SA, Saeed MI, Tan SS, Sekawi Z
    Iran J Immunol, 2017 Dec;14(4):281-292.
    PMID: 29276181 DOI: IJIv14i4A3
    BACKGROUND: Hepatitis viruses are non-cytopathic viruses that lead to the infection and pathogenesis of liver diseases as a result of immunologically mediated events.

    OBJECTIVE: To investigate the expression of human inflammatory cytokines in chronic hepatitis B patients according to the severity of the infection.

    METHODS: We recruited a total of 120 patients, 40 of whom from cirrhotic, 40 non-cirrhotic, and 40 acute flare chronic hepatitis B and 40 healthy controls. For all groups total cellular RNA was extracted from whole blood samples, genomic DNA was eliminated, and cDNA was synthesized using the RT2 first strand kit, as instructed by the manufacturer. The real-time profiler PCR array was performed on a master cycler ep realplex and the data were analyzed using an online data analysis software.

    RESULTS: Non-cirrhotic chronic hepatitis B patients were found to significantly upregulate interleukin 10 receptors that regulate the balance between T helpers 1 and 2. On the other hand, patients with cirrhosis were found to have significant upregulated interleukin 3 gene expression.

    CONCLUSION: Our finding suggests that upregulation of anti-inflammatory and downregulation of pro-inflammatory cytokines may play a role in the progression of non-cirrhotic chronic hepatitis B patients to cirrhotic and acute flare. However, a multi-center study with a larger sample size is needed to confirm our findings.

    Matched MeSH terms: Hepatitis B virus/immunology*
  8. Fulltext Weighted analysis of prevalence and risk factors of hepatitis B infection among antenatal mothers in Ipoh
    Shamsuddin K, Marmuji LZ
    Singapore Med J, 2010 Oct;51(10):800-5.
    PMID: 21103816
    Several strategies have been developed to reduce hepatitis B infections. These include antenatal screening, universal immunisation of newborns and immunoglobulin therapy for babies who are at risk. Antenatal screening for hepatitis B is not routinely performed, but all newborns in Malaysia are immunised against hepatitis B. We assessed the prevalence of hepatitis B and the factors associated with it among antenatal mothers in Ipoh. This information is useful in decision-making for future hepatitis B screening programmes for antenatal mothers, allowing for immunoglobulin therapies for newborns if their mother's hepatitis B virus (HBV) status is known.
    Matched MeSH terms: Hepatitis B virus/immunology
  9. Bio-nanogate manipulation on electrode surface as an electrochemical immunosensing strategy for detecting anti-hepatitis B surface antigen
    Syamila N, Syahir A, Sulaiman Y, Ikeno S, Tan WS, Ahmad H, et al.
    Bioelectrochemistry, 2022 Feb;143:107952.
    PMID: 34600402 DOI: 10.1016/j.bioelechem.2021.107952
    The diagnosis of hepatitis B virus (HBV) and monitoring of the vaccination efficiency against HBV require real-time analysis. The presence of antibody against hepatitis B virus surface antigen (anti-HBsAg) as a result of HBV infection and/or immunization may indicate individual immune status towards HBV. This study investigated the ability of a bio-nanogate-based displacement immunosensing strategy in detecting anti-HBsAg antibody, via nonspecific-binding between polyamidoamine dendrimers encapsulated gold nanoparticles (PAMAM-Au) and the 'antigenic determinant' region (aD) of HBsAg. For this purpose, maltose binding protein harbouring the aD region (MBP-aD) was synthesized as a bioreceptor and immobilized on the screen-printed carbon electrode (SPCE). Following that, PAMAM-Au was deposited on MBP-aD, forming the 'gate' and was used as a monitoring agent. Under optimal conditions, the high specificity of anti-HBsAg antibody towards MBP-aD displaced PAMAM-Au causing the decrement of anodic peak in differential pulse voltammetry (DPV) analysis. The signal changes were proportionally related to the concentration of anti-HBsAg antibody, in a range of 1 - 1000 mIU/mL with a limit of detection (LOD) of 2.5 mIU/mL. The results also showed high specificity and selectivity of the immunosensor platform in detecting anti-HBsAg antibody both in spiked buffer and human serum samples.
    Matched MeSH terms: Hepatitis B virus/immunology
  10. Hepatitis B: review of development from the discovery of the "Australia Antigen" to end of the twentieth Century
    Yap SF
    Malays J Pathol, 2004 Jun;26(1):1-12.
    PMID: 16190102
    "Parenteral" or "serum" hepatitis is known to have afflicted man for centuries. However, it was not until the mid-1960s that the causative agent of this infection, the hepatitis B virus, was discovered. Since then, the biology and the replication strategy of the virus, and the clinical features and the epidemiology of the hepatitis B infection have been determined. Knowledge about the virus and the infection it causes led to the development of firstly, a plasma-derived vaccine and later a recombinant vaccine for the prevention of the infection. Integration of the hepatitis B vaccine into newborn vaccination programmes on a worldwide basis represents a major step in the effort to eliminate this infectious disease and its complications. Laboratory tests are available for the diagnosis and monitoring of the disease. Therapies have been developed to halt the progress of the chronic infection in affected individuals. While these developments have resulted in a decrease of the frequency of infection in many countries, particularly those that have implemented universal immunization of newborns, the chronic infection remains a significant global problem. Worldwide, over 300 million individuals are infected and each year, an estimated 1 million persons die from chronic complications of the disease including hepatocellular carcinoma and hepatic failure. The therapies currently available result in elimination of the virus in only a relatively small proportion of subjects and carry with it serious side effects. Geopolitical, economic and other factors hinder the vision of elimination of the infection through immunization programmes. Nevertheless, work continues to clarify further the underlying pathological mechanism of the infection, the host and viral factors that promote elimination or persistence of the virus in the human host. It is hoped that such investigations will reveal viral targets for the design of newer and potentially more effective drugs to treat the infection.
    Matched MeSH terms: Hepatitis B virus/immunology
  11. Interpretation and application of virological testing including resistance in chronic hepatitis B
    Locarnini S
    Med J Malaysia, 2005 Jul;60 Suppl B:41-51.
    PMID: 16108173
    Matched MeSH terms: Hepatitis B virus/immunology*
  12. Fulltext Naturally occurring hepatitis B virus surface antigen mutant variants in Malaysian blood donors and vaccinees
    Hudu SA, Harmal NS, Saeed MI, Alshrari AS, Malik YA, Niazlin MT, et al.
    Eur J Clin Microbiol Infect Dis, 2015 Jul;34(7):1349-59.
    PMID: 25792010 DOI: 10.1007/s10096-015-2358-1
    Hepatitis B virus surface mutants are of enormous importance because they are capable of escaping detection by serology and can infect both vaccinated and unvaccinated populations, thus putting the whole population at risk. This study aimed to detect and characterise hepatitis B-escaped mutants among blood donors and vaccinees. One thousand serum samples were collected for this study from blood donors and vaccinees. Hepatitis B surface antigen, antibodies and core antibodies were tested using a commercial enzyme-linked immunosorbent assay (ELISA) kit. DNA detection was performed via nested polymerase chain reaction (PCR), and the S gene was sequenced and analysed using bioinformatics. Of the 1,000 samples that were screened, 5.5% (55/1,000) were found to be HBsAg-negative and anti-HBc- and HBV DNA-positive. All 55 isolates were found to belong to genotype B. Several mutations were found across all the sequences from synonymous and non-synonymous mutations, with the most nucleotide mutations occurring at position 342, where adenine was replaced by guanine, and cytosine at position 46 was replaced by adenine in 96.4% and 98% of the isolates, respectively. Mutation at position 16 of the amino acid sequence was found to be common to all the Malaysian isolates, with 85.7% of the mutations occurring outside the major hydrophilic region. This study revealed a prevalence of 5.5% for hepatitis B-escaped mutations among blood donors and vaccinated undergraduates, with the most common mutation being found at position 16, where glutamine was substituted with lysine.
    Matched MeSH terms: Hepatitis B virus/immunology
  13. Fulltext Chimeric Virus-Like Particles of Prawn Nodavirus Displaying Hepatitis B Virus Immunodominant Region: Biophysical Properties and Cytokine Response
    Ninyio NN, Ho KL, Yong CY, Chee HY, Hamid M, Ong HK, et al.
    Int J Mol Sci, 2021 Feb 15;22(4).
    PMID: 33672018 DOI: 10.3390/ijms22041922
    Hepatitis B is a major global health challenge. In the absence of an effective treatment for the disease, hepatitis B vaccines provide protection against the viral infection. However, some individuals do not have positive immune responses after being vaccinated with the hepatitis B vaccines available in the market. Thus, it is important to develop a more protective vaccine. Previously, we showed that hepatitis B virus (HBV) 'a' determinant (aD) displayed on the prawn nodavirus capsid (Nc) and expressed in Spodoptera frugiperda (Sf9) cells (namely, Nc-aD-Sf9) self-assembled into virus-like particles (VLPs). Immunisation of BALB/c mice with the Nc-aD-Sf9 VLPs showed significant induction of humoral, cellular and memory B-cell immunity. In the present study, the biophysical properties of the Nc-aD-Sf9 VLPs were studied using dynamic light scattering (DLS) and circular dichroism (CD) spectroscopy. Enzyme-linked immunosorbent assay (ELISA) was used to determine the antigenicity of the Nc-aD-Sf9 VLPs, and multiplex ELISA was employed to quantify the cytokine response induced by the VLPs administered intramuscularly into BALB/c mice (n = 8). CD spectroscopy of Nc-aD-Sf9 VLPs showed that the secondary structure of the VLPs predominantly consisted of beta (β)-sheets (44.8%), and they were thermally stable up to ~52 °C. ELISA revealed that the aD epitope of the VLPs was significantly antigenic to anti-HBV surface antigen (HBsAg) antibodies. In addition, multiplex ELISA of serum samples from the vaccinated mice showed a significant induction (p < 0.001) of IFN-γ, IL-4, IL-5, IL-6, IL-10, and IL-12p70. This cytokine profile is indicative of natural killer cell, macrophage, dendritic cell and cytotoxic T-lymphocyte activities, which suggests a prophylactic innate and adaptive cellular immune response mediated by Nc-aD-Sf9 VLPs. Interestingly, Nc-aD-Sf9 induced a more robust release of the aforementioned cytokines than that of Nc-aD VLPs produced in Escherichia coli and a commercially used hepatitis B vaccine. Overall, Nc-aD-Sf9 VLPs are thermally stable and significantly antigenic, demonstrating their potential as an HBV vaccine candidate.
    Matched MeSH terms: Hepatitis B virus/immunology*
  14. Fulltext Practical approach in hepatitis B e antigen-negative individuals to identify treatment candidates
    Azmi AN, Tan SS, Mohamed R
    World J Gastroenterol, 2014 Sep 14;20(34):12045-55.
    PMID: 25232242 DOI: 10.3748/wjg.v20.i34.12045
    The natural history of chronic hepatitis B is characterized by different phases of infection, and patients may evolve from one phase to another or may revert to a previous phase. The hepatitis B e antigen (HBeAg)-negative form is the predominant infection worldwide, which consists of individuals with a range of viral replication and liver disease severity. Although alanine transaminase (ALT) remains the most accessible test available to clinicians for monitoring the liver disease status, further evaluations are required for some patients to assess if treatment is warranted. Guidance from practice guidelines together with thorough investigations and classifications of patients ensure recognition of who needs which level of care. This article aims to assist physicians in the assessment of HBeAg-negative individuals using liver biopsy or non-invasive tools such as hepatitis B s antigen quantification and transient elastography in addition to ALT and hepatitis B virus DNA, to identify who will remain stable, who will reactivate or at risk of disease progression hence will benefit from timely initiation of anti-viral therapy.
    Matched MeSH terms: Hepatitis B virus/immunology
  15. Fulltext Phage display creates innovative applications to combat hepatitis B virus
    Tan WS, Ho KL
    World J Gastroenterol, 2014 Sep 7;20(33):11650-70.
    PMID: 25206271 DOI: 10.3748/wjg.v20.i33.11650
    Hepatitis B virus (HBV) has killed countless lives in human history. The invention of HBV vaccines in the 20(th) century has reduced significantly the rate of the viral infection. However, currently there is no effective treatment for chronic HBV carriers. Newly emerging vaccine escape mutants and drug resistant strains have complicated the viral eradication program. The entire world is now facing a new threat of HBV and human immunodeficiency virus co-infection. Could phage display provide solutions to these life-threatening problems? This article reviews critically and comprehensively the innovative and potential applications of phage display in the development of vaccines, therapeutic agents, diagnostic reagents, as well as gene and drug delivery systems to combat HBV. The application of phage display in epitope mapping of HBV antigens is also discussed in detail. Although this review mainly focuses on HBV, the innovative applications of phage display could also be extended to other infectious diseases.
    Matched MeSH terms: Hepatitis B virus/immunology
  16. Fulltext PreS1 Mutations Alter the Large HBsAg Antigenicity of a Hepatitis B Virus Strain Isolated in Bangladesh
    Hossain MG, Mahmud MM, Nazir KHMNH, Ueda K
    Int J Mol Sci, 2020 Jan 15;21(2).
    PMID: 31952213 DOI: 10.3390/ijms21020546
    Mutations in the hepatitis B virus (HBV) genome can potentially lead to vaccination failure, diagnostic escape, and disease progression. However, there are no reports on viral gene expression and large hepatitis B surface antigen (HBsAg) antigenicity alterations due to mutations in HBV isolated from a Bangladeshi population. Here, we sequenced the full genome of the HBV isolated from a clinically infected patient in Bangladesh. The open reading frames (ORFs) (P, S, C, and X) of the isolated HBV strain were successfully amplified and cloned into a mammalian expression vector. The HBV isolate was identified as genotype C (sub-genotype C2), serotype adr, and evolutionarily related to strains isolated in Indonesia, Malaysia, and China. Clinically significant mutations, such as preS1 C2964A, reverse transcriptase domain I91L, and small HBsAg N3S, were identified. The viral P, S, C, and X genes were expressed in HEK-293T and HepG2 cells by transient transfection with a native subcellular distribution pattern analyzed by immunofluorescence assay. Western blotting of large HBsAg using preS1 antibody showed no staining, and preS1 ELISA showed a significant reduction in reactivity due to amino acid mutations. This mutated preS1 sequence has been identified in several Asian countries. To our knowledge, this is the first report investigating changes in large HBsAg antigenicity due to preS1 mutations.
    Matched MeSH terms: Hepatitis B virus/immunology*
  17. Detection of hepatitis B virus core antigen by phage display mediated TaqMan real-time immuno-PCR
    Monjezi R, Tan SW, Tey BT, Sieo CC, Tan WS
    J Virol Methods, 2013 Jan;187(1):121-6.
    PMID: 23022731 DOI: 10.1016/j.jviromet.2012.09.017
    The core antigen (HBcAg) of hepatitis B virus (HBV) is one of the markers for the identification of the viral infection. The main purpose of this study was to develop a TaqMan real-time detection assay based on the concept of phage display mediated immuno-PCR (PD-IPCR) for the detection of HBcAg. PD-IPCR combines the advantages of immuno-PCR (IPCR) and phage display technology. IPCR integrates the versatility of enzyme-linked immunosorbent assay (ELISA) with the sensitivity and signal generation power of PCR. Whereas, phage display technology exploits the physical association between the displayed peptide and the encoding DNA within the same phage particle. In this study, a constrained peptide displayed on the surface of an M13 recombinant bacteriophage that interacts tightly with HBcAg was applied as a diagnostic reagent in IPCR. The phage displayed peptide and its encoding DNA can be used to replace monoclonal antibody (mAb) and chemically bound DNA, respectively. This method is able to detect as low as 10ng of HBcAg with 10(8)pfu/ml of the recombinant phage which is about 10,000 times more sensitive than the phage-ELISA. The PD-IPCR provides an alternative means for the detection of HBcAg in human serum samples.
    Matched MeSH terms: Hepatitis B virus/immunology*
  18. Occult hepatitis B infection in blood donors from South East Asia: molecular characterisation and potential mechanisms of occurrence
    Candotti D, Lin CK, Belkhiri D, Sakuldamrongpanich T, Biswas S, Lin S, et al.
    Gut, 2012 Dec;61(12):1744-53.
    PMID: 22267593 DOI: 10.1136/gutjnl-2011-301281
    To investigate the molecular basis of occult hepatitis B virus (HBV) infection (OBI) in Asian blood donors.
    Matched MeSH terms: Hepatitis B virus/immunology
  19. Diversity of hepatitis B virus infecting Malaysian candidate blood donors is driven by viral and host factors
    Meldal BH, Bon AH, Prati D, Ayob Y, Allain JP
    J Viral Hepat, 2011 Feb;18(2):91-101.
    PMID: 20196797 DOI: 10.1111/j.1365-2893.2010.01282.x
    Malaysia is a medium endemic country for hepatitis B virus (HBV) infection but little is known about HBV strains circulating in Malaysian blood donors. Viral load, HBsAg concentrations and nested PCR products from 84 HBV surface antigen (HBsAg) positive samples were analysed in detail. Median viral load was 3050 IU/mL and median HBsAg 1150 IU/mL. Fifty-six full genome, 20 pre-S/S, 1 S gene and six basic core promoter/precore-only sequences were obtained. Genotypes B and C were present at a ratio of 2:1, and two genotype D samples were obtained, both from donors of Indian background. Phylogenetically, genotype B was more diverse with subgenotypes B2-5, B7 and B8 present, while most genotype C strains were from subgenotype C1. Genotypes B and C were equally frequent in ethnic Malays, but 80% of strains from Chinese were genotype B. HBsAg concentrations were higher in genotype C than in genotype B, in Chinese than Malays and in donors under the age of 30. HBV vaccine escape substitutions (P120S/T, I126N and G145G) were present in six strains. In the large surface protein, immuno-inactive regions were more mutated than CD8 epitopes and the major hydrophilic region. Strains of genotype B or from ethnic Malays had higher genetic diversity than strains of genotype C or from Chinese donors. Hence HBV strains circulating in Malaysia are phylogenetically diverse reflecting the ethnic mix of its population. Ethnic Malays carry lower HBsAg levels and higher genetic diversity of the surface antigen, possibly resulting in more effective immune control of the infection.
    Matched MeSH terms: Hepatitis B virus/immunology
  20. Fulltext Induction of humoral and cell-mediated immune responses by hepatitis B virus epitope displayed on the virus-like particles of prawn nodavirus
    Yong CY, Yeap SK, Goh ZH, Ho KL, Omar AR, Tan WS
    Appl Environ Microbiol, 2015 Feb;81(3):882-9.
    PMID: 25416760 DOI: 10.1128/AEM.03695-14
    Hepatitis B virus (HBV) is a deadly pathogen that has killed countless people worldwide. Saccharomyces cerevisiae-derived HBV vaccines based upon hepatitis B surface antigen (HBsAg) is highly effective. However, the emergence of vaccine escape mutants due to mutations on the HBsAg and polymerase genes has produced a continuous need for the development of new HBV vaccines. In this study, the "a" determinant within HBsAg was displayed on the recombinant capsid protein of Macrobrachium rosenbergii nodavirus (MrNV), which can be purified easily in a single step through immobilized metal affinity chromatography (IMAC). The purified protein self-assembled into virus-like particles (VLPs) when observed under a transmission electron microscope (TEM). Immunization of BALB/c mice with this chimeric protein induced specific antibodies against the "a" determinant. In addition, it induced significantly more natural killer and cytotoxic T cells, as well as an increase in interferon gamma (IFN-γ) secretion, which are vital for virus clearance. Collectively, these findings demonstrated that the MrNV capsid protein is a potential carrier for the HBV "a" determinant, which can be further extended to display other foreign epitopes. This paper is the first to report the application of MrNV VLPs as a novel platform to display foreign epitopes.
    Matched MeSH terms: Hepatitis B virus/immunology*
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