BACKGROUND Occult hepatitis B infection(OBI)is characterized by the detection of hepatitis B virus(HBV)DNA in serum(usually HBV DNA<200 IU/mL)or the liver but negativity for hepatitis B surface antigen(HBsAg).The d...BACKGROUND Occult hepatitis B infection(OBI)is characterized by the detection of hepatitis B virus(HBV)DNA in serum(usually HBV DNA<200 IU/mL)or the liver but negativity for hepatitis B surface antigen(HBsAg).The diagnosis of OBI relies on the sensitivity of assays used in the detection of HBV DNA and HBsAg.HBsAg assays with inadequate sensitivity or inability to detect HBV S variants may lead to misdiagnosis of OBI in people with overt HBV infection.CASE SUMMARY We report a HBsAg-negative but hepatitis B envelope antigen-positive patient who had a significant HBV DNA level.The patient was initially diagnosed as having OBI.However,sequence analysis revealed a unique insertion of amino acid residues at positions 120-124 in the S protein,which affects the formation of a disulfide bond that is associated with the formation of a loop.It is well known that there is an overlap between the S protein and Pol protein.We found that this new insertion site occurred in polymerase/reverse transcriptase domain,indi-cating that this insertion might be involved in HBV pathogenicity.The patient was finally diagnosed with a false OBI.CONCLUSION An insertion of amino acid residues at positions 120-124 of the S protein affects the formation of immunodominant epitopes and results in negative HBsAg levels.展开更多
The management of hepatitis B virus(HBV)infection now involves regular and appropriate monitoring of viral activity,disease progression,and treatment response.Traditional HBV infection biomarkers are limited in their ...The management of hepatitis B virus(HBV)infection now involves regular and appropriate monitoring of viral activity,disease progression,and treatment response.Traditional HBV infection biomarkers are limited in their ability to predict clinical outcomes or therapeutic effectiveness.Quantitation of HBV core antibodies(qAnti-HBc)is a novel non-invasive biomarker that may help with a variety of diagnostic issues.It was shown to correlate strongly with infection stages,hepatic inflammation and fibrosis,chronic infection exacerbations,and the presence of occult infection.Furthermore,qAnti-HBc levels were shown to be predictive of spontaneous or treatment-induced HBeAg and HBsAg seroclearance,relapse after medication termination,re-infection following liver transplantation,and viral reactivation in the presence of immunosuppression.qAnti-HBc,on the other hand,cannot be relied on as a single diagnostic test to address all problems,and its diagnostic and prognostic potential may be greatly increased when paired with qHBsAg.Commercial qAnti-HBc diagnostic kits are currently not widely available.Because many methodologies are only semi-quantitative,comparing data from various studies and defining universal cut-off values remains difficult.This review focuses on the clinical utility of qAnti-HBc and qHBsAg in chronic hepatitis B management.展开更多
The screening practices for hepatitis D virus(HDV)are diverse and nonstandardized worldwide,and the exact prevalence of HDV is uncertain.AIM To estimate HDV prevalence and investigate viral marker quantity trends in p...The screening practices for hepatitis D virus(HDV)are diverse and nonstandardized worldwide,and the exact prevalence of HDV is uncertain.AIM To estimate HDV prevalence and investigate viral marker quantity trends in patients with hepatitis D.METHODS We collected 5594 serum samples from patients with hepatitis B in Jilin Province,China(3293 males and 2301 females,age range of 2 to 89 years).We then conducted tests for hepatitis B surface antigen(HBsAg),hepatitis B Virus(HBV)DNA,anti-hepatitis D antigen(HDAg),and HDV RNA.RESULTS We found that the prevalence of anti-HDAg and HDV RNA among hepatitis B patient were 3.6%(3.2-4.2%)and 1.2%(0.9-1.5%),respectively,87.69%of hepatitis D patients were 51-70 years old.HDV infection screening positive rate of patients with HBV DNA levels below 2000 IU/mL(2.0%)was higher than those above 2000 IU/mL(0.2%).Among anti-HDAg positive patients,the HDV RNA positive rate was positively correlated with the HBsAg level and anti-HDAg level.There was a weak correlation between HBsAg and anti-HDAg levels among hepatitis D patients.CONCLUSION Our study highlights the importance of considering multiple factors when assessing the severity of HDV infection,comprehensive evaluation of patients’clinical and laboratory parameters is necessary for proper diagnosis and treatment.展开更多
A synthetic oligonucleotide, HSD-2a, encoding a peptide segment of the extracel-lular domain of a human sperm membrane protein, YWK-II, was fused with hepatitisB surface antigen gene (HBs gene ). The fused gene was th...A synthetic oligonucleotide, HSD-2a, encoding a peptide segment of the extracel-lular domain of a human sperm membrane protein, YWK-II, was fused with hepatitisB surface antigen gene (HBs gene ). The fused gene was then cloned to pUC18plasmid. The fused gene was prepared from the recombinant pUC18 plasmid byBamH I and Eco R I digestion, and then cloned into the transfer vector pGJP- 5 underthe control of P;., promoter, designated as pGJP-HSD/HBs. CV-1 cells were co-transfected with vaccinia virus (Tian Tan strain) and pGJP-HSD/IIBs and homolo-gous re combination occurred between the vaccinia virus TK gene of the plasmid flank-ing the foreign gene and the same sequences within the virus genome. TK phen0tyPerecombinant virus, vv-HSD/HBs, were selected from trandected HuTK' cells byplaque purthcation technique. The eopressi0n of HSD-b in spent medium and cellu-lar protein of HuTK cells infected with vv-HSD/HBs was determined by ELISAand Western-blot analysis using anti-rwK-II antiserum. The present study indicatesthat the vv-HSD/HBs seems promising as an antdertility vaccine.展开更多
Hepatitis B virus(HBV) infection is a global public health concern. HBV causes chronic infection in patients and can lead to liver cirrhosis, hepatocellular carcinoma, and other severe liver diseases. Thus, understand...Hepatitis B virus(HBV) infection is a global public health concern. HBV causes chronic infection in patients and can lead to liver cirrhosis, hepatocellular carcinoma, and other severe liver diseases. Thus, understanding HBV-related pathogenesis is of particular importance for prevention and clinical intervention. HBV surface antigens are indispensable for HBV virion formation and are useful viral markers for diagnosis and clinical assessment. During chronic HBV infection, HBV genomes may acquire and accumulate mutations and deletions, leading to the expression of defective HBV surface antigens. These defective HBV surface antigens have been found to play important roles in the progression of HBV-associated liver diseases. In this review, we focus our discussion on the nature of defective HBV surface antigen mutations and their contribution to the pathogenesis of fulminant hepatitis B. The relationship between defective surface antigens and occult HBV infection are also discussed.展开更多
BACKGROUND: Phage display technology has become a vital tool in studies aimed at identifying molecules binding to a specific target. It enables the rapid generation and selection of high affinity, fully human antibody...BACKGROUND: Phage display technology has become a vital tool in studies aimed at identifying molecules binding to a specific target. It enables the rapid generation and selection of high affinity, fully human antibody product candidates to essentially any disease target appropriate for antibody therapy. In this study, we prepared the recombinant single-chain fragment variable ( ScFv) antibody to hepatitis B virus surface antigen (HBsAg) by the phage display technology for obtaining a virus-targeting mediator. METHODS: mRNA was isolated from B-lymphocytes from a healthy volunteer and converted into cDNA. The fragment variables of heavy and light chain were amplified separately and assembled into ScFv DNA with a specially constructed DNA linker by polymerase chain reaction. The ScFv DNA was ligated into the phagmid vector pCANT-AB5E and the ligated sample was transformed into competent E. coli TG1. The transformed cells were infected with M13K07 helper phage to form a human recombinant phage antibody library. The volume and recombinant rate of the library were evaluated by bacterial colony count and restriction analysis. After two rounds of panning with HBsAg. the phage clones displaying ScFv of the antibody were selected by enzyme-linked immunosorbant assay ( ELISA) from the enriched phage clones. The antigen binding affinity of the positive clone was detected by competition ELISA. HB2151 E. coli was transfected with the positive phage clone demonstrated by competition ELISA for production of a soluble form of the anti-HBsAg ScFv. ELISA assay was used to detect the antigen binding affinity of the soluble anti-HBsAg ScFv. Finally, the relative molecular mass of soluble anti-HBsAg ScFv was measured by SDS-PAGE. RESULTS: The variable heavy ( VH ) and variable light (VL) and ScFv DNAs were about 340bp, 320bp and 750bp, respectively. The volume of the library was up to 2 × 106 and 8 of 10 random clones were recombinants. Two phage clones could strongly compete with the original HBsAb for binding to HBsAg. Within 2 strong positive phage clones, the soluble anti-HBsAg ScFv from one clone was found to have the binding activity with HBsAg. SDS-PAGE showed that the relative molecular weight of soluble anti-HBsAg ScFv was 32 kDa. CONCLUSION: The anti-HBsAg ScFv successfully produced by phage antibody technology may be useful for broadening the scope of application of the antibody.展开更多
AIM: To explore the anti-hepatitis B virus effect of RNA interference (RNAi) using small hairpin RNA (shRNA)expression vector.METHODS: Hepatitis B virus surface antigen green fluorescent protein (HBs-GFP) fusion vecto...AIM: To explore the anti-hepatitis B virus effect of RNA interference (RNAi) using small hairpin RNA (shRNA)expression vector.METHODS: Hepatitis B virus surface antigen green fluorescent protein (HBs-GFP) fusion vector and shRNA expression vectors were constructed and cotransfected transiently into HepG2 cells. mRNAs extracted from HepG2 cells were detected by real-time PCR. Fluorescence of HBs-GFP protein was detected by fluorescence-activated cell sorting (FACS). The effective shRNA expression vector was transfected into HepG2.2.15 cells. HBsAg and HBeAg in HepG2.2.15 cells were analyzed by radioimmunoassay (RIA) method.RESULTS: FACS revealed that shRNA targeting at HBsAg reduced the GFP signal by 56% compared to the control.Real-time PCR showed that HBs-GFP mRNA extracted from HepG2 cells cotransfected with pAVU6+27 and HBs-GFP expression plasmids decreased by 90% compared to the empty vector control. The expressions of HBsAg and HBeAg were also inhibited by 43% and 64%, respectively.CONCLUSION: RNAi using shRNA expression vector can inhibit the expression of HBsAg, providing a fresh approach to screening the efficient small interfering RNAs (siRNAs).展开更多
Background and Objective: Little is known about the incidence of hepatitis B virus (HBV) infection in Hodgkin's lymphoma patients. This study was to evaluate the impact of HBV infection on the survival of Hodgkin&...Background and Objective: Little is known about the incidence of hepatitis B virus (HBV) infection in Hodgkin's lymphoma patients. This study was to evaluate the impact of HBV infection on the survival of Hodgkin's lymphoma patient. Methods: Clinical data of 120 Hodgkin's lymphoma patients treated at the Sun Yat-sen University Cancer Center between January 2004 and October 2007 were collected. The impact of prognostic factors including HBV infection on survival was examined by univariate and multivariate analyses. A log-rank test was used for univariate analysis and the Cox proportional hazards regression model was used for multivariate analysis. Results: Of the 120 patients, 18 (15.0%) were hepatitis B virus surface antigen (HBsAg)-positive. The HBsAg-positive patients had lower 5-year survival rate than did the HBsAg-negative ones (66.9% vs. 91.3%, P = 0.006). When the patients were divided into early-stage (Ⅰ+Ⅱ) and advanced-stage (Ⅲ+Ⅳ) groups, the 5-year survival rate was significantly different between the HBsAg-positive and -negative patients in early-stage group (64.8% vs. 96.0%, P < 0.001), while not significantly different in advanced-stage group (75.0% vs. 84.8%, P=0.667). Both univariate and multivariate analyses showed that radiotherapy and HBV infection were independent prognosis factors for the patients with early-stage Hodgkin's lymphoma (P=0.006 and 0.014, respectively). Conclusions: The incidence of HBV infection is similar between Hodgkin's lymphoma patients and normal population. HBV infection is an independent prognosis factor for survival in the patients with early-stage Hodgkin's lymphoma.展开更多
AIM: To investigate the correlation between hepatitis B virus surface antigen (HBsAg), hepatitis C virus (HCV) expression in hepatocellular carcinoma (HCC), the HAI score of the noncancerous region of the liver...AIM: To investigate the correlation between hepatitis B virus surface antigen (HBsAg), hepatitis C virus (HCV) expression in hepatocellular carcinoma (HCC), the HAI score of the noncancerous region of the liver and the serum Alpha fetoprotein (AFP) level. METHODS: The patterns of HBsAg and HCV in 100 cases of HCC and their surrounding liver tissues were studied on paraffin-embedded sections with immunohistochemistry, the histological status was determined by one pathologist and one surgeon simultaneously using the hepatitis activity index (HAIl score, and AFP was detected by radioimmunity. The study included 100 consecutive patients who underwent curative resection for HCC. Based on HBsAg and HCV expression, the patients were classified into 4 groups: patients positive for HBsAg (HBsAg group), patients positive for HCV (HCV group), patients negative for both HCV and HBsAg (NBNC group) and patients positive for both HBsAg and HCV (BC group). RESULTS: The BC group had significantly higher HAI scores than the other three groups. (BC 〉 HCV 〉 HBsAg 〉 NBNC). HBV and HCV virus infection was positively correlated with HAI (rs = 0.39, P = 0.00011. The positive rate of AFP (85.7%) and the value of AFP (541.2 ng/mL) in the group with HBV and HCV co-infection were the highest among the four groups. The positive rate (53.3%) of AFP and the value of AFP ( 53.3 ng/mL) in the group with none-infection of HBV and HCV were the lowest. HBV and HCV virus infection was positively correlated with AFP(rs = 0.38, P = 0.0001). CONCLUSION: The AFP increase in patients with liver cancer was positively correlated with the infection of HBV and HCV. The-serum AFP elevation by the infection of HBV and HCV is one of mechanisms which lead to hepatocarcinogenesis, and the antivirus intervening treatment of hepatitis is significant for the prognosis of liver cancer. From our Spearman's rank correlation analysis, we can conclude that the severity of virally induced inflammation is correlated with HBsAg and HCV expression in HCC tissues and noncancerous tissues. Prior co-infection of HBV in HCV patients may be an adverse risk factor for intrahepatic inflammation.展开更多
AIM To test whether a simple animal, Caenorhabditis elegans(C. elegans), can be used as an alternative model to study the interaction between hepatitis B virus antigens(HBs Ag) and host factors. METHODS Three plasmids...AIM To test whether a simple animal, Caenorhabditis elegans(C. elegans), can be used as an alternative model to study the interaction between hepatitis B virus antigens(HBs Ag) and host factors. METHODS Three plasmids that were able to express the large, middle and small forms of HBs Ags(LHBs Ag, MHBs Ag, and SHBs Ag, respectively) driven by a ubiquitous promoter(fib-1) and three that were able to express SHBs Ag driven by different tissue-specific promoters were constructed and microinjected into worms. The brood size, egglaying rate, and gonad development of transgenic worms were analyzed using microscopy. Levels of m RNA related to endoplasmic reticulum stress, enpl-1, hsp-4, pdi-3 and xbp-1, were determined using reverse transcription polymerase reaction(RT-PCRs) in three lines of transgenic worms and dithiothreitol(DTT)-treated wild-type worms. RESULTS Severe defects in egg-laying, decreases in brood size, and gonad retardation were observed in transgenic worms expressing SHBs Ag whereas moderate defects were observed in transgenic worms expressing LHBs Ag and MHBs Ag. RT-PCR analysis revealed that enpl-1, hsp-4 and pdi-3 transcripts were significantly elevated in worms expressing LHBs Ag and MHBs Ag and in wild-type worms pretreated with DTT. By contrast, only pdi-3 was increased in worms expressing SHBs Ag. To further determine which tissue expressing SHBs Ag could induce gonad retardation, we substituted the fib-1 promoter with three tissue-specific promoters(myo-2 for the pharynx, est-1 for the intestines and mec-7 for the neurons) and generated corresponding transgenic animals. Moderate defective phenotypes were observed in worms expressing SHBs Ag in the pharynx and intestines but not in worms expressing SHBs Ag in the neurons, suggesting that the secreted SHBs Ag may trigger a cross-talk signal between the digestive track and the gonad resulting in defective phenotypes. CONCLUSION Ectopic expression of three forms of HBs Ag that causes recognizable phenotypes in transgenic worms suggests that C. elegans can be used as an alternative model for studying virus-host interactions because the resulting phenotype is easily detected through microscopy.展开更多
The 5'-nontranslated leader(omega sequence) of Tobacco mosaic virus(TMV) was used as a translational enhancer sequence in the expression of the hepatitis B surface antigen(HBsAg) gene in transgenic ginseng call...The 5'-nontranslated leader(omega sequence) of Tobacco mosaic virus(TMV) was used as a translational enhancer sequence in the expression of the hepatitis B surface antigen(HBsAg) gene in transgenic ginseng callus cultures. The adr subtype HBsAg gene was placed under the control of the Cauliflower mosaic virus(CaMV) 35S promoter linking to the TMV leader sequence. The antisense omega sequence was used in a control construct. The resulting constructs cloned in the binary vector pBI121 were used to transform the ginseng callus tissue via the Agrobacterium-mediated procedure. The integration and expression of the HBsAg gene were evaluated by PCR and western blot, respectively. Enzyme-linked immunoassays(ELISA) using a monoclonal antibody directed against human serum-derived HBsAg revealed a three to four-fold enhanced expression of HBsAg in ginseng cells conferred by the TMV omega element.展开更多
Hepatitis B virus (HBV) is one of the major causes of chronic hepatitis, cirrhosis and liver cancer. In combating HBV infections, HBV diagnosis and vaccination are therefore critical. The hepatitis B virus surface ant...Hepatitis B virus (HBV) is one of the major causes of chronic hepatitis, cirrhosis and liver cancer. In combating HBV infections, HBV diagnosis and vaccination are therefore critical. The hepatitis B virus surface antigen (HBsAg) is a key target molecule in developing vaccines and diagnostic systems. To date, although HBsAg has been expressed in bacteria, yeasts and mammalian cells, there are still limitations in the existing ones, which leave the necessity for searching new HBsAg production methods. In this study, a simple phage display-based method was developed to produce the purified full-length HBsAg molecules for further immunization studies. For this purpose, the HBsAg coding gene was cloned into a pCANTAB5E phagemid vector and expressed on the surface of M13 filamentous phages. The HBsAg-expressing phage nanosystem was then used as immunization agent in BALB/cJ mice. The ELISA results for sera obtained from mice immunized with HBsAg-displaying phage particles revealed an immune response against HBsAg. These results demonstrate the potential use of a full-length antigen to be displayed on phages as cost effective adjuvant-free immunization agents as an alternative to the highly purified and more expensive antigens conjugated with carrier molecules.展开更多
BACKGROUND Hepatitis B virus(HBV)is a known carcinogen that may be involved in pancreatic cancer development.Detection of HBV biomarkers[especially expression of HBV regulatory X protein(HBx)]within the tumor tissue m...BACKGROUND Hepatitis B virus(HBV)is a known carcinogen that may be involved in pancreatic cancer development.Detection of HBV biomarkers[especially expression of HBV regulatory X protein(HBx)]within the tumor tissue may provide direct support for this.However,there is still a lack of such reports,particularly in non-endemic regions for HBV infection.Here we present two cases of patients with pancreatic ductal adenocarcinoma,without a history of viral hepatitis,in whom the markers of HBV infection were detected in blood and in the resected pancreatic tissue.CASE SUMMARY The results of examination of two patients with pancreatic cancer,who gave informed consent for participation and publication,were the source for this study.Besides standards of care,special examination to reveal occult HBV infection was performed.This included blood tests for HBsAg,anti-HBc,anti-HBs,HBV DNA,and pancreatic tissue examinations with polymerase chain reaction for HBV DNA,pregenomic HBV RNA(pgRNA HBV),and covalently closed circular DNA HBV(cccDNA)and immunohistochemistry staining for HBxAg and Ki-67.Both subjects were operated on due to pancreatic ductal adenocarcinoma and serum HBsAg was not detected.However,in both of them anti-HBc antibodies were detected in blood,although HBV DNA was not found.Examination of the resected pancreatic tissue gave positive results for HBV DNA,expression of HBx,and active cellular proliferation by Ki-67 index in both cases.However,HBV pgRNA and cccDNA were detected only in case 1.CONCLUSION These cases may reflect potential involvement of HBV infection in the development of pancreatic cancer.展开更多
The risk of reactivation in patients with chronic or past/resolved hepatitis B virus(HBV)infection receiving chemotherapy or immunosuppressive drugs is a wellknown possibility.The indication of antiviral prophylaxis w...The risk of reactivation in patients with chronic or past/resolved hepatitis B virus(HBV)infection receiving chemotherapy or immunosuppressive drugs is a wellknown possibility.The indication of antiviral prophylaxis with nucleo(t)side analogue is given according to the risk of HBV reactivation of the prescribed therapy.Though the advent of new drugs is occurring in all the field of medicine,in the setting of hematologic malignancies the last few years have been characterized by several drug classes and innovative cellular treatment.As novel therapies,there are few data about the rate of HBV reactivation and the decision of starting or not an antiviral prophylaxis could be challenging.Moreover,patients are often treated with a combination of different drugs,so evaluating the actual role of these new therapies in increasing the risk of HBV reactivation is difficult.First results are now available,but further studies are still needed.Patients with chronic HBV infection[hepatitis B surface antigen(HBsAg)positive]are reasonably all treated.Past/resolved HBV patients(HBsAg negative)are the actual area of uncertainty where it could be difficult choosing between prophylaxis and pre-emptive strategy.展开更多
BACKGROUND In endemic areas,vertical transmission of hepatitis B virus(HBV)remains a major source of the global reservoir of infected people.Eliminating mother-to-child transmission(MTCT)of HBV is at the heart of Worl...BACKGROUND In endemic areas,vertical transmission of hepatitis B virus(HBV)remains a major source of the global reservoir of infected people.Eliminating mother-to-child transmission(MTCT)of HBV is at the heart of World Health Organization’s goal of reducing the incidence of HBV in children to less than 0.1%by 2030.Universal screening for hepatitis B during pregnancy and neonatal vaccination are the main preventive measures.AIM To evaluate the efficacy of HBV vaccination combined with one dose of immunoglobulin in children born to hepatitis B surface antigen(HBsAg)-positive mothers in Djibouti city.METHODS We conducted a study in a prospective cohort of HBsAg-positive pregnant women and their infants.The study ran from January 2021 to May 2022,and infants were followed up to 7 mo of age.HBV serological markers and viral load in pregnant women were measured using aVidas microparticle enzyme-linked immunosorbent assay(Biomérieux,Paris,France)and the automated Amplix platform(Biosynex,Strasbourg,France).All infants received hepatitis B immunoglobulin and were vaccinated against HBV at birth.These infants were closely monitored to assess their seroprotective response and for failure of immunoprophylaxis.Simple logistic regression was also used to identify risk factors associated with immunoprophylaxis failure and poor vaccine response.All statistical analyses were performed with version 4.0.1 of the R software.RESULTS Of the 50 pregnant women recruited,the median age was 31 years,ranging from 18 years to 41 years.The MTCT rate in this cohort was 4%(2/50)in HBsAg-positive women and 67%(2/3)in hepatitis B e antigen-positive women with a viral load>200000 IU/mL.Of the 48 infants who did not fail immunoprophylaxis,8(16%)became poor responders(anti-HB<100 mIU/mL)after HBV vaccination and hepatitis B immunoglobulin,while 40(84%)infants achieved a good level of seroprotection(anti-HB>100 mIU/mL).Factors associated with this failure of immunoprophylaxis were maternal HBV DNA levels(>200000 IU/mL)and hepatitis B e antigen-positive status(odds ratio=158,95%confidence interval:5.05-4958,P<0.01).Birth weight<2500 g was associated with a poor immune response to vaccination(odds ratio=34,95%confidence interval:3.01-383.86,P<0.01).CONCLUSION Despite a failure rate of immunoprophylaxis higher than the World Health Organization target,this study showed that the combination of immunoglobulin and HBV vaccine was effective in preventing MTCT of HBV.Therefore,further studies are needed to better understand the challenges associated with immunoprophylaxis failure in infants in Djibouti city.展开更多
Hepatitis B Virus (HBV) infections affect about 400 million people globally and cause about 1.4 million deaths annually. The virus displays high levels of genetic variations/mutations, some of which are immune escape ...Hepatitis B Virus (HBV) infections affect about 400 million people globally and cause about 1.4 million deaths annually. The virus displays high levels of genetic variations/mutations, some of which are immune escape mutants. The prevalence of HBV infection in Kenya is high at about 8%. This study aimed at identifying and characterizing HBV immune escape mutants in Kenya. From 547 HBV sequences available in Kenya in NCBI, and HBVdb databases in July 2021, 120 full sequences were retrieved. The S gene sequences at position 1-225, which included the “a” determinant region of the gene were analyzed using various bioinformatics tools such as Bioedit software, and Emboss Cons. The clinical significance was flagged from the search of peer-reviewed journals. Forty-six HBV-positive blood donor samples were obtained from the Kenya National Blood Transfusion Services without personal identifiers, DNA extracted, and sequenced targeting positions 1 to 520 of S genes. Mutations were similarly identified from seventeen sequences after cleaning and analysis. Out of 120 sequences that were extracted from databases and analyzed, 79 different mutations were identified. Fifteen of them were of clinical importance with an occurrence frequency of at least 5% were obtained. The majority (64.6%, n = 51), with S207N and A194V being most dominant, could result in immune escape and reduced HBsAg detection signals while 24.1% (n = 19) could result in immune escape/reduced HBsAg detection signals and high probability of hepatocellular carcinoma. Most likely to occur on the amino acids Alanine, Lysine, Serine, Asparagine, and Valine in decreasing order. The most dominant genotype was found to be Genotype A (N = 10), while four sequences were Genotype D. In contrast to the in-silico studies, the sequences from HBV samples from blood donors did not demonstrate the presence of S207N and A194V mutations and all the genotypes were type A1. Only two (13.3%) samples showed the same mutations of sK122R and sT143S for both in-silico analysis and actual sequenced samples. This study did not identify G145R mutation which is the commonest mutation within the HBsAg immunodominant “a” determinant that is associated with immune escape. The concordance of mutations in “a” determinant region of HBsAg gene among various studies is minimal. The study identified new mutations (sA194Y, sS207, sA194S, sS207I, sP46A, sA194T, sS207I, sP46R, and sT143P) that had not been published before. Four (20%) of the mutations were clinically significant. These included sS207R, sT143S, sC76F and sK122R.展开更多
BACKGROUND The relationship between hepatitis B surface antigen(HBsAg)-positive carrier status and liver cancer has been extensively studied.However,the epigenetic changes that occur during progression from HBsAg-posi...BACKGROUND The relationship between hepatitis B surface antigen(HBsAg)-positive carrier status and liver cancer has been extensively studied.However,the epigenetic changes that occur during progression from HBsAg-positive carrier status or cirrhosis to liver cancer are unknown.The epigenetic modification of DNA hydroxymethylation is critical in tumor development.Further,5-hydroxymethylcytosine(5hmC)is an important base for DNA demethylation and epigenetic regulation.It is also involved in the assembly of chromosomes and the regulation of gene expression.However,the mechanism of action of 5hmC in HBsAgpositive carriers or patients with cirrhosis who develop liver cancer has not been fully elucidated.AIM To investigate the possible epigenetic mechanism of HBsAg-positive carriers and hepatocellular carcinoma(HCC)progression from cirrhosis.METHODS Forty HBsAg-positive carriers,forty patients with liver cirrhosis,and forty patients with liver cancer admitted to the First People's Hospital of Yongkang between March 2020 and November 2021 were selected as participants.Free DNA was extracted using a cf-DNA kit.cfDNA was extracted by 5hmC DNA sequencing for principal component analysis,the expression profiles of the three groups of samples were detected,and the differentially expressed genes(DEGs)modified by hydroxymethylation were screened.Bioinformatic analysis was used to enrich DEGs,such as in biological pathways.RESULTS A total of 16455 hydroxymethylated genes were identified.Sequencing results showed that 32 genes had significant 5hmC modification differences between HBsAg carriers and liver cancer patients,of which 30 were upregulated and 2 downregulated in patients with HCC compared with HBsAg-positive carriers.Significant 5hmC modification differences between liver cirrhosis and liver cancer patients were identified in 20 genes,of which 17 were upregulated and 3 were downregulated in patients with HCC compared with those with cirrhosis.These genes may have potential loci that are undiscovered or unelucidated,which contribute to the development and progression of liver cancer.Analysis of gene ontology enrichment and Kyoto Encyclopedia of Genes and Genomes showed that the major signaling pathways involved in the differential genes were biliary secretion and insulin secretion.The analysis of protein interactions showed that the important genes in the protein-protein interaction network were phosphoenolpyruvate carboxykinase and solute carrier family 2.CONCLUSION The occurrence and development of liver cancer involves multiple genes and pathways,which may be potential targets for preventing hepatitis B carriers from developing liver cancer.展开更多
AIM:To better understand the clinical significance of hepatitis B seroiogic markers in babies born to hepatitis B surface antigen (HBsAg) positive mothers, the incidence of maternal seroiogic markers of hepatitis B vi...AIM:To better understand the clinical significance of hepatitis B seroiogic markers in babies born to hepatitis B surface antigen (HBsAg) positive mothers, the incidence of maternal seroiogic markers of hepatitis B via placenta and its transformation in these babies were investigated. METHODS: Mothers with positive HBsAg were selected in the third trimester of pregnancy. Their babies received immunoprophylaxis with hepatitis B immunoglobulin and hepatitis B vaccine after birth, and were consecutively followed up for hepatitis B seroiogic markers and HBV DNA at birth, mo 1, 4, 7, 12, and 24. RESULTS: Forty-two babies entered the study, including 16 born to hepatitis B e antigen (HBeAg)-positive HBsAg carrier mothers and 26 to HBeAg-negative HBsAg carrier mothers. Apart from four babies born to HBeAg-positive carrier mothers and demonstrated persistent positive HBeAg eventually became HBV carriers, all other babies developed anti-HBs before 12 mo of age. Among the other 12 babies born to HBeAg-positive carrier mothers, HBeAg was detected in 7 at birth, in 4 at mo 1, and in none of them thereafter. No antibody response to the transplacental HBeAg was detected. Among the babies born to HBeAg-negative carrier mothers, anti-HBe was detected 100% at birth and mo 1, in 88.5% at mo 4, in 46.2% at mo 7, in 4.2% at mo 12 and none in mo 24. Among all the immunoprophylaxis-protected babies born to either HBeAg-positive or HBeAg-negative carrier mothers, anti-HBc was detected in 100% at birth, mo 1 and mo 4, in 78.9% at mo 7, in 36.1% at mo 12 and in none at mo 24. CONCLUSION: HBeAg can pass through human placenta from mother to fetus and become undetectable before 4 mo of age, but no antibodies response to the transplacental HBeAg can be detected till mo 24 in the immunoprophylaxis-protected babies. The sole existence of anti-HBe before 1 year of age or anti-HBc before 2 years of age in babies born to HBsAg carrier mothers may simply represent the transplacental maternal antibodies, instead of indicators of HBV infection status.展开更多
AIM To investigate the utility of hepatitis B surface antigen(HBsAg) kinetics in chronic hepatitis B patients during long-term entecavir treatment.METHODS This retrospective study included treatment-na?ve chronic hepa...AIM To investigate the utility of hepatitis B surface antigen(HBsAg) kinetics in chronic hepatitis B patients during long-term entecavir treatment.METHODS This retrospective study included treatment-na?ve chronic hepatitis B patients who received at least 2 years of consecutive entecavir treatment. Patients were followed up at three to six month intervals with liver biochemistry, hepatitis B virus DNA, and abdominal sonography. In hepatitis B e antigen(HBeAg)-positive patients, HBeAg levels were assessed every three to six month until results became negative. Serum HBsAg levels were determined at the baseline, oneyear and five-year time points. Liver cirrhosis was diagnosed through liver biopsy, imaging examinations, or clinical findings of portal hypertension. Hepatocellular carcinoma was diagnosed by histological examination or dynamic image studies.RESULTS A total of 211 patients were enrolled. The median treatment time was 5.24(2.00-9.62) years. Multivariate analysis showed that lower baseline HBsAg levels were associated with an earlier virological response, earlier hepatitis B e antigen(HBeAg) seroconversion, and earlier biochemical response in HBeAg-positive patients(cut-off value: 4 log IU/mL) and an earlier virological response in HBeAg-negative non-cirrhotic patients(cut-off value: 2.4 log IU/mL). Although HBsAg levels decreased slowly during long-term entecavir treatment, higher HBsAg decrease rates were found in the first year for HBeAg-positive non-cirrhotic patients, and patients with higher baseline HBsAg levels. More favorable clinical outcomes were not observed by a rapid HBsAg decline per se, but depended on lower baseline HBsAg levels.CONCLUSION Baseline HBsAg can be used to predict treatment responses. HBsAg levels and decrease rates should be considered together according to disease status while interpreting HBsAg changes.展开更多
基金Supported by the Shanghai Municipal Commission of Health and Family Planning,No.PKJ2018-Y05.
文摘BACKGROUND Occult hepatitis B infection(OBI)is characterized by the detection of hepatitis B virus(HBV)DNA in serum(usually HBV DNA<200 IU/mL)or the liver but negativity for hepatitis B surface antigen(HBsAg).The diagnosis of OBI relies on the sensitivity of assays used in the detection of HBV DNA and HBsAg.HBsAg assays with inadequate sensitivity or inability to detect HBV S variants may lead to misdiagnosis of OBI in people with overt HBV infection.CASE SUMMARY We report a HBsAg-negative but hepatitis B envelope antigen-positive patient who had a significant HBV DNA level.The patient was initially diagnosed as having OBI.However,sequence analysis revealed a unique insertion of amino acid residues at positions 120-124 in the S protein,which affects the formation of a disulfide bond that is associated with the formation of a loop.It is well known that there is an overlap between the S protein and Pol protein.We found that this new insertion site occurred in polymerase/reverse transcriptase domain,indi-cating that this insertion might be involved in HBV pathogenicity.The patient was finally diagnosed with a false OBI.CONCLUSION An insertion of amino acid residues at positions 120-124 of the S protein affects the formation of immunodominant epitopes and results in negative HBsAg levels.
文摘The management of hepatitis B virus(HBV)infection now involves regular and appropriate monitoring of viral activity,disease progression,and treatment response.Traditional HBV infection biomarkers are limited in their ability to predict clinical outcomes or therapeutic effectiveness.Quantitation of HBV core antibodies(qAnti-HBc)is a novel non-invasive biomarker that may help with a variety of diagnostic issues.It was shown to correlate strongly with infection stages,hepatic inflammation and fibrosis,chronic infection exacerbations,and the presence of occult infection.Furthermore,qAnti-HBc levels were shown to be predictive of spontaneous or treatment-induced HBeAg and HBsAg seroclearance,relapse after medication termination,re-infection following liver transplantation,and viral reactivation in the presence of immunosuppression.qAnti-HBc,on the other hand,cannot be relied on as a single diagnostic test to address all problems,and its diagnostic and prognostic potential may be greatly increased when paired with qHBsAg.Commercial qAnti-HBc diagnostic kits are currently not widely available.Because many methodologies are only semi-quantitative,comparing data from various studies and defining universal cut-off values remains difficult.This review focuses on the clinical utility of qAnti-HBc and qHBsAg in chronic hepatitis B management.
基金the National Natural Science Foundation of Jilin Provence,No.YDZJ202201ZTYS016and Jilin Provincial Health Commission,No.2022JC053.
文摘The screening practices for hepatitis D virus(HDV)are diverse and nonstandardized worldwide,and the exact prevalence of HDV is uncertain.AIM To estimate HDV prevalence and investigate viral marker quantity trends in patients with hepatitis D.METHODS We collected 5594 serum samples from patients with hepatitis B in Jilin Province,China(3293 males and 2301 females,age range of 2 to 89 years).We then conducted tests for hepatitis B surface antigen(HBsAg),hepatitis B Virus(HBV)DNA,anti-hepatitis D antigen(HDAg),and HDV RNA.RESULTS We found that the prevalence of anti-HDAg and HDV RNA among hepatitis B patient were 3.6%(3.2-4.2%)and 1.2%(0.9-1.5%),respectively,87.69%of hepatitis D patients were 51-70 years old.HDV infection screening positive rate of patients with HBV DNA levels below 2000 IU/mL(2.0%)was higher than those above 2000 IU/mL(0.2%).Among anti-HDAg positive patients,the HDV RNA positive rate was positively correlated with the HBsAg level and anti-HDAg level.There was a weak correlation between HBsAg and anti-HDAg levels among hepatitis D patients.CONCLUSION Our study highlights the importance of considering multiple factors when assessing the severity of HDV infection,comprehensive evaluation of patients’clinical and laboratory parameters is necessary for proper diagnosis and treatment.
文摘A synthetic oligonucleotide, HSD-2a, encoding a peptide segment of the extracel-lular domain of a human sperm membrane protein, YWK-II, was fused with hepatitisB surface antigen gene (HBs gene ). The fused gene was then cloned to pUC18plasmid. The fused gene was prepared from the recombinant pUC18 plasmid byBamH I and Eco R I digestion, and then cloned into the transfer vector pGJP- 5 underthe control of P;., promoter, designated as pGJP-HSD/HBs. CV-1 cells were co-transfected with vaccinia virus (Tian Tan strain) and pGJP-HSD/IIBs and homolo-gous re combination occurred between the vaccinia virus TK gene of the plasmid flank-ing the foreign gene and the same sequences within the virus genome. TK phen0tyPerecombinant virus, vv-HSD/HBs, were selected from trandected HuTK' cells byplaque purthcation technique. The eopressi0n of HSD-b in spent medium and cellu-lar protein of HuTK cells infected with vv-HSD/HBs was determined by ELISAand Western-blot analysis using anti-rwK-II antiserum. The present study indicatesthat the vv-HSD/HBs seems promising as an antdertility vaccine.
基金supported by the National Nature Science Foundation of China,No.31770180the Youth Innovation Promotion Association CAS,No.2016303
文摘Hepatitis B virus(HBV) infection is a global public health concern. HBV causes chronic infection in patients and can lead to liver cirrhosis, hepatocellular carcinoma, and other severe liver diseases. Thus, understanding HBV-related pathogenesis is of particular importance for prevention and clinical intervention. HBV surface antigens are indispensable for HBV virion formation and are useful viral markers for diagnosis and clinical assessment. During chronic HBV infection, HBV genomes may acquire and accumulate mutations and deletions, leading to the expression of defective HBV surface antigens. These defective HBV surface antigens have been found to play important roles in the progression of HBV-associated liver diseases. In this review, we focus our discussion on the nature of defective HBV surface antigen mutations and their contribution to the pathogenesis of fulminant hepatitis B. The relationship between defective surface antigens and occult HBV infection are also discussed.
基金This study was supported by grants from the National Natural Science Foundation of China (No. 30572213)and Student Innovation Program of Shanxi Medical University (No.200404).
文摘BACKGROUND: Phage display technology has become a vital tool in studies aimed at identifying molecules binding to a specific target. It enables the rapid generation and selection of high affinity, fully human antibody product candidates to essentially any disease target appropriate for antibody therapy. In this study, we prepared the recombinant single-chain fragment variable ( ScFv) antibody to hepatitis B virus surface antigen (HBsAg) by the phage display technology for obtaining a virus-targeting mediator. METHODS: mRNA was isolated from B-lymphocytes from a healthy volunteer and converted into cDNA. The fragment variables of heavy and light chain were amplified separately and assembled into ScFv DNA with a specially constructed DNA linker by polymerase chain reaction. The ScFv DNA was ligated into the phagmid vector pCANT-AB5E and the ligated sample was transformed into competent E. coli TG1. The transformed cells were infected with M13K07 helper phage to form a human recombinant phage antibody library. The volume and recombinant rate of the library were evaluated by bacterial colony count and restriction analysis. After two rounds of panning with HBsAg. the phage clones displaying ScFv of the antibody were selected by enzyme-linked immunosorbant assay ( ELISA) from the enriched phage clones. The antigen binding affinity of the positive clone was detected by competition ELISA. HB2151 E. coli was transfected with the positive phage clone demonstrated by competition ELISA for production of a soluble form of the anti-HBsAg ScFv. ELISA assay was used to detect the antigen binding affinity of the soluble anti-HBsAg ScFv. Finally, the relative molecular mass of soluble anti-HBsAg ScFv was measured by SDS-PAGE. RESULTS: The variable heavy ( VH ) and variable light (VL) and ScFv DNAs were about 340bp, 320bp and 750bp, respectively. The volume of the library was up to 2 × 106 and 8 of 10 random clones were recombinants. Two phage clones could strongly compete with the original HBsAb for binding to HBsAg. Within 2 strong positive phage clones, the soluble anti-HBsAg ScFv from one clone was found to have the binding activity with HBsAg. SDS-PAGE showed that the relative molecular weight of soluble anti-HBsAg ScFv was 32 kDa. CONCLUSION: The anti-HBsAg ScFv successfully produced by phage antibody technology may be useful for broadening the scope of application of the antibody.
基金Supported by the National Natural Science Foundation of China, No. 30371270 the Major Program of Department of Science and Technology of Zhejiang Province, No. 2003C13015
文摘AIM: To explore the anti-hepatitis B virus effect of RNA interference (RNAi) using small hairpin RNA (shRNA)expression vector.METHODS: Hepatitis B virus surface antigen green fluorescent protein (HBs-GFP) fusion vector and shRNA expression vectors were constructed and cotransfected transiently into HepG2 cells. mRNAs extracted from HepG2 cells were detected by real-time PCR. Fluorescence of HBs-GFP protein was detected by fluorescence-activated cell sorting (FACS). The effective shRNA expression vector was transfected into HepG2.2.15 cells. HBsAg and HBeAg in HepG2.2.15 cells were analyzed by radioimmunoassay (RIA) method.RESULTS: FACS revealed that shRNA targeting at HBsAg reduced the GFP signal by 56% compared to the control.Real-time PCR showed that HBs-GFP mRNA extracted from HepG2 cells cotransfected with pAVU6+27 and HBs-GFP expression plasmids decreased by 90% compared to the empty vector control. The expressions of HBsAg and HBeAg were also inhibited by 43% and 64%, respectively.CONCLUSION: RNAi using shRNA expression vector can inhibit the expression of HBsAg, providing a fresh approach to screening the efficient small interfering RNAs (siRNAs).
文摘Background and Objective: Little is known about the incidence of hepatitis B virus (HBV) infection in Hodgkin's lymphoma patients. This study was to evaluate the impact of HBV infection on the survival of Hodgkin's lymphoma patient. Methods: Clinical data of 120 Hodgkin's lymphoma patients treated at the Sun Yat-sen University Cancer Center between January 2004 and October 2007 were collected. The impact of prognostic factors including HBV infection on survival was examined by univariate and multivariate analyses. A log-rank test was used for univariate analysis and the Cox proportional hazards regression model was used for multivariate analysis. Results: Of the 120 patients, 18 (15.0%) were hepatitis B virus surface antigen (HBsAg)-positive. The HBsAg-positive patients had lower 5-year survival rate than did the HBsAg-negative ones (66.9% vs. 91.3%, P = 0.006). When the patients were divided into early-stage (Ⅰ+Ⅱ) and advanced-stage (Ⅲ+Ⅳ) groups, the 5-year survival rate was significantly different between the HBsAg-positive and -negative patients in early-stage group (64.8% vs. 96.0%, P < 0.001), while not significantly different in advanced-stage group (75.0% vs. 84.8%, P=0.667). Both univariate and multivariate analyses showed that radiotherapy and HBV infection were independent prognosis factors for the patients with early-stage Hodgkin's lymphoma (P=0.006 and 0.014, respectively). Conclusions: The incidence of HBV infection is similar between Hodgkin's lymphoma patients and normal population. HBV infection is an independent prognosis factor for survival in the patients with early-stage Hodgkin's lymphoma.
文摘AIM: To investigate the correlation between hepatitis B virus surface antigen (HBsAg), hepatitis C virus (HCV) expression in hepatocellular carcinoma (HCC), the HAI score of the noncancerous region of the liver and the serum Alpha fetoprotein (AFP) level. METHODS: The patterns of HBsAg and HCV in 100 cases of HCC and their surrounding liver tissues were studied on paraffin-embedded sections with immunohistochemistry, the histological status was determined by one pathologist and one surgeon simultaneously using the hepatitis activity index (HAIl score, and AFP was detected by radioimmunity. The study included 100 consecutive patients who underwent curative resection for HCC. Based on HBsAg and HCV expression, the patients were classified into 4 groups: patients positive for HBsAg (HBsAg group), patients positive for HCV (HCV group), patients negative for both HCV and HBsAg (NBNC group) and patients positive for both HBsAg and HCV (BC group). RESULTS: The BC group had significantly higher HAI scores than the other three groups. (BC 〉 HCV 〉 HBsAg 〉 NBNC). HBV and HCV virus infection was positively correlated with HAI (rs = 0.39, P = 0.00011. The positive rate of AFP (85.7%) and the value of AFP (541.2 ng/mL) in the group with HBV and HCV co-infection were the highest among the four groups. The positive rate (53.3%) of AFP and the value of AFP ( 53.3 ng/mL) in the group with none-infection of HBV and HCV were the lowest. HBV and HCV virus infection was positively correlated with AFP(rs = 0.38, P = 0.0001). CONCLUSION: The AFP increase in patients with liver cancer was positively correlated with the infection of HBV and HCV. The-serum AFP elevation by the infection of HBV and HCV is one of mechanisms which lead to hepatocarcinogenesis, and the antivirus intervening treatment of hepatitis is significant for the prognosis of liver cancer. From our Spearman's rank correlation analysis, we can conclude that the severity of virally induced inflammation is correlated with HBsAg and HCV expression in HCC tissues and noncancerous tissues. Prior co-infection of HBV in HCV patients may be an adverse risk factor for intrahepatic inflammation.
基金Supported by Chang Gung Memorial Hospital,grants Nos.CMRPD1C0812,CMRPD1C0813 and BMRP742(to Lo SJ)
文摘AIM To test whether a simple animal, Caenorhabditis elegans(C. elegans), can be used as an alternative model to study the interaction between hepatitis B virus antigens(HBs Ag) and host factors. METHODS Three plasmids that were able to express the large, middle and small forms of HBs Ags(LHBs Ag, MHBs Ag, and SHBs Ag, respectively) driven by a ubiquitous promoter(fib-1) and three that were able to express SHBs Ag driven by different tissue-specific promoters were constructed and microinjected into worms. The brood size, egglaying rate, and gonad development of transgenic worms were analyzed using microscopy. Levels of m RNA related to endoplasmic reticulum stress, enpl-1, hsp-4, pdi-3 and xbp-1, were determined using reverse transcription polymerase reaction(RT-PCRs) in three lines of transgenic worms and dithiothreitol(DTT)-treated wild-type worms. RESULTS Severe defects in egg-laying, decreases in brood size, and gonad retardation were observed in transgenic worms expressing SHBs Ag whereas moderate defects were observed in transgenic worms expressing LHBs Ag and MHBs Ag. RT-PCR analysis revealed that enpl-1, hsp-4 and pdi-3 transcripts were significantly elevated in worms expressing LHBs Ag and MHBs Ag and in wild-type worms pretreated with DTT. By contrast, only pdi-3 was increased in worms expressing SHBs Ag. To further determine which tissue expressing SHBs Ag could induce gonad retardation, we substituted the fib-1 promoter with three tissue-specific promoters(myo-2 for the pharynx, est-1 for the intestines and mec-7 for the neurons) and generated corresponding transgenic animals. Moderate defective phenotypes were observed in worms expressing SHBs Ag in the pharynx and intestines but not in worms expressing SHBs Ag in the neurons, suggesting that the secreted SHBs Ag may trigger a cross-talk signal between the digestive track and the gonad resulting in defective phenotypes. CONCLUSION Ectopic expression of three forms of HBs Ag that causes recognizable phenotypes in transgenic worms suggests that C. elegans can be used as an alternative model for studying virus-host interactions because the resulting phenotype is easily detected through microscopy.
基金Science and Technology Development Planning Foundation of Jilin Province, China(No. 20030405)
文摘The 5'-nontranslated leader(omega sequence) of Tobacco mosaic virus(TMV) was used as a translational enhancer sequence in the expression of the hepatitis B surface antigen(HBsAg) gene in transgenic ginseng callus cultures. The adr subtype HBsAg gene was placed under the control of the Cauliflower mosaic virus(CaMV) 35S promoter linking to the TMV leader sequence. The antisense omega sequence was used in a control construct. The resulting constructs cloned in the binary vector pBI121 were used to transform the ginseng callus tissue via the Agrobacterium-mediated procedure. The integration and expression of the HBsAg gene were evaluated by PCR and western blot, respectively. Enzyme-linked immunoassays(ELISA) using a monoclonal antibody directed against human serum-derived HBsAg revealed a three to four-fold enhanced expression of HBsAg in ginseng cells conferred by the TMV omega element.
文摘Hepatitis B virus (HBV) is one of the major causes of chronic hepatitis, cirrhosis and liver cancer. In combating HBV infections, HBV diagnosis and vaccination are therefore critical. The hepatitis B virus surface antigen (HBsAg) is a key target molecule in developing vaccines and diagnostic systems. To date, although HBsAg has been expressed in bacteria, yeasts and mammalian cells, there are still limitations in the existing ones, which leave the necessity for searching new HBsAg production methods. In this study, a simple phage display-based method was developed to produce the purified full-length HBsAg molecules for further immunization studies. For this purpose, the HBsAg coding gene was cloned into a pCANTAB5E phagemid vector and expressed on the surface of M13 filamentous phages. The HBsAg-expressing phage nanosystem was then used as immunization agent in BALB/cJ mice. The ELISA results for sera obtained from mice immunized with HBsAg-displaying phage particles revealed an immune response against HBsAg. These results demonstrate the potential use of a full-length antigen to be displayed on phages as cost effective adjuvant-free immunization agents as an alternative to the highly purified and more expensive antigens conjugated with carrier molecules.
基金the Ministry of Science and Higher Education,No.FGMF-2022-0005the Russian Science Foundation,No.20-15-00373and the Moscow Healthcare Department,No.AAAA-A18-118021590196-1.
文摘BACKGROUND Hepatitis B virus(HBV)is a known carcinogen that may be involved in pancreatic cancer development.Detection of HBV biomarkers[especially expression of HBV regulatory X protein(HBx)]within the tumor tissue may provide direct support for this.However,there is still a lack of such reports,particularly in non-endemic regions for HBV infection.Here we present two cases of patients with pancreatic ductal adenocarcinoma,without a history of viral hepatitis,in whom the markers of HBV infection were detected in blood and in the resected pancreatic tissue.CASE SUMMARY The results of examination of two patients with pancreatic cancer,who gave informed consent for participation and publication,were the source for this study.Besides standards of care,special examination to reveal occult HBV infection was performed.This included blood tests for HBsAg,anti-HBc,anti-HBs,HBV DNA,and pancreatic tissue examinations with polymerase chain reaction for HBV DNA,pregenomic HBV RNA(pgRNA HBV),and covalently closed circular DNA HBV(cccDNA)and immunohistochemistry staining for HBxAg and Ki-67.Both subjects were operated on due to pancreatic ductal adenocarcinoma and serum HBsAg was not detected.However,in both of them anti-HBc antibodies were detected in blood,although HBV DNA was not found.Examination of the resected pancreatic tissue gave positive results for HBV DNA,expression of HBx,and active cellular proliferation by Ki-67 index in both cases.However,HBV pgRNA and cccDNA were detected only in case 1.CONCLUSION These cases may reflect potential involvement of HBV infection in the development of pancreatic cancer.
文摘The risk of reactivation in patients with chronic or past/resolved hepatitis B virus(HBV)infection receiving chemotherapy or immunosuppressive drugs is a wellknown possibility.The indication of antiviral prophylaxis with nucleo(t)side analogue is given according to the risk of HBV reactivation of the prescribed therapy.Though the advent of new drugs is occurring in all the field of medicine,in the setting of hematologic malignancies the last few years have been characterized by several drug classes and innovative cellular treatment.As novel therapies,there are few data about the rate of HBV reactivation and the decision of starting or not an antiviral prophylaxis could be challenging.Moreover,patients are often treated with a combination of different drugs,so evaluating the actual role of these new therapies in increasing the risk of HBV reactivation is difficult.First results are now available,but further studies are still needed.Patients with chronic HBV infection[hepatitis B surface antigen(HBsAg)positive]are reasonably all treated.Past/resolved HBV patients(HBsAg negative)are the actual area of uncertainty where it could be difficult choosing between prophylaxis and pre-emptive strategy.
基金Supported by the Attestation de Financement de These de Doctorat,Dakar le 28/10/2019.
文摘BACKGROUND In endemic areas,vertical transmission of hepatitis B virus(HBV)remains a major source of the global reservoir of infected people.Eliminating mother-to-child transmission(MTCT)of HBV is at the heart of World Health Organization’s goal of reducing the incidence of HBV in children to less than 0.1%by 2030.Universal screening for hepatitis B during pregnancy and neonatal vaccination are the main preventive measures.AIM To evaluate the efficacy of HBV vaccination combined with one dose of immunoglobulin in children born to hepatitis B surface antigen(HBsAg)-positive mothers in Djibouti city.METHODS We conducted a study in a prospective cohort of HBsAg-positive pregnant women and their infants.The study ran from January 2021 to May 2022,and infants were followed up to 7 mo of age.HBV serological markers and viral load in pregnant women were measured using aVidas microparticle enzyme-linked immunosorbent assay(Biomérieux,Paris,France)and the automated Amplix platform(Biosynex,Strasbourg,France).All infants received hepatitis B immunoglobulin and were vaccinated against HBV at birth.These infants were closely monitored to assess their seroprotective response and for failure of immunoprophylaxis.Simple logistic regression was also used to identify risk factors associated with immunoprophylaxis failure and poor vaccine response.All statistical analyses were performed with version 4.0.1 of the R software.RESULTS Of the 50 pregnant women recruited,the median age was 31 years,ranging from 18 years to 41 years.The MTCT rate in this cohort was 4%(2/50)in HBsAg-positive women and 67%(2/3)in hepatitis B e antigen-positive women with a viral load>200000 IU/mL.Of the 48 infants who did not fail immunoprophylaxis,8(16%)became poor responders(anti-HB<100 mIU/mL)after HBV vaccination and hepatitis B immunoglobulin,while 40(84%)infants achieved a good level of seroprotection(anti-HB>100 mIU/mL).Factors associated with this failure of immunoprophylaxis were maternal HBV DNA levels(>200000 IU/mL)and hepatitis B e antigen-positive status(odds ratio=158,95%confidence interval:5.05-4958,P<0.01).Birth weight<2500 g was associated with a poor immune response to vaccination(odds ratio=34,95%confidence interval:3.01-383.86,P<0.01).CONCLUSION Despite a failure rate of immunoprophylaxis higher than the World Health Organization target,this study showed that the combination of immunoglobulin and HBV vaccine was effective in preventing MTCT of HBV.Therefore,further studies are needed to better understand the challenges associated with immunoprophylaxis failure in infants in Djibouti city.
文摘Hepatitis B Virus (HBV) infections affect about 400 million people globally and cause about 1.4 million deaths annually. The virus displays high levels of genetic variations/mutations, some of which are immune escape mutants. The prevalence of HBV infection in Kenya is high at about 8%. This study aimed at identifying and characterizing HBV immune escape mutants in Kenya. From 547 HBV sequences available in Kenya in NCBI, and HBVdb databases in July 2021, 120 full sequences were retrieved. The S gene sequences at position 1-225, which included the “a” determinant region of the gene were analyzed using various bioinformatics tools such as Bioedit software, and Emboss Cons. The clinical significance was flagged from the search of peer-reviewed journals. Forty-six HBV-positive blood donor samples were obtained from the Kenya National Blood Transfusion Services without personal identifiers, DNA extracted, and sequenced targeting positions 1 to 520 of S genes. Mutations were similarly identified from seventeen sequences after cleaning and analysis. Out of 120 sequences that were extracted from databases and analyzed, 79 different mutations were identified. Fifteen of them were of clinical importance with an occurrence frequency of at least 5% were obtained. The majority (64.6%, n = 51), with S207N and A194V being most dominant, could result in immune escape and reduced HBsAg detection signals while 24.1% (n = 19) could result in immune escape/reduced HBsAg detection signals and high probability of hepatocellular carcinoma. Most likely to occur on the amino acids Alanine, Lysine, Serine, Asparagine, and Valine in decreasing order. The most dominant genotype was found to be Genotype A (N = 10), while four sequences were Genotype D. In contrast to the in-silico studies, the sequences from HBV samples from blood donors did not demonstrate the presence of S207N and A194V mutations and all the genotypes were type A1. Only two (13.3%) samples showed the same mutations of sK122R and sT143S for both in-silico analysis and actual sequenced samples. This study did not identify G145R mutation which is the commonest mutation within the HBsAg immunodominant “a” determinant that is associated with immune escape. The concordance of mutations in “a” determinant region of HBsAg gene among various studies is minimal. The study identified new mutations (sA194Y, sS207, sA194S, sS207I, sP46A, sA194T, sS207I, sP46R, and sT143P) that had not been published before. Four (20%) of the mutations were clinically significant. These included sS207R, sT143S, sC76F and sK122R.
基金Supported by Science and Technology Planning Project of Zhejiang Province,No.LGF20H160001.
文摘BACKGROUND The relationship between hepatitis B surface antigen(HBsAg)-positive carrier status and liver cancer has been extensively studied.However,the epigenetic changes that occur during progression from HBsAg-positive carrier status or cirrhosis to liver cancer are unknown.The epigenetic modification of DNA hydroxymethylation is critical in tumor development.Further,5-hydroxymethylcytosine(5hmC)is an important base for DNA demethylation and epigenetic regulation.It is also involved in the assembly of chromosomes and the regulation of gene expression.However,the mechanism of action of 5hmC in HBsAgpositive carriers or patients with cirrhosis who develop liver cancer has not been fully elucidated.AIM To investigate the possible epigenetic mechanism of HBsAg-positive carriers and hepatocellular carcinoma(HCC)progression from cirrhosis.METHODS Forty HBsAg-positive carriers,forty patients with liver cirrhosis,and forty patients with liver cancer admitted to the First People's Hospital of Yongkang between March 2020 and November 2021 were selected as participants.Free DNA was extracted using a cf-DNA kit.cfDNA was extracted by 5hmC DNA sequencing for principal component analysis,the expression profiles of the three groups of samples were detected,and the differentially expressed genes(DEGs)modified by hydroxymethylation were screened.Bioinformatic analysis was used to enrich DEGs,such as in biological pathways.RESULTS A total of 16455 hydroxymethylated genes were identified.Sequencing results showed that 32 genes had significant 5hmC modification differences between HBsAg carriers and liver cancer patients,of which 30 were upregulated and 2 downregulated in patients with HCC compared with HBsAg-positive carriers.Significant 5hmC modification differences between liver cirrhosis and liver cancer patients were identified in 20 genes,of which 17 were upregulated and 3 were downregulated in patients with HCC compared with those with cirrhosis.These genes may have potential loci that are undiscovered or unelucidated,which contribute to the development and progression of liver cancer.Analysis of gene ontology enrichment and Kyoto Encyclopedia of Genes and Genomes showed that the major signaling pathways involved in the differential genes were biliary secretion and insulin secretion.The analysis of protein interactions showed that the important genes in the protein-protein interaction network were phosphoenolpyruvate carboxykinase and solute carrier family 2.CONCLUSION The occurrence and development of liver cancer involves multiple genes and pathways,which may be potential targets for preventing hepatitis B carriers from developing liver cancer.
基金Supported by the Key-Subject Construction Project of Ministry of Public Health of China,No.97030223the young researcher grant from Children's Hospital of Fudan University,No.QN2001-5 Co-first-authors: Jian-She Wang and Hui Chen
文摘AIM:To better understand the clinical significance of hepatitis B seroiogic markers in babies born to hepatitis B surface antigen (HBsAg) positive mothers, the incidence of maternal seroiogic markers of hepatitis B via placenta and its transformation in these babies were investigated. METHODS: Mothers with positive HBsAg were selected in the third trimester of pregnancy. Their babies received immunoprophylaxis with hepatitis B immunoglobulin and hepatitis B vaccine after birth, and were consecutively followed up for hepatitis B seroiogic markers and HBV DNA at birth, mo 1, 4, 7, 12, and 24. RESULTS: Forty-two babies entered the study, including 16 born to hepatitis B e antigen (HBeAg)-positive HBsAg carrier mothers and 26 to HBeAg-negative HBsAg carrier mothers. Apart from four babies born to HBeAg-positive carrier mothers and demonstrated persistent positive HBeAg eventually became HBV carriers, all other babies developed anti-HBs before 12 mo of age. Among the other 12 babies born to HBeAg-positive carrier mothers, HBeAg was detected in 7 at birth, in 4 at mo 1, and in none of them thereafter. No antibody response to the transplacental HBeAg was detected. Among the babies born to HBeAg-negative carrier mothers, anti-HBe was detected 100% at birth and mo 1, in 88.5% at mo 4, in 46.2% at mo 7, in 4.2% at mo 12 and none in mo 24. Among all the immunoprophylaxis-protected babies born to either HBeAg-positive or HBeAg-negative carrier mothers, anti-HBc was detected in 100% at birth, mo 1 and mo 4, in 78.9% at mo 7, in 36.1% at mo 12 and in none at mo 24. CONCLUSION: HBeAg can pass through human placenta from mother to fetus and become undetectable before 4 mo of age, but no antibodies response to the transplacental HBeAg can be detected till mo 24 in the immunoprophylaxis-protected babies. The sole existence of anti-HBe before 1 year of age or anti-HBc before 2 years of age in babies born to HBsAg carrier mothers may simply represent the transplacental maternal antibodies, instead of indicators of HBV infection status.
文摘AIM To investigate the utility of hepatitis B surface antigen(HBsAg) kinetics in chronic hepatitis B patients during long-term entecavir treatment.METHODS This retrospective study included treatment-na?ve chronic hepatitis B patients who received at least 2 years of consecutive entecavir treatment. Patients were followed up at three to six month intervals with liver biochemistry, hepatitis B virus DNA, and abdominal sonography. In hepatitis B e antigen(HBeAg)-positive patients, HBeAg levels were assessed every three to six month until results became negative. Serum HBsAg levels were determined at the baseline, oneyear and five-year time points. Liver cirrhosis was diagnosed through liver biopsy, imaging examinations, or clinical findings of portal hypertension. Hepatocellular carcinoma was diagnosed by histological examination or dynamic image studies.RESULTS A total of 211 patients were enrolled. The median treatment time was 5.24(2.00-9.62) years. Multivariate analysis showed that lower baseline HBsAg levels were associated with an earlier virological response, earlier hepatitis B e antigen(HBeAg) seroconversion, and earlier biochemical response in HBeAg-positive patients(cut-off value: 4 log IU/mL) and an earlier virological response in HBeAg-negative non-cirrhotic patients(cut-off value: 2.4 log IU/mL). Although HBsAg levels decreased slowly during long-term entecavir treatment, higher HBsAg decrease rates were found in the first year for HBeAg-positive non-cirrhotic patients, and patients with higher baseline HBsAg levels. More favorable clinical outcomes were not observed by a rapid HBsAg decline per se, but depended on lower baseline HBsAg levels.CONCLUSION Baseline HBsAg can be used to predict treatment responses. HBsAg levels and decrease rates should be considered together according to disease status while interpreting HBsAg changes.