Hepatitis B surface antigen-negative but hepatitis B envelope antigen-positive false occult hepatitis B virus infection:A case report

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.

Quantitative hepatitis B core antibody and quantitative hepatitis B surface antigen:Novel viral biomarkers for chronic hepatitis B management

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.

Five novel monoclonal antibodies to thymic epithelial cell surface antigens in rats

OBJECTIVE: To establish monoclonal antibodies (mAbs) against thymic epithelial cells and study the function of epithelial cells during T-cell differentiation in the thymus. METHODS: Hybridomas secreting mAbs against thymic epithelial cells were derived by immunization of Balb/c mice with two thymic epithelial cell lines, TaD3 and FTE. The distribution of antigens recognized by these mAbs was detected by immunochemical staining and cytofluorographic analysis, and the molecular weight of the antigens by immunoblotting. RESULTS: Five specific monoclonal antibodies (mAb) were obtained. On the basis of their distribution in the thymus determined by immunochemical staining, mAb RE-4D8 was regarded as clusters of thymic epithelium staining (CTES) type IIA: mAb RE-12B2, which showed a unique distribution pattern only in the medulla, was CTES type V: mAb RE-5C6 was CTES type IV: mAb RE-6D6 might be CTES type IIB: and mAb RE-1D4 was classified as type V. The molecular weight (MW) of antigen RE-4D8, RE-6D6 and RE-12B2 were 120 kDa, 220 kDa and 35 kDa, respectively. Antigen RE-1D4 is a novel marker of cortical epithelium, several established thymic epithelial cell lines were classified and their original intrathymic locations were determined by these mAbs. Thymic cell lines, TuD3 and FTE were cortical phenotypes whereas TaD3 had a medullar phenotype. CONCLUSIONS: These mAbs clearly demonstrate the heterogeneity of the thymic epithelium; they could detect antigens not only in the cytoplasm but also on the surface of thymic epithelial cells. Our data suggest that these newly established mAbs may help elucidate the interaction between thymocytes and epithelial cells during T cell maturation.

Inhibition of hepatitis B virus surface antigen expression by small hairpin RNA in vitro

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).

Dopamine Inhibits the Expression of Hepatitis B Virus Surface and e Antigens by Activating the JAK/STAT Pathway and Upregulating Interferon-stimulated Gene 15 Expression

Background and Aims:Hepatitis B virus(HBV)infection is a major risk factor for cirrhosis and liver cancer,and its treatment continues to be difficult.We previously demonstrated that a dopamine analog inhibited the packaging of pregenomic RNA into capsids.The present study aimed to determine the effect of dopamine on the expressions of hepatitis B virus surface and e antigens(HBsAg and HBeAg,respectively)and to elucidate the underlying mechanism.Methods:We used dopamine-treated HBVinfected HepG2.2.15 and NTCP-G2 cells to monitor HBsAg and HBeAg expression levels.We analyzed interferon-stimulated gene 15(ISG15)expression in dopamine-treated cells.We knocked down ISG15 and then monitored HBsAg and HBeAg expression levels.We analyzed the expression of Janus kinase(JAK)/signal transducer and activator of transcription(STAT)pathway factors in dopamine-treated cells.We used dopamine hydrochloride-treated adeno-associated virus/HBV-infected mouse model to evaluate HBV DNA,HBsAg,and HBeAg expression.HBV virus was collected from HepAD38.7 cell culture medium.Results:Dopamine inhibited HBsAg and HBeAg expression and upregulated ISG15 expression in HepG2.2.15 and HepG2-NTCP cell lines.ISG15 knockdown increased HBsAg and HBeAg expression in HepG2.2.15 cells.Dopamine-treated cells activated the JAK/STAT pathway,which upregulated ISG15 expression.In the adeno-associated virus-HBV murine infection model,dopamine downregulated HBsAg and HBeAg expression and activated the JAK-STAT/ISG15 axis.Conclusions:Dopamine inhibits the expression of HBsAg and HBeAg by activating the JAK/STAT pathway and upregulating ISG15 expression.

Immunoprophylaxis failure and vaccine response in infants born to mothers with chronic hepatitis B infection in Djibouti

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.

Correlation of hepatitis B surface antigen expression with clinicopathological and biochemical parameters in liver biopsies: A comprehensive study

BACKGROUND Chronic viral B hepatitis(CHB)is a potentially life-threatening liver disease that may progress to liver failure and cirrhosis.Currently,although combinations of different laboratory methods are used in the follow-up and treatment of CHB,the failure of these procedures in some cases has led to the necessity of developing new approaches.In CHB,the intrahepatic expression pattern of viral antigens,including hepatitis B surface antigen(HBsAg),is related to different phases of inflammation.However,many studies have focused on the intracytoplasmic properties of HBsAg staining,and HBsAg positivity in liver tissue has not been evaluated by objective quantitative methods.AIM To investigate the relationship of image analysis-based quantitative HBsAg expression and its staining patterns with clinicopathological factors and treatment in CHB.METHODS A total of 140 liver biopsies from treatment-naïve cases with CHB infection were included in this study.Following diagnosis,all patients were treated with entecavir(0.5 mg)and followed up at three-month intervals.The percentage of immunohistochemical HBsAg(p-HBsAg)expression in the liver was determined in whole tissue sections of biopsies from each case by image analysis.The immunohistochemical staining pattern was also evaluated separately according to 3 different previously defined classifications.RESULTS A positive correlation between p-HBsAg and serum levels of hepatitis B virus(HBV)DNA and HBsAg was observed(P<0.001).The p-HBsAg value was significantly higher in younger patients than in older patients.When the groups were categorized according to the hepatitis B e antigen(HBeAg)status in HBeAgpositive cases,p-HBsAg was correlated with HBV DNA,hepatitis activity index(HAI)and fibrosis scores(P<0.001).In this group,p-HBsAg and HBsAg expression patterns were also correlated with the viral response(VR)and the serological response(SR)(P<0.001).Multivariate analysis revealed that p-HBsAg was an independent predictor of either VR or SR(P<0.001).In HBeAg-negative patients,although HBsAg expression patterns were correlated with both HAI and fibrosis,no relationship was observed among p-HBsAg,clinicopathological factors and VR.CONCLUSION In pretreatment liver biopsies,the immunohistochemical determination of HBsAg expression by quantitative methods,beyond its distribution within the cell,may be a good predictor of the treatment response,especially in HBeAg-positive cases.

Transformation of hepatitis B serologic markers in babies born to hepatitis B surface antigen positive mothers

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.

Hepatitis B surface antigen clearance in inactive hepatitis B surface antigen carriers treated with peginterferon alfa-2a

AIM: To examine the association between interferon(IFN) therapy and loss of hepatitis B surface antigen(HBs Ag) in inactive HBs Ag carriers. METHODS: This was a retrospective cohort study in inactive HBs Ag carriers, who were treatment-naive, with a serum HBs Ag level < 100 IU/m L and an undetectable hepatitis B virus(HBV) DNA level(< 100 IU/m L). All the 20 treated patients received subcutaneous PEG-IFN alfa-2a 180 μg/wk for 72 wk and were then followed for 24 wk. There were 40 untreated controls matched with 96 wk of observation. Serum HBs Ag, HBV DNA, and alanine aminotransferases were monitored every 3 mo in the treatment group and every 3-6 mo in the control group. RESULTS: Thirteen(65.0%) of 20 treated patients achieved HBs Ag loss, 12 of whom achieved HBs Ag seroconversion. Mean HBs Ag level in treated patients decreased to 6.69 ± 13.04 IU/m L after 24 wk of treatment from a baseline level of 26.22 ± 33.00 IU/m L. Serum HBV DNA level remained undetectable(< 100 IU/m L) in all treated patients during the study. HBs Ag level of the control group decreased from 25.72 ± 25.58 IU/m L at baseline to 17.11 ± 21.62 IU/m L at week 96(P = 0.108). In the control group, no patient experienced HBs Ag loss/seroconversion, and two(5.0%) developed HBV reactivation.CONCLUSION: IFN treatment results in HBs Ag loss and seroconversion in a considerable proportion of inactive HBs Ag carriers with low HBs Ag concentrations.

Hepatitis B surface antigen levels during natural history of chronic hepatitis B: A Chinese perspective study

AIM: To determine the baseline hepatitis B surface antigen (HBsAg) levels during the different phases of chronic hepatitis B (CHB) patients in China.

Screening and evaluation of human single-chain fragment variable antibody against hepatitis B virus surface antigen

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.

Serum hepatitis B surface antigen levels predict treatment response to nucleos(t)ide analogues

Quantification of hepatitis B surface antigen(HBsAg)has been suggested to be helpful in the management of chronic hepatitis B(CHB)patients.Nucleos(t)ide analogs(NAs)are the therapy of choice for CHB and are used in the majority of CHB patients.NAs are able to induce hepatitis B virus(HBV)viral suppression,normalization of alanine aminotransferase(ALT)levels,and improvement in liver histology.Automated quantitative assays for serum HBsAg have recently become available,facilitating standardized quantification of serum HBsAg.This has led to increased interest in the clinical application of quantitative serum HBsAg for predicting therapeutic response to NAs.Recent studies have shown that a decline in serum HBsAg levels in patients receiving peginterferon may signal successful induction of immune control over HBV,and can therefore be used to predict therapeutic response.NA treatment typically induces a less rapid decline in HBsAg than interferon treatment;it has been estimated that full HBsAg clearance can require decades of NA treatment.However,a rapid HBsAg decline during NA therapy may identify patients who will show clearance of HBsAg.Currently,there is no consensus on the clinical utility of serum HBsAg monitoring for evaluating patient responses to NA therapy.This review focuses on recent findings regarding the potential application of HBsAg quantification in the management of CHB patients receiving NA therapy.

Mutations in surface and polymerase gene of chronic hepatitis B patients with coexisting HBsAg and anti-HBs

AIM： To investigate the clinical significance and presence of mutations in the surface （S） and overlapping polymerase gene of hepatitis B patients with coexisting HBsAg and anti-HBs. METHODS： Twenty-three patients with chronic hepatitis B were studied. Of the 23 patients, i i were both positive for hepatitis B virus （HBV） surface antigen （HBsAg） and antibody to HBV surface antigen （anti-HBs）, 12 were negative for anti-HBs while positive for HBsAg. DNA was extracted from 200 μL serum of the patients. Nucleotide of the surface and overlapping polymerase gene from HBV-infected patients was amplified by PCR, and the PCR products were sequenced. RESULTS： Forty-one mutations were found within the surface gene protein of HBV in 15 patients （10 with coexisting HBsAg and anti-HBs）. Six （14.6%） out of 41 mutations were located at ＂α＂ determinant region in 5 patients （4 positive for HBsAg and anti-HBs）. Eleven mutations （26.8%） occurred in the downstream or upstream of ＂α＂ determinant region. Lamivudine （LMV）- selected mutations were found in three patients who developed anti-HBs, which occurred in amino acid positions （196, 198, 199） of the surface protein and in YMDD motif （M204I/V） of the polymerase protein simultaneously. Presence of these mutations did not relate to changes in ALT and HBV DNA levels.CONCLUSION： Besides mutations in the ＂α＂ determinant region, mutations at downstream or upstream of the ＂α＂ determinant region may contribute to the development of anti-HBs. These mutations do not block the replicating competency of HBV in the presence of high titer of anti-HBs.

Liver grafts from hepatitis B surface antigen-positive donors: A review of the literature

The scarcity of available organs and the gap between supply and demand continue to be the main limitations of liver transplantation. To relieve the organ shortage, current transplant strategies have implemented extended criteria, which include the use of liver from patients with signs of past or present hepatitis B virus(HBV) infection. While the use of liver grafts from donors with evidence of past HBV infection is quite limited, some data have been collected regarding the feasibility of transplanting a liver graft from a hepatitis B surface antigen(HBs Ag) positive donor. The aim of the present work was to review the literature regarding liver transplants from HBs Ag-positive donors. A total of 17 studies were identified by a search in Medline. To date, HBs Ag positive grafts have preferentially been allocated to HBs Ag positive recipients. The large majority of these patients continue to be HBs Ag positive despite the use of immunoglobulin, and infection prevention can only be guaranteed by using antiviral prophylaxis. Although serological persistence is evident, no significant HBV-related disease has been observed, except in patients coinfected with delta virus. Consistently less data are available for HBs Ag negative recipients, although they are mostly promising. HBs Agpositive grafts could be an additional organ source for liver transplantation, provided that the risk of reinfection/reactivation is properly prevented.

Intrahepatic distribution of hepatitis B virus antigens in patients with and without hepatocellular carcinoma

AIM: To study the intrahepatic expression of hepatitis B surface antigen (HBsAg) and hepatitis B core antigen (HBcAg) in chronic hepatitis B patients with and without hepatocellular carcinoma.METHODS: A total of 33 chronic hepatitis B patients (mean age of 40.3 &#x000b1; 2.5 years), comprising of 14 HBeAg positive and 19 HBeAg negative patients; and 13 patients with hepatitis B virus related hepatocellular carcinoma (mean age of 49.6 &#x000b1; 4.7 years), were included in our study. Immunohistochemical staining for HBcAg and HBsAg was done using standard streptavidin-biotin-immunoperoxidase technique on paraffin-embedded liver biopsies. The HBcAg and HBsAg staining distributions and patterns were described according to a modified classification system.RESULTS: Compared to the HBeAg negative patients, the HBeAg positive patients were younger, had higher mean HBV DNA and alanine transaminases levels. All the HBeAg positive patients had intrahepatic HBcAg staining; predominantly with &#x0201c;diffuse&#x0201d; distribution (79%) and &#x0201c;mixed cytoplasmic/nuclear&#x0201d; pattern (79%). In comparison, only 5% of the HBeAg-negative patients had intrahepatic HBcAg staining. However, the intrahepatic HBsAg staining has wider distribution among the HBeAg negative patients, namely; majority of the HBeAg negative cases had &#x0201c;patchy&#x0201d; HBsAg distribution compared to &#x0201c;rare&#x0201d; distribution among the HBeAg positive cases. All but one patient with HCC were HBeAg negative with either undetectable HBV DNA or very low level of viremia. Intrahepatic HBcAg and HBsAg were seen in 13 (100%) and 10 (77%) of the HCC patients respectively. Interestingly, among the 9 HCC patients on anti-viral therapy with suppressed HBV DNA, HBcAg and HBsAg were detected in tumor tissues but not the adjacent liver in 4 (44%) and 1 (11%) patient respectively.CONCLUSION: Isolated intrahepatic HBcAg and HBsAg can be present in tumors of patients with suppressed HBV DNA on antiviral therapy; that may predispose them to cancer development.

Differential reactivity of mouse monoclonal anti-HBs antibodies with recombinant mutant HBs antigens

AIM: To investigate the reactivity of a panel of 8 mouse anti-hepatitis B surface antigen (HBsAg) monoclonal antibodies (mAbs) using a collection of 9 recombinant HBsAg mutants with a variety of amino acid substitutions mostly located within the “a” region.METHODS: The entire HBs genes previously cloned into a mammalian expression vector were transiently transfected into COS7 cells. Two standard unmutated sequences of the ayw and adw subtypes served as controls. Secreted mutant proteins were collected and measured by three commercial diagnostic immunoassays to assess transfection efficiency. Reactivity of anti-HBs mAbs with mutated HBsAgs was determined by sandwich enzyme-linked immunosorbent assay (ELISA).RESULTS: Reactivity of anti-HBs mAbs with mutated HBsAgs revealed different patterns. While three mutants reacted strongly with all mAbs, two mutants reacted weakly with only two mAbs and the remaining proteins displayed variable degrees of reactivity towards different mAbs. Accordingly, four groups of mAbs with different but overlapping reactivity patterns could be envisaged. One group consisting of two mAbs (37C5-S7 and 35C6-S11) was found to recognize stable linear epitopes conserved in all mutants. Mutations outside the “a” determinant at positions 120 (P→S), 123(T→N) and 161(M→T) were found to affect reactivity of these mAbs.CONCLUSION: Our findings could have important implications for biophysical studies, vaccination strategies and immunotherapy of hepatitis B virus (HBV) mutants.

Long term follow-up and outcome of liver transplantation from hepatitis B surface antigen positive donors

Liver transplant for hepatitis B virus(HBV) currently yields excellent outcomes: it allows to rescue patients with an HBV-related advanced liver disease, resulting in a demographical modification of the waiting list for liver transplant. In an age of patient-tailored treatments, in liver transplantation as well the aim is to offer the best suitable graft to the patient who can benefit from it, also expanding the criteria for organ acceptance and allocation. With the intent of developing strategies to increase the donor pool, we set-up a multicenter study involving 3 Liver Transplant Centers in Italy: patients undergoing liver transplantation between March 03, 2004, and May 21, 2010, were retrospectively evaluated. 1408 patients underwent liver transplantation during the study period, 28(2%) received the graft from hepatitis B surface antigen positive(HBs Ag)-positive deceased donors. The average follow-up after liver transplantation was 63.7 mo [range: 0.1-119.4; SD ± 35.8]. None Primary nonfunction, re-liver transplantation, early or late hepatic artery thrombosis occurred. The 1-, 3-and 5-year graft and patient survival resulted of 85.7%, 82.1%, 78.4%. Our results suggest that the use of HBs Agpositive donors liver grafts is feasible, since HBV can be controlled without affecting graft stability. However, the selection of grafts and the postoperative antiviral therapy should be managed appropriately.

Hepatitis B surface antigen seroconversion after HBV reactivation in non-Hodgkin's lymphoma

Reactivation of hepatitis B virus(HBV)can occur in lymphoma patients infected with HBV when they receive chemotherapy or immunotherapy.Prophylactic administration of lamivudine(LAM)reduces the morbidity and mortality associated with HBV reactivation.However,what defines HBV reactivation and the optimal duration of treatment with LAM have not yet been clearly established.HBV reactivation may occur due to the cessation of prophylactic LAM,although re-treatment with nucleoside analogs may sometimes result in hepatitis B surface antigen(HBsAg)seroconversion,which is a satisfactory endpoint for the management of HBV infection.We report a case of HBV reactivation in a 68-year-old HBsAg-positive patient who received rituximab-based immunochemotherapy for follicular lymphoma.HBV reactivation developed following cessation of prophylactic LAM therapy.The patient subsequently received treatment with entecavir(ETV),which led to a rapid and sustained suppression of HBV replication and HBsAg seroconversion.We also appraised the literature concerning HBV reactivation and the role of ETV in the management of HBV reactivation in lymphoma patients.A total of 28 cases of HBV reactivation have been reported as having been treated with ETV during or after immunosuppressive chemotherapy in lymphoma patients.We conclude that ETV is an efficacious and safe treatment for HBV reactivation following LAM cessation in lymphoma patients treated with rituximab-based immunochemotherapy.

Seroprevalence of hepatitis B surface antigen in pregnant women attending antenatal clinic in Honiara Solomon Islands,2015

AIMTo determine the seroprevalence of hepatitis B surface antigen (HBsAg) among pregnant women attending antenatal clinic in Honiara, Solomon Islands. METHODSThis descriptive cross-sectional study was carried out in seven area health centers in Honiara. From March to June 2015, identification of eligible pregnant women in each site was conducted using systematic random sampling technique. A total of 243 pregnant women who gave written informed consent were enrolled. Standardized tool was used to record demographics, obstetric history and serology results. HBsAg and hepatitis B e antigen (HBeAg) were tested using point-of-care rapid diagnostic test. All HBsAg positive samples were verified using enzyme-linked immunosorbent assay. RESULTSThe mean age of participants was 26 &plusmn; 6 years. The overall hepatitis HBsAg prevalence was 13.8% with higher rate (22%) reported in women between 30-34 years of age. Majority of HBsAg positive participants were Melanesians (29 out for 33). None of the pregnant women in the 15-19 years and &ge; 40 years tested positive for HBsAg. There was no statistically significant difference in HBsAg prevalence by age, ethnicity, education and residential location. The overall HBeAg seroprevalence was 36.7%. Women between 20-24 years of age had the highest rate of 54.5%. Low level of knowledge about hepatitis B vaccination was reputed. Overall, 54.6% of participants were not aware of their hepatitis B vaccination status and only 65.2% of mothers reported their child had been vaccinated. CONCLUSIONHepatitis B is a disease of public health importance in Solomon Islands and emphasize the need for integrated preventative interventions for its control.

Hepatitis B surface antigen and hepatitis B core-related antigen kinetics after adding pegylated-interferon to nucleos(t)ids analogues in hepatitis B e antigen-negative patients

BACKGROUND Hepatitis B e antigen-negative chronic hepatitis B patients under nucleos(t)ids analogues(NAs)rarely achieve hepatitis B surface antigen(HBsAg)loss.AIM To evaluate if the addition of pegylated interferon(Peg-IFN)could decrease HBsAg and hepatitis B core-related antigen(HBcrAg)levels and increase HBsAg loss rate in patients under NAs therapy.METHODS Prospective,non-randomized,open-label trial evaluating the combination of Peg-IFN 180μg/week plus NAs during forty-eight weeks vs NAs in monotherapy.Hepatitis B e antigen-negative non-cirrhotic chronic hepatitis B patients of a tertiary hospital,under NAs therapy for at least 2 years and with undetectable viral load,were eligible.Patients with hepatitis C virus,hepatitis D virus or human immunodeficiency virus co-infection and liver transplanted patients were excluded.HBsAg and HBcrAg levels(log10 U/mL)were measured at baseline and during ninety-six weeks.HBsAg loss rate was evaluated in both groups.Adverse events were recorded in both groups.The kinetic of HBsAg for each treatment group was evaluated from baseline to weeks 24 and 48 by the slope of the HBsAg decline(log10 IU/mL/week)using a linear regression model.RESULTS Sixty-five patients were enrolled,61%receiving tenofovir and 33%entecavir.Thirty-six(55%)were included in Peg-IFN-NA group and 29(44%)in NA group.After matching by age and treatment duration,baseline HBsAg levels were comparable between groups(3.1 vs 3.2)(P=0.25).HBsAg levels at weeks 24,48 and 96 declined in Peg-IFN-NA group(-0.26,-0.40 and-0.44)and remained stable in NA group(-0.10,-0.10 and-0.10)(P<0.05).The slope of HBsAg decline in Peg-IFN-NA group(-0.02)was higher than in NA group(-0.00)(P=0.015).HBcrAg levels did not change.Eight(22%)patients discontinued Peg-IFN due to adverse events.The HBsAg loss was achieved in 3(8.3%)patients of the Peg-IFN-NA group and 0(0%)of the NA group.CONCLUSION The addition of Peg-IFN to NAs caused a greater and faster decrease of HBsAg levels compared to NA therapy.Side effects of Peg-IFN can limit its use in clinical practice.