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.

Hepatitis B virus infection:defective surface antigen expression and pathogenesis

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.

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.

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.

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.

Expression of hepatitis B virus surface antigen in 120 Hodgkin's lymphoma patients

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.

Significance of hepatitis B virus surface antigen, hepatitis C virus expression in hepatocellular carcinoma and pericarcinomatous tissues

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.

Positive Rate of Different Hepatitis B Virus Serological Markers in Peking Union Medical College Hospital,a General Tertiary Hospital in Beijing

Objectives To investigate the positive rate of different hepatitis B virus （HBV） serological markers, and the demographic factors related to HBV infection. Methods We enrolled all patients tested for HBV serological markers, such as HBV surface antigen （HBsAg）, HBV surface antibody （HBsAb）, hepatitis B e antigen （HBeAg）, hepatitis B e antibody （HBeAb）, HBV core antibody （HBcAb）, and HBV-DNA from July 2008 to July 2009 in Peking Union Medical College Hospital. The positive rate of each HBV serological marker was calculated according to gender, age, and department, respectively. The positive rates of HBV-DNA among patients with positive HBsAg were also analyzed. Results Among 27 409 samples included, 2681 （9.8%） were HBsAg positive. When patients were divided into 9 age groups, the age-specific positive rate of HBsAg was 1.2%, 9.6%, 12.3%, 10.9%, 10.3%, 9.7%, 8.0%, 5.8%, and 4.3%, respectively. The positive rate of HBsAg in non-surgical department, surgical department, and health examination center was 16.2%, 5.8%, and 4.7%, respectively. The positive rate of HBsAg of males （13.3%） was higher than that of females （7.3%, P=0.000）. Among the 2681 HBsAg （＋） patients, 1230 （45.9%） had HBV-DNA test, of whom 564 （45.9%） were positive. Patients with HBsAg （＋）, HBeAg （＋）, and HBcAg （＋） result usually had high positive rate of HBV-DNA results （71.8%, P=0.000）. Conclusions Among this group of patients in our hospital, the positive rate of HBsAg was relatively high. Age group of 20-29, males, and patients in non-surgical departments were factors associated with high positive rate of HBsAg.

Expression of hepatitis B virus surface antigens induces defective gonad phenotypes in Caenorhabditis elegans

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.

The Expression of Sperm Membrane Peptide-Hepatitis B SurfaceAntigen Fusion Protein with Recombinant Vaccinia Virus

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.

Cost effective filamentous phage based immunization nanoparticles displaying a full-length hepatitis B virus surface antigen

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.

Identification and Characterization of Hepatitis B Virus Immune Escape Mutants in Kenya

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.

Diagnostic strategy for occult hepatitis B virus infection

In 2008,the European Association for the study of the liver(EASL) defined occult hepatitis B virus infection (OBI) as the"presence of hepatitis B virus(HBV) DNA in the liver(with detectable or undetectable HBV DNA in the serum) of individuals testing hepatitis B surface antigen(HBsAg) negative by currently available assays".Several aspects of occult HBV infection are still poorly understood,including the definition itself and a standardized approach for laboratory-based detection,which is the purpose of this review.The clinical significance of OBI has not yet been established;however,in terms of public health,the clinical importance arises from the risk of HBV transmission.Consequently,it is important to detect high-risk groups for occult HBV infection to prevent transmission.The main issue is,perhaps,to identify the target population for screening OBI.Viremia is very low or undetectable in occult HBV infection,even when the most sensitive methods are used,and the detection of the viral DNA reservoir in hepatocytes would provide the best evaluation of occult HBV prevalence in a defined set of patients.However,this diagnostic approach is obviously unsuitable:blood detection of occult hepatitis B requires assays of the highest sensitivity and specificity with a lower limit of detection<10 IU/mL for HBV DNA and<0.1 ng/mL for HBsAg.

Hepatitis B and C virus co-infections in human immunodeficiency virus positive North Indian patients

AIM： To determine the prevalence of hepatitis B and C virus infections in human immunodeficiency virus （HIV） -positive patients at a tertiary care hospital in New Delhi, India. METHODS： Serum samples from 451 HIV positive patients were analyzed for HBsAg and HCV antibodies during three years （Jan 2003-Dec 2005）. The control group comprised of apparently healthy bone-marrow and renal donors. RESULTS： The study population comprised essentially of heterosexually transmitted HIV infection. The prevalence Fate of HBsAg in this population was 5.3% as compared to 1.4% in apparently healthy donors （P 〈 0.001）. Though prevalence of HCV co-infection （2.43%） was lower than HBV in this group of HIV positive patients, the prevalence was significantly higher （P 〈 0.05） than controls （0.7%）. Triple infection of HIV, HBV and HCV was not detected in any patient. CONCLUSION： Our study shows a significantly high prevalence of hepatitis virus infections in HIV infected patients. Hepatitis viruses in HIV may lead to faster progression to liver cirrhosis and a higher risk of antiretroviral therapy induced hepatotoxicity. Therefore, it would be advisable to detect hepatitis virus coinfections in these patients at the earliest.

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.

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.

Hepatitis B surface antigen escape mutations: Indications for initiation of antiviral therapy revisited

Approximately 240 million people are chronically infected with hepatitis B. The implementation of rigorous vaccination programs has led to an overall decrease in the prevalence of this disease worldwide but this may also have led to emergence of viral mutations that can escape the protection of hepatitis B surface antibody. As this phenomenon is increasingly recognized, concern for transmission to vaccinated individuals has also been raised. Herein, we describe two cases where the suspected presence of a hepatitis B surface antigen escape mutation impacted the decision to initiate early antiviral therapy, as well as provide a brief review of these mutations. Our findings described here suggest that a lower threshold for initiating therapy in these individuals should be considered in order to reduce the risk of transmission, as vaccination does not provide protection.

Predictors of loss of hepatitis B surface antigen in HIV-infected patients

AIM:To study factors associated with loss of hepatitis B surface antigen (HBsAg) in patients co-infected with human immunodeficiency virus (HIV) and hepatitis B virus (HBV).METHODS:We retrospectively reviewed the medical records of 5681 patients followed up at two New York City HIV clinics from January 1999 to May 2007.Clinical and laboratory parameters including baseline and follow-up HIV viral loads,CD4 cell counts,alanine transaminase levels,demographics,presence of hepatitis C infection,and treatment with highly active antiretroviral therapy dually active against both HIV and HBV infection,were analyzed to determine factors associated with loss of HBsAg.RESULTS:Three hundred and fifty five patients (355/5681,6.84%) were co-infected with HIV and HBV and were evaluated.Of these,226 patients with more than 12 mo follow-up were included in further analysis to determine factors associated with loss of HBsAg in the long-term follow-up.In the univariate analysis,baseline CD4 cell count was associated with loss of HBsAg (P=0.052).Cox regression analysis revealed that loss of HBsAg was associated with baseline CD4 cell count > 500 cells/mm3 (P=0.016,odds ratio:76.174,95% confidence interval:2.233-2598.481).CONCLUSION:Our study showed an interesting association of loss of HBsAg in HIV-HBV co-infected patients with higher CD4 cell count,suggesting that T-cell cytolytic activity against HBV may still be effective in clearing HBV infection.

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.

HBV C基因型有关的HBsAg阴性HBV DNA阳性患者S区突变对HBsAg的影响

目的通过构建HBV C基因型突变质粒研究HBsAg阴性HBV DNA阳性患者HBV S区突变对HBsAg水平的影响。方法收集2022年8月至2023年4月首都医科大学附属北京佑安医院107例HBsAg-/HBV DNA+患者血液样本,对成功提取扩增的HBV DNA S区进行测序,通过构建HBV C基因型突变质粒对HBV S区突变位点进行细胞功能验证,探讨OBI可能发生的分子机制。结果对成功提取扩增的68例患者进行测序,发现HBV S区存在大量突变,包括免疫逃逸突变(如sG145R、sK122R、sS114T、sT131P等)和跨膜结构域(transmembrane domain,TMD)突变(如sT5A、sG10D、sF20S等)。通过构建HBV C基因型突变质粒,进行细胞转染和细胞免疫荧光实验发现sG145R突变会明显降低HBsAg的表达,但是sK122R、sI26N、sQ29N、sR169H、sS114T、sT131P这6个突变位点并未影响细胞内外HBsAg的表达。结论通过测序发现HBsAg-/HBV DNA+患者HBV S区存在大量突变位点,通过构建sG145R、sK122R、sI26N、sQ29N、sS114T和ST131P等突变质粒发现sG145R突变会明显降低细胞内外HBsAg的表达,但是sK122R、sI26N、sQ29N、sR169H、sS114T、sT131P并未明显降低细胞内外HBsAg的表达。