Different pre-S deletion patterns and their association with hepatitis B virus genotypes

AIM To investigate the associations of different types of pre-S deletions with hepatitis B virus(HBV) genotypes.METHODS The sequences of the pre-S region, basal core promoter(BCP) mutation, and precore(PC) mutation were examined through direct DNA sequencing or clonal analysis and sequencing in 273 HBV carriers, namely 55 asymptomatic carriers, 55 carriers with chronic hepatitis(CH), 55 with liver cirrhosis(LC), 53 with liver cirrhotic hepatocellular carcinoma(LC-HCC), and 55 with noncirrhotic HCC. A total of 126 HBV carriers(46.2%) harbored pre-S deletions. The DNA sequences of pre-S deletion mutants from 43 age-matched genotype B(HBV/B)-infected carriers and 43 agematched genotype C(HBV/C)-infected carriers were further examined, aligned, and compared.RESULTS No significant difference was observed in the mean age distribution(P = 0.464), male sex(P = 0.805), viral load(P = 0.635), or BCP mutation(P = 0.117) between the HBV/B and HBV/C groups. However, the rate of PC mutation was significantly higher in the HBV/B-infected carriers than in the HBV/C-infected carriers(P = 0.003). Both genotypes exhibited a high rate of deletion in the C-terminal half of the pre-S1 region and N-terminus of the pre-S2 region(86.0% and 79.1% in the HBV/B group; 69.8% and 72.1% in the HBV/C group, respectively). Epitope mapping showed that deletion in several epitope sites was frequent i n both genotypes, particularly p S1-BT and p S2-B2. Conversely, the rate of p S2-B1 deletion was significantly higher in the HBV/B group(72.1% vs 37.2%, P = 0.002), and the rate of pS 2-T deletion was significantly higher in the HBV/C group(48.8% vs 25.6%, P = 0.044). Functional mapping showed that the rate of deletion in three functional sites(the nucleocapsid binding site, start codon of M, and site for viral secretion) located in the N-terminus of the pre-S2 region was significantly higher in the HBV/B group(P < 0.05). One type of N-terminus pre-S1 deletion mutant with deletion of the start codon of the L protein was frequently observed in the HBV/C group(20.9% vs 9.3%, P = 0.228), particularly in the LC patients(42.9% vs 12.5%). Different patterns of pre-S deletions were also found between the HBV/B and HBV/C groups according to different clinical outcomes. In CH patients, deletion in the site for polymerized human serum albumin was more frequent in the HBV/B group(88.9% vs 36.4%, P = 0.028). In the LC-HCC patients, the rate of deletion in the pre-S2 region was significantly higher in the HBV/B group than in the HBV/C group(P < 0.05).CONCLUSION HBV/B- and HBV/C-infected carriers exhibit different patterns of pre-S deletion, which may be associated with the progression of liver diseases.

Novel approach to identifying the hepatitis B virus pre-S deletions associated with hepatocellular carcinoma

AIM: To develop a novel non-sequencing method for the detection of hepatitis B virus (HBV) pre-S deletion mutants in HBV carriers.

Hepatitis B virus pre-S2 start codon mutations in Indonesian liver disease patients

AIM: To identify the prevalence of pre-S2 start codon mutations and to assess their association with liver disease progression. METHODS: The mutations were identified by direct sequencing from 73 asymptomatic carriers, 66 chronic hepatitis (CH), 66 liver cirrhosis (LC) and 63 hepatocellular carcinoma (HCC) patients. Statistical significances were determined using Fisher's exact test, χ 2 test, and t -test analyses whenever appropriate. Pre-S mutation as a risk factor for advanced liver disease was estimated by unconditional logistic regression model adjusted with age, sex, and hepatitis B e antigen (HBeAg). P < 0.05 was considered significant. RESULTS: Mutation of the hepatitis B virus (HBV) pre-S2 start codon was found in 59 samples from 268 subjects (22.0%), with higher prevalence in patients with cirrhosis 27/66 (40.9%) followed by HCC 18/63 (28.6%), chronic hepatitis 12/66 (18.2%) and asymptomatic carriers 2/73 (2.7%) (P < 0.001). Logistic regression analysis showed that pre-S2 start codon mutation was an independent factor for progressive liver disease. Other mutations, at T130, Q132, and A138, were also associated with LC and HCC, although this was not statistically significant when adjusted for age, sex, and HBeAg. The prevalence of pre-S2 start codon mutation was higher in HBV/B than in HBV/C (23.0% vs 19.1%), whilst the prevalence of T130, Q132, and A138 mutation was higher in HBV/C than in HBV/B. The prevalence of pre-S2 start codon mutation was higher in LC (38.9%) and HCC (40.0%) than CH (5.6%) in HBeAg(+) group, but it was similar between CH, LC and HCC in HBeAg(-) group. CONCLUSION: Pre-S2 start codon mutation was higher in Indonesian patients compared to other Asian countries, and its prevalence was associated with advanced liver disease, particularly in HBeAg(+) patients.

Elevated soluble 4-1BB is associated with serum markers of hepatitis B virus in patients with chronic hepatitis B

BACKGROUND Previous studies have suggested that the costimulatory molecule 4-1BB plays pivotal roles in regulating immunity during chronic viral infection.However,up to now,there are few studies about 4-1BB in chronic hepatitis B(CHB).AIM To clarify this issue,we report our comprehensive study results on the expression levels of 4-1BB in patients with CHB.METHODS From September 2018 to June 2019,a total of 64 patients with CHB were recruited from the Department of Hepatology,The First Hospital of Jilin University.Peripheral blood samples were collected from 52 treatment-naïve and 12 entecavir-treated patients with CHB as well as 37 healthy donors(including 24 healthy adults and 13 healthy children).The levels of soluble 4-1BB(s4-1BB)in plasma were measured by ELISA.4-1BB mRNA expression in peripheral blood mononuclear cells was detected by real-time quantitative PCR.RESULTS The s4-1BB levels in the plasma of patients with CHB were significantly higher than those in healthy adults(94.390±7.393 ng/mL vs 8.875±0.914 ng/mL,P<0.001).In addition,the s4-1BB level in plasma was significantly increased in patients with a higher viral load and a disease flare up.However,there were no significant differences between treatment-naïve and entecavir-treated patients.Interestingly,among treatment-naïve patients with CHB,the levels of s4-1BB in plasma had a significant positive correlation with hepatitis B surface antigen,hepatitis B virus DNA,hepatitis B e antigen,and triglyceride levels(r=0.748,P<0.001;r=0.406,P=0.004;r=0.356,P=0.019 and r=-0.469,P=0.007,respectively).The 4-1BB mRNA expression was higher in the peripheral blood mononuclear cells of patients with CHB than in the peripheral blood mononuclear cells of healthy adults,but the difference was not statistically significant.CONCLUSION These results suggest that the levels of s4-1BB may be associated with pathogenesis of hepatitis B virus and therefore may be a promising biomarker for disease progression.

Hepatitis B virus pre-S/S variants in liver diseases

Chronic hepatitis B is a global health problem. The clinical outcomes of chronic hepatitis B infection include asymptomatic carrier state, chronic hepatitis(CH), liver cirrhosis(LC), and hepatocellular carcinoma(HCC). Because of the spontaneous error rate inherent to viral reverse transcriptase, the hepatitis B virus(HBV) genome evolves during the course of infection under the antiviral pressure of host immunity. The clinical significance of pre-S/S variants has become increasingly recognized in patients with chronic HBV infection. Pre-S/S variants are often identified in hepatitis B carriers with CH, LC, and HCC, which suggests that these naturally occurring pre-S/S variants may contribute to the development of progressive liver damage and hepatocarcinogenesis. This paper reviews the function of the pre-S/S region along with recent findings related to the role of pre-S/S variants in liver diseases. According to the mutation type, five pre-S/S variants have been identified: pre-S deletion, pre-S point mutation, pre-S1 splice variant, C-terminus S point mutation, and pre-S/S nonsense mutation. Their associations with HBV genotype and the possible pathogenesis of pre-S/S variants are discussed. Different pre-S/S variants cause liver diseases through different mechanisms. Most cause the intracellular retention of HBV envelope proteins and induction of endoplasmic reticulum stress, which results in liver diseases. Pre-S/S variants should be routinely determined in HBV carriers to help identify individuals who may be at a high risk of less favorable liver disease progression. Additional investigations are required to explore the molecular mechanisms of the pre-S/S variants involved in the pathogenesis of each stage of liver disease.

Sex disparity in viral load, inflammation and liver damage in transgenic mice carrying full hepatitis B virus genome with the W4P mutation in the preS1 region

AIM To study sex disparity in susceptibility to hepatocellular carcinoma(HCC), we created a transgenic mouse model that expressed the full hepatitis B virus(HBV) genome with the W4P mutation.METHODS Transgenic mice were generated by transferring the p HY92-1.1 x-HBV-full genome plasmid(genotype A2) into C57 Bl/6 N mice. We compared serum levels of hepatitis B surface antigen(HBs Ag), interleukin(IL)-6, and the liver enzymes alanine aminotransferase(ALT) and aspartate transaminase(AST), as well as liver histopathological features in male and female transgenic(W4PTG) mice and in nontransgenic littermates of 10 mo of age. RESULTS W4PTG males exhibited more pronounced hepatomegaly, significantly increased granule generation in liver tissue, elevated HBs Ag expression in the liver and serum, and higher serum ALT and IL-6 levels compared to W4PTG females or littermate control groups. CONCLUSION Together, our data indicate that the W4 P mutation in pre S1 may contribute to sex disparity in susceptibility to HCC by causing increased HBV virion replication and enhanced IL-6-mediated inflammation in male individuals. Additionally, our transgenic mouse model that expresses full HBV genome with the W4 P mutation in pre S1 could be effectively used for the studies of the progression of liver diseases, including HCC.

Antiviral Effect of Interferon-Induced Guanylate Binding Protein-1 against Coxsackie Virus and Hepatitis B Virus B3 in Vitro

Guanylate binding protein-1(GBP-1)is an interferon-induced protein.To observe its antiviral effect against Hepatitis B virus(HBV)and Coxsackie virus B3(CVB3),we constructed an eukaryotic expression vector of human GBP-1(hGBP-1).Full-length encoding sequence of hGBP-1 was amplified by long chain RT-PCR and inserted into a pCR2.1 vector,then subcloned into a pCDNA3.1(-)vector.Recombinant hGBP-1 plasmids and pHBV1.3 carrying 1.3-fold genome of HBV were contransfected into HepG2 cells,and inhibition effect of hGBP-1 against HBV replication was observed.Hela cells transfected with recombinant hGBP-1 plasmids were challenged with CVB3,and viral yield in cultures were detected.The results indicated that recombinant eukaryotic expression plasmid of hGBP-1 was constructed successfully and the hGBP-1 gene carried in this plasmid could be efficiently expressed in HepG2 cells and Hela cells.hGBP-1 inhibit CVB3 but not HBV replication in vitro.These results demonstrate that hGBP-1 mediates an antiviral effect against CVB3 but not HBV and perhaps plays an important role in the interferon-mediated antiviral response against CVB3.

mi R-29a promotes hepatitis B virus replication and expression by targeting SMARCE1 in hepatoma carcinoma

AIM To investigate the functional role and underlying molecular mechanism of mi R-29 a in hepatitis B virus(HBV) expression and replication.METHODS The levels of mi R-29 a and SMARCE1 in HBV-infected Hep G2.2.15 cells were measured by quantitative real-time PCR and western blot analysis. HBV DNA replication was measured by quantitative PCR and Southern blot analysis. The relative levels of hepatitis B surface antigen and hepatitis B e antigen were detected by enzyme-linked immunosorbent assay. The Cell Counting Kit-8(CCK-8) was used to detect the viability of Hep G2.2.15 cells. The relationship between mi R-29 a and SMARCE1 were identified by target prediction and luciferase reporter analysis.RESULTS mi R-29 a promoted HBV replication and expression, w h i le S MA R C E 1 r e p r e s s e d H B V r e p lic a t io n a n d expression. Cell viability detection indicated that mi R-29 a transfection had no adverse effect on the host cells. Moreover, SMARCE1 was identified and validated to be a functional target of mi R-29 a. Furthermore, restored expression of SMARCE1 could relieve the increased HBV replication and expression caused by mi R-29 a overexpression.CONCLUSION mi R-29 a promotes HBV replication and expression through regulating SMARCE1. As a potential regulator of HBV replication and expression, mi R-29 a could be a promising therapeutic target for patients with HBV infection.

Generation of high affinity human single-hain antibody against PreSl of hepatitis B virus from immune phage-display antibody library

BACKGROUND: A single-chain antibody ( ScFv) phage display library was created by cloning antigen-binding re- gions of VH (variable domain) and VL gene repertoires as fusion proteins with a minor coat protein of filamentous phage, from which high affinity completely humanized ScFv against PreS1 of hepatitis B virus could be screened and characterized. METHODS: A combinatorial library of phage-display hu- man ScFv genes, which were derived from peripheral blood lymphocytes immunized by peptide PreS1 in vitro, was constructed. The library contained 7 × 108 clones. RESULTS: After 3 rounds panning, a high affinity (K = 10-7-10-8 mol/L) ScFv specific to PreS1 was obtained. Sequence analysis showed that the VH belonged to the VH4 family and Vλ to Vλ4. CONCLUSIONS: The described ScFv may provide a more satisfactory therapy. This application further illustrates that the method of in vitro antigen stimulation is expeditious for the source of human immune antibody library.

Hydrophobicity of reactive site loop of SCCA1 affects its binding to hepatitis B virus

AIM: To investigate the role of SCCA2 and other SCCA1 molecules in the process of hepatitis B virus (HBV) binding to mammalian cells. METHODS: SCCA1 and SCCA2 were isolated from HepG2. Binding protein (BP) genes were obtained through PCR. Recombinant baculoviruses expressing SCCA1, SCCA2, BP, and different mutants were constructed and utilized to infect mammalian cells to investigate the binding ability of infected cells to HBV. RESULTS: A SCCA1 gene (A1) was isolated from HepG2, but it appeared to lack the binding ability of infected cells to HBV. Two mutants, A1-BP and BP-A1, were constructed by interchanging the carboxyl terminal of A1 and BP. Cells expressing A1-BP showed an increased virus binding capacity, but not BP-A1. Comparison of A1 sequence with the sequence of BP indicated the presence of only three amino acid changes in the carboxyl terminal, two of them were found in the reactive site loop (RSL) of SCCA1. Primary structure assay revealed that the hydrophobicity of BP and AJ515706 in this domain was strong, but A1 was relatively weak. Changing the aa349 of A1 from low hydrophobic glutamic add to high hydrophobic valine enhanced HBV binding. In contrast, HBV binding was reduced by changing the aa349 of BP from valine to glutamic acid. CONCLUSION: The results suggest that the hydrophobicity of RSL of SCCA1 may play an important role in HBV binding to cells.

Study of human B7 homolog 1 expression in patients with hepatitis B virus infection

AIM: To further investigate the role of human B7 homolog 1 (B7-H1) in the mechanism of persistent hepatitis B virus (HBV) infection. METHODS: Peripheral and intra-hepatic B7-H1 expression were compared by flow cytometry and immunochemical staining between two 2 distinct groups, one being chronic HBV tolerance patients (CHB-T) and the other being acute hepatitis B patients (AHB). B7-H1 mRNA expression level was also compared by real time polymerase chain reaction between CHB-T and AHB patients. The location of intra-hepatic B7-H1 and CD40 expression were analyzed by immunofluorescence. The levels of B7-H1 and CD40 expression on cultured myeloid dendritic cells (mDCs) with or without hepatitis B surface antigen (HBsAg) treatment were analyzed dynamically by flow cytometry. Intracellular interferon-γ (IFN-γ) staining and the stimulatory capacity of mDC of cultured mDC with or without HBsAg treatment were also compared by flow cytometry. RESULTS: Peripheral B7-H1 expression on mDCs was increased significantly in AHB compared to CHB-T patients (P < 0.05). In the liver tissues from CHB-T patients, B7-H1 positive cells were almost absent despite a persistently elevated serum HBsAg load. In contrast, there were indeed increased B7-H1-positive cells in situ in the liver tissue from AHB. In vitro analysis showed the parallel upregulation of B7-H1 and CD40 on CD11c+ mDCs after the onset of stimulation. Addition of recombinant hepatitis B surface antigen (rHBsAg) significantly decreased CD40 expression (P < 0.05 at 16 h, 20 h and 24 h time points). B7-H1 expression was also inhibited by rHBsAg, and the inhibition rate of CD40 was greater than that of B7-H1. This preferential inhibition of CD40 expression on mDCs by rHBsAg resulted in the dysfunction of mDCs and T cells in the mixed leucocyte reaction (MLR) system. With rHBsAg pretreatment, in a carboxyfluorescein diacetate succinimidyl ester (CFSE) labeled MLR system at a ratio of 1:5 responder cell-stimulator cell (R/S), the CFSE dim percentage of T cells decreased from 85.1% to 25.4% and decreased from 30.3% to 12.0% at 1:10 R/S. IFN-γ production by CD8+ T cells, in the MLR system, was reduced significantly by HBsAg pretreatment. At ratios of 1:5 R/S, the percentage of IFN-γ and CD8 dual positive T cells decreased from 55.2% ± 5.3% to 15.1% ±3.1% (P < 0.001), and decreased from 35.0% ± 5.1% to 7.3% ± 2.7% at ratios of 1:10 R/S (P < 0.001). CONCLUSION: B7-H1 is not a signature of immune dysfunction, but an inflammation marker. HBsAg regulate immune response by tipping the balance between B7-H1 and CD40.

Cloning and expression of the preS1 gene of hepatitis B virus in yeast cells

Objective: To investigate the complex functions of HBV preS1 protein, we constructed HBV preS1 gene expression vector and expressed it in yeast cells. Methods: Polymerase chain reaction (PCR) was per- formed to amplify the gene of HBV preS1 from the plasmid pCP10 containing the whole DNA fragment of HBV ayw subtype as template and the PCR prod- uct was cloned into the pGEM-T vector for sequen- cing. After being identified, the HBV preSl gene was cut from the pGEM-T vector by EcoR I and Pst I restriction enzymes, and cloned into yeast expres- sive plasmid pGBKT7 to constructe pGBKT7-preS1 recombinant expressive plasmid. This plasmid was transformed into yeast cell AH109 and expressed in it. The yeast protein was isolated and analyzed with sodium dodecyl suifate-polyacrylamide gel electro- phoresis(SDS-PAGE) and Western blotting. Results: The HBV preS1 gene was amplified success- fully and identified by DNA sequencing. The PCR products were coincided completely with the reported sequence. The digested fragments were cloned into the pGBKT7 vector and transformed into yeast cell AH109. The results of SDS-PAGE and Western blot- ting assay showed: (1) The HBV preS1 protein was expressed and existed in yeast cells; (2) The molecu- lar weight of the expression product was about 30 000 D. Conclusion: The HBV preS1 gene was successfully cloned and expressed in yeast cells.

Immunomodulatory effects of Tim-3 and PD-1 on chronic hepatitis B virus infection

In patients with chronic hepatitis B virus(HBV) infection, the immune cells are dysfunctional, and the immune function cannot work normally. T-cell immunoglobulin mucin-3(Tim-3) and programmed death receptor-1(PD-1) are overexpressed on the surface of immune cells, such as cluster of differentiation(CD)4+, CD8+ T-lymphocytes, and natural killer(NK) cells. Many studies indicate that this phenomenon is closely related to the persistence, occurrence, development, and prognosis of HBV. Tim-3 and PD-1 may be used as new immune targets for the treatment of chronic hepatitis B.

Potential mechanisms of hepatitis B virus induced liver injury

Chronic active hepatitis(CAH) is acknowledged as an imperative risk factor for the development of liver injury and hepatocellular carcinoma.The histological end points of CAH are chronic inflammation,fibrosis and cirrhosis which are coupled with increased DNA synthesis in cirrhotic vs healthy normal livers.The potential mechanism involved in CAH includes a combination of processes leading to liver cell necrosis,inflammation and cytokine production and liver scaring(fibrosis).The severity of liver damage is regulated by Hepatitis B virus genotypes and viral components.The viral and cellular factors that contribute to liver injury are discussed in this article.Liver injury caused by the viral infection affects many cellular processes such as cell signaling,apoptosis,transcription,DNA repair which in turn induce radical effects on cell survival,growth,transformation and maintenance.The consequence of such perturbations is resulted in the alteration of bile secretion,gluconeogenesis,glycolysis,detoxification and metabolism of carbohydrates,proteins,fat and balance of nutrients.The identification and elucidation of the molecular pathways perturbed by the viral proteins are important in order to design effective strategy to minimize and/or restore the hepatocytes injury.

Screening and cloning for proteins transactivated by the PS1TP5 protein of hepatitis B virus:A suppression subtractive hybridization study

AIM： To clone and identify human genes transactivated by PSITP5 by constructing a cDNA subtractive library with suppression subtractive hybridization （SSH） technique. METHODS： SSH and bioinformatics techniques were used for screening and cloning of the target genes transactivated by PS1TP5 protein. The mRNA was isolated from HepG2 cells transfected with pcDNA3.1（-）- myc-his（A）-PS1TP5 and pcDNA3.1（-）-myc-his（A） empty vector, respectively, and SSH technique was employed to analyze the differentially expressed DNA sequence between the two groups. After digestion with restriction enzyme Rsa Ⅰ, small size cDNAs were obtained. Then tester cDNA was divided into two groups and ligated to the specific adaptor 1 and adaptor 2, respectively. The tester cDNA was hybridized with driver cDNA twice and subjected to nested PCR for two times, and then subcloned into T/A plasmid vectors to set up the subb-active library. Amplification of the library was carried out with E.. coil strain DH5α. The cDNA was sequenced and analyzed in GenBank with Vector NTI 9.1 and NCBI BLAST software after PCR amplification. RESULTS： The subtractive library of genes transactivated by PS1TP5 was constructed successfully. The amplified library contained 90 positive clones. Colony PCR showed that 70 clones contained 200-1000-bp inserts. Sequence analysis was performed in 30 clones randomly, and the full-length sequences were obtained by bioinformatics technique. Altogether 24 coding sequences were obtained, which consisted of 23 known and 1 unknown.One novel gene with unknown functions was found and named as PSITP5TP1 after being electronically spliced, and deposited in GenBank （accession number： DQ487761）. CONCLUSION： PSITP5 is closely correlated with immunoregulation, carbohydrate metabolism, signal transduction, formation mechanism of hepatic fibrosis, and occurrence and development of tumor. Understanding PSlTP5 transactive proteins may help to bring some new clues for further studying the biological functions of pre-S1 protein.

Expression of co-stimulatory molecules B7-2 and PD-L1 on peripheral blood mononuclear cells in patients with chronic hepatitis B virus infection

Objective： To explore the roles of the expression of the co-stimulatory molecule, B7-2, and the co-inhibitory molecule, PD-L1, on peripheral blood mononuclear cells in the mechanism of immunotolerance in chronic hepatitis B virus infection. Methods： Thirty HBV infected patients in the immunoreactive phase and 20 patients in the immunotolerant phase were enrolled in the study, while 20 healthy volunteers were used as controls. RT- PCR and real-time PCR methods were used to detect the expression levels of B7-2 and PD-L1 mRNA in peripheral blood mononuclear cells in chronic HBV infected patients. Results： The B7-2 expression in irnrnunoreactive and immunotolerant patients was significantly lower than that in the controls （P all 〈 0.01 ）; B7-2 expression in immunoreactive patients was significantly lower than in immunotolerant patients （P 〈 0.01）. PD-L1 expression in irnmunoreactive patients and immunotolerant patients was significantly higher than that in normal controls （P all 〈 0.01）. The PD-L1/BT-2 ratios in immunoreactive and immunotolerant patients were significantly higher than that of the healthy controls （P all 〈 0.01）; the PD-L1/ B7-2 ratio was significantly higher in the immunoreactive patients than in the immunotolerant patients （P 〈 0.01）. Conclusion： In chronic HBV infection, changes in the expression of co-stimulatory and co-inhibitory molecules imply a protective adjustment against the patient＇ s immune response that may result in increased immunotolerance and persistent HBV infection.

HMGB1 gene polymorphisms in patients with chronic hepatitis B virus infection

AIM: To characterize high mobility group box chromosomal protein 1(HMGB1) polymorphisms in patients infected with hepatitis B virus(HBV) and determine the different patterns in patient subgroups.METHODS: A total of 1495 unrelated Han Chinese HBV carriers were recruited in this hospital-based casecontrol study.The HMGB1 1176 G/C polymorphism was genotyped by polymerase chain reaction-restriction fragment length polymorphism assay.RESULTS: A significant association was observed between HMGB1 1176 G/C polymorphism and outcome of HBV infection.The subjects bearing 1176G/G genotype had an increased risk of susceptibility to chronic hepatitis B,liver cirrhosis and severe hepatitis B when compared with those bearing at least one 1176C allele.CONCLUSION: Patients with 1176G/G genotype of HMGB1 gene are more likely to have a progressive status in HBV infection.

Th1/Th2 cytokines and their genotypes as predictors of hepatitis B virus related hepatocellular carcinoma

Hepatocellular carcinoma(HCC), the predominant type of primary liver cancer, is one of the most serious lifethreatening malignancies, worldwide. In majority of the cases, HCC develops after prolonged and persistent chronic liver disease. hepatitis B virus(HBV) or HCV infection is prominent etiological factors, attributing to this condition. It has been well documented that HBV, being the inducer of chronic inflammation, is the main causative agent in causing HCC, particularly in Asian countries. The HBV infection leads to a wide range of clinical symptoms from carrier state to malignancy. Cytokines being immune-modulatory molecules, are the key mediators in the defense mechanism against viral infection. In this regard, this review will detail the substantial role of key Th1: interleukin 1(IL-1), IL-2, IL-12, tumor necrosis factor-α, interferon-γ; Th2: IL-4, IL-10 and non Th1/Th2: IL-6, transforming growth factor-β1 cytokines genotypes in analyzing the variability in the clinical manifestations in an HBV-afflicted individual, which might finally, culminates into HCC. Since cytokine production is regulated genetically, the cytokine promoter region single-nucleotide polymorphisms induced changes, greatly affects the cytokine production, thus resulting into differential outcome of immune balance.

Clinical features of HBs Ag seroclearance in hepatitis B virus carriers in South Korea: A retrospective longitudinal study

AIM To investigate the characteristic features of hepatitis B surface antigen(HBs Ag) seroclearance among Korean hepatitis B virus(HBV) carriers.METHODS Carriers with HBs Ag seroclearance were selected by analyzing longitudinal data collected from 2003 to 2015. The period of time from enrollment to the negative conversion of HBs Ag(HBs Ag-NC) was compared by stratifying various factors, including age, sex, hepatitis B e antigen(HBe Ag), HBV DNA, sequential changes in the signal-to-cutoff ratio of HBs Ag(HBs Ag-SCR), as measured by qualitative HBs Ag assay, and chronic liver disease on ultrasonography(US-CLD). Quantification of HBV DNA and HBs Ag(HBs Ag-QNT) in the serum was performed by commercial assay.RESULTS Among the 1919 carriers, 90(4.7%) exhibited HBs AgNC at 6.2 ± 3.6 years after registration, with no differences observed among the different age groups. Among these carriers, the percentages of those with asymptomatic liver cirrhosis(LC) and hepatocellular carcinoma(HCC) at registration were 31% and 7.8%, respectively. The frequency of HBs Ag-NC significantly differed according to the HBV DNA titer and US-CLD. HBe Ag influenced HBs Ag-NC in the 40-50 and 50-60 year age groups. HBs Ag-SCR < 1000 was correlated with an HBs Ag-QNT < 200 IU/m L. A gradual decrease in the HBs Ag-SCR to < 1000 predicted HBs Ag-NC. Six patients developed HCC after registration, including two before and four after HBs Ag-NC. The rate at which the patients developed new HCC after HBs Ag seroclearance was 4.8%. LC with excessive drinking and vertical infection were found to be risk factors for HCC in the HBs Ag-NC group.CONCLUSION HCC surveillance should be continued after HBs Ag seroclearance. An HBs Ag-SCR < 1000 and its decrease in sequential testing are worth noting as predictive markers of HBs Ag loss.

Hepatitis B virus pre S1 deletion is related to viral replication increase and disease progression

AIM:To investigate the clinical implications of hepatitis B virus(HBV) pre S1 deletion.METHODS:We developed a fluorescence resonance energy transfer-based real-time polymerase chain reaction(RT-PCR) that can detect four genotypes(wild type, 15-bp, 18-bp and 21-bp deletion).The PCR method was used in two cohorts of Korean chronic HBV subjects with genotype C infections.Cohort Ⅰ included 292 chronic HBV subjects randomly selected from Cheju National University Hospital(Jeju, South Korea) or Seoul National University Hospital(Seoul, South Korea), and cohort Ⅱ included 90 consecutive chronic HBV carriers recruited from Konkuk University Hospital(Seoul, South Korea); the cohort Ⅱ patients did not have hepatocellular carcinoma or liver cirrhosis.RESULTS:The method proposed in this study identified 341 of 382 samples(89.3%).Deletion variants were identified in 100(29.3%) of the 341 detected samples.In both cohorts, the subjects with deletions had a significantly higher Hepatitis B virus e antigen(HBe Ag)-positive seroprevalence [cohort Ⅰ, wild(51.0%) vs deletion(75.0%), P < 0.001; cohort Ⅱ, wild(69.2%) vs deletion(92.9%), P = 0.002] and higher HBV DNA levels [cohort Ⅰ, wild(797.7 pg/m L) vs deletion(1678.9 pg/m L), P = 0.013; cohort Ⅱ, wild(8.3 × 108 copies/m L) vs deletion(2.2 × 109 copies/m L), P = 0.049], compared to subjects with wild type HBV.CONCLUSION:HBV genotype C pre S1 deletion may affect disease progression in chronic HBV subjects through an extended duration of HBe Ag seropositive status and increased HBV replications.