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【Objective】 To evaluate the role of anti-HBc detection in current blood screening strategy by the follow-up of repeated donors with antibody to hepatitis B virus core antigen. 【Methods】 Plasma samples were collected randomly from Dalian Blood Center. to test anti-HBc(dual reagents) and anti-HBs via ELISA. The re-donation of eligible donors who were anti-HBc+ and donors reactive to HBV detection were followed up. 【Results】 A total of 1 291 plasma samples were collected randomly from May 2017 to March 2018, among which 405 samples(31.4%)were anti-HBc+. The median age of anti-HBc+ group was observed much higher than that of anti-HBc-group (39 vs 31 years old) (P0.05). Among the 405 anti-HBc+ donors, 3 donors were OBI (0.7%), of which one was screened out in second donation. No HBV DNA was detected out in 3 OBI cases. 【Conclusion】 Although anti-HBc detection is not suitable in blood screening currently, it is of great value in the assessment of blood donor re-entry for HBV reactive donors in blood screening due to the high anti-HBc prevalence among blood donors.
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ABSTRACT BACKGROUND: Occult hepatitis B virus infection (OBI) is defined as the presence of hepatitis B virus (HBV) deoxyribonucleic acid (DNA) in the liver of individuals with undetectable hepatitis B virus surface antigen (HBsAg) in the serum. The actual prevalence of OBI and its clinical relevance are not yet fully understood. OBJECTIVE: To evaluate the prevalence of HBV DNA in liver biopsies of HBsAg-negative patients with chronic liver disease of different etiologies in a referral center in Brazil and compare two different HBV DNA amplification protocols to detect HBV. DESIGN AND SETTING: This cross-sectional observational study was conducted at the Liver Outpatient Clinic, Hospital das Clínicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil, between January 2016 and December 2019. METHODS: HBV DNA was investigated in 104 liver biopsy samples from individuals with chronic liver disease of different etiologies, in whom HBsAg was undetectable in serum by nested-polymerase chain reaction (nested-PCR), using two different protocols. RESULTS: OBI, diagnosed by detecting HBV DNA using both protocols, was detected in 6.7% of the 104 individuals investigated. Both protocols showed a good reliability. CONCLUSION: In addition to the differences in the prevalence of HBV infection in different regions, variations in the polymerase chain reaction technique used for HBV DNA amplification may be responsible for the large variations in the prevalence of OBI identified in different studies. There is a need for better standardization of the diagnostic methods used to diagnose this entity.
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【Objective】 To analyze the characteristics of gene mutation in S region of blood donors with occult hepatitis B virus infection (OBI) in Huzhou area. 【Methods】 A total of 60 107 blood samples in Huzhou between October 2018 and June 2020 were collected by our blood station. Among them, 52 samples were NAT, yield and their epidemiological characteristics were analyzed. Twenty-seven OBI out of the 52 NAT yield samples were included in experimental group. Other eight HBV-infected individuals with positive HBsAg, core antibody (anti-HBc) and HBV-DNA were selected as positive control. Liver function and 5 serological markers of HBV were compared between the two groups, and HBV genotypes and amino acid mutation in S region in the two groups were analyzed. 【Results】 The number of NAT-yield samples were different by gender, age, and educational background (P0.05). Surface antigen (HBsAg) in the experimental group was significantly lower than that in the control group, while surface antibody (anti-HBs) and e antibody (anti-HBe) were significantly higher than those in the control group (P<0.05). Twenty sequences in S region were obtained from the experimental group, including 4 in S region and 16 in preSS region; 16 cases with type C and 4 cases with type B. 【Conclusion】 The follow-up of NAT-yield blood donors in Huzhou area should be conducted. Compared with HBV infected individuals with positive HBsAg, anti-HBc and HBV-DNA, those with OBI have a higher gene mutation rate in S region.
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【Objective】 To study the level of occult hepatitis B virus methylation and replication related genes, and to explore the effect of the former on the latter. 【Methods】 The cases in control group (healthy control, n=3), occult hepatitis B group (occult HBV group, n=3) and hepatitis B group (HBV group, n=3) were detected by Illumina methylation 850k chip. The difference analysis, GO analysis and KEGG analysis were carried out. The methylation and virus replication related genes DNMT1, DNMT2, Dnmt3a and ZHX2 were screened for RT-PCR. 【Results】 The methylation level of occult HBV group and HBV group was significantly higher than that of the control group. Difference analysis showed that there were 1 050 differential methylation sites in occult HBV group with the methylation level greater than non-methylation level, and 1 340 differential methylation sites as the opposite compared with the control group. In HBV group, there were 1 008 differential methylation sites with methylation level greater than non-methylation level, and 1 242 differential methylation sites as the opposite. Go analysis showed that compared with the control group, the differential gene expression in occult HBV group and HBV group was significantly related to many anabolic processes in biological process (BP), cell composition (CC) and molecular function (MF). The enrichment analysis of KEGG pathway between the control group and the occult HBV group showed that the differential genes were mainly involved in adhesion junction, basal cell carcinoma, endometrial carcinoma, EB virus infection, hepatocellular carcinoma and other signal pathways. The enrichment analysis of KEGG pathway in occult HBV group and HBV group showed that the differential genes were mainly involved in AMPK signal pathway, cell cycle, endometrial cancer, hepatitis C, hepatocellular carcinoma and other signal pathways. DNMT1 and DNMT3a in occult HBV group and HBV group were significantly higher while ZHX2 was significantly lower than those in control group. 【Conclusion】 The methylation level of occult HBV group and HBV group increased significantly while ZHX2 decreased significantly. Hypermethylation inhibited the expression of ZHX2 and changed the replication of hepatitis B virus. Hepatitis B virus DNA methylation provides a theoretical basis for the replication mechanism of hepatitis B virus and a new method for the treatment of hepatitis B virus.
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【Objective】 To investigate the prognosis of blood donors with occult hepatitis B virus infection (OBI) by long-term follow-up and repeated testing of HBsAg and HBV DNA. 【Methods】 From January 1, 2010 to December 31, 2020, voluntary blood donors were screened by both serological and viral nucleic acid(NAT) testing, then samples were further confirmed as HBV DNA positive by manual nested-PCR amplification.A total of 306 cases were detected as HBsAg negative /HBV DNA positive, then followed-up for a long time and re-examined of HBsAg and HBV DNA to confirm whether they had infected with OBI.The prognosis of patients with OBI who experienced long-term immunization was determined by repeated testing. 【Results】 A total of 306 HBsAg negative/ HBV DNA positive blood donors had been followed up, and 40(13.07%, 40/306) were recalled frequently for re-examination.Among them, 90%(36/40), 57.5%(23/40), 40% (16/40)were anti-HBc + , anti-HBs + and anti-HBe + , respectively, and 50%(20/40), 40%(16/40), 7.5%(3/40) and 2.5% (1/40)were anti-HBs+ / anti-HBc + , anti-HBc + / anti-HBs -, anti-HBc -/ anti-HBs + and anti-HBc -/ anti-HBs -, respectively.Those 40 blood donors were followed-up for 1-13 times, with the duration of 8-108 months (0.6~9 years).1 donor (2.5%) was followed-up less than 1 year, 11 (27.5%)>1 year and ≤3 years, 23 (57.5%) 23(57.5%)>3 years and ≤5 years, and 5 (12.5%) for more than 5 years.After long-term following up and repeated testing, 50%(20/40)of OBI blood donors turned negative for HBV DNA (HBsAg negative / HBV DNA negative), 42.5% (17/40)were confirmed as OBI infection (HBsAg negative / HBV DNA positive), and 7.5%(3/40) were hard to determine (after repeated testing, the results were either positive or negative). 【Conclusion】 After long-term following up and repeated screening, we found that none of the OBI patients turned into acute or chronic HBV infection, and most of them maintained OBI.However, OBI blood donors carry very low load of HBV DNA for a long time, which could lead to false negative results of NAT and bring a great challenge to the safety of blood transfusion.
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【Objective】 To investigate the HBV infection of TMA initially reactive but discriminatory test non-reactive samples(NDR) after the individual donation nucleic acid detection(ID-NAT)of TMA, and analyze its serological and molecular biological characteristics, so as to improve the safety of blood transfusion. 【Methods】 121 970 samples of blood donors in the center from January 1, 2021 to December 31, 2021 were routinely tested by serology and nucleic acid of ID NAT, and 21 HBsAg(-)/ NDR samples were random collected. After the plasma samples were concentrated by ultra-high speed centrifugation, the gene sequences of BCP/PC, pre-S/S and S region were amplified by Nested PCR. The S region sequence was also sequenced to analyze the viral genotype and amino acid variation. At the same time, the original TMA retest discriminatory test was adopted, and Roche MPX 2.0 was used for ID-NAT, and the samples was not virus-concentrated.NDR samples were supplemented with electrochemiluminescence for anti-HBc and anti-HBs quantitative detection. 【Results】 Of the 121 970 samples screened, 117(0.096%) were found to be HBsAg(-)/NDR samples, of which 21 samples underwent a confirmation test. Sixteen(76.2%) cases were positive for HBV DNA by TMA retest, 7(33.3%) positive for HBV DNA by Roche MPX 2.0 ID-NAT, 9(42.9%) confirmed by Nested PCR, and 8(38.1%) positive by any two methods. Test results of serological markers were as follows: 17(80.9%) positive anti-HBc and 8(38.1%) positive anti-HBs. Eight infected cases were confirmed to have occult hepatitis B infection(OBI). The gene sequence of S region was successfully amplified and sequenced in 3 cases, all of which belonged to C type. Two mutations occurred in specimen S-2, all of which were outside MHR. There were 13 mutations in sample S-6, 6 mutations outside MHR and 7 mutations inside MHR. 【Conclusion】 Nearly 40% of NDR samples can still be detected as HBV DNA positive after virus concentration. Anti-HBc has a high detection rate, and there may be a potential risk of HBV transmission. The current NAT detection sensitivity should be improved. The amino acid mutation of S gene sequence may be related to OBI formation.
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ABSTRACT The goal of this study was to investigate the prevalence of occult HBV infection in a reference center for the Northern Brazil from 2005 to 2015 and to identify mutations associated with occult hepatitis B. Molecular analysis was performed on 110 serum samples in which anti-HBc was the only positive serological marker. Regions of the HBV genome were amplified by polymerase chain reaction to detect HBV DNA. A prevalence of 4.1% (793/18,889) for anti-HBc alone was identified. Molecular analysis revealed a prevalence of occult HBV infection of 0.04%. HBV DNA detected were identified in individuals who underwent hemodialysis, infected with the hepatitis C virus and from area of high endemicity for HBV. Direct DNA nucleotide sequencing and phylogenetic analysis identified that genotypes A and D and mutations E164D, I195M, P217L and P120S were associated with occult HBV infection in the S gene. This study contributed with epidemiological and molecular information on Northern Brazil samples with a suggestive profile of occult HBV infection in addition to reinforcing the importanceof molecular diagnosis in this type of infection.
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We aimed to emphasise the role of screening beyond conventional serological markers (HBsAg and Anti HCV antibodies for chronic viral hepatitis B and C respectively) in patients with cirrhosis. Patients with cirrhosis of liver are often labelled as having cryptogenic cirrhosis (CC), if no etiology is found. In chronic viral hepatitis B and C (CHB and CHC) induced cirrhosis, HBsAg and Anti HCV antibodies respectively are usually done to rule out the viral infections however their absence have been documented in subset of patients having these infections. In this regard, we hereby present a case labelled as CC and developed HCC; later on, further evaluation turned out to be having both CHB and CHC. A 51-year-old male with diabetes presented with index episode of hemetemesis. On further evaluation he was diagnosed to have cirrhosis of liver. No etiology was found and he was labeled as cirrhosis secondary to Non-alcoholic steatohepatitis (NASH)/cryptogenic cirrhosis. Later on, he developed hepatocellular carcinoma (HCC). We evaluated the patient with HBV DNA and HCV RNA levels keeping possibility of occult hepatitis B (OBI)/ seronegative hepatitis C infection despite HBsAg and Anti HCV antibodies being negative. Both levels were found to be raised and we attributed cirrhosis to dual hit by CHB and CHC. Patient was managed with antiviral drugs successfully with no recurrence of HCC and control of blood sugar levels. We hereby stress that screening beyond the HBsAg and Anti HCV antibodies should be done in all cases of liver cirrhosis in which etiology is not found on initial screening.
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Abstract INTRODUCTION: HBV and HIV have identical transmission routes. The aim of this study was to determine the prevalence of HBV in HIV patients and to detect the presence of occult HBV infection. METHODS: All samples were tested for serology markers and using qPCR. RESULTS: This study included 232 individuals, out of which 36.6% presented with HBV markers and 11.8% presented with HBsAg or HBV-DNA, including 3 patients that showed OBI. CONCLUSIONS: We observed a high prevalence of HBV among HIV patients. In addition, the results suggest that OBI can occur in patients with serological profiles that are indicative of past infection. Therefore, the application of molecular tests may enable the identification of infections that are not evident solely based on serology.
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Humans , HIV Infections/epidemiology , Hepatitis B virus/immunology , Hepatitis B/epidemiology , Hepatitis B Antibodies/blood , Hepatitis B Core Antigens/blood , Hepatitis B Surface Antigens/blood , Brazil/epidemiology , DNA, Viral/blood , HIV Infections/complications , Prevalence , Real-Time Polymerase Chain Reaction , Hepatitis B/complications , Hepatitis B/diagnosisABSTRACT
BACKGROUND Occult hepatitis B virus (HBV) - characterized by the absence of detectable HBsAg in the presence of HBV DNA - represents a potential threat for blood safety. OBJECTIVES This study was conducted with the aim to investigate the serological and molecular characterization of occult HBV infection (OBI) among blood donors in Mozambique. METHODS 1,502 blood donors were tested for HBsAg. All HBsAg-negative individuals were tested for HBV DNA. Antibodies against HBV core, surface and HBe antigen (anti-HBc, anti-HBs, HBeAg) were measured in HBV DNA positive individuals. FINDINGS 1435 serum samples were HBsAg negative and 16 positive for HBV DNA, 14 confirmed to have OBI, corresponding to a frequency of 0.98%. Of the 14 OBI infections identified, 13/14 (92.8%) were positive for anti-HBc, 4/14 (28.5%) for anti-HBs, and no samples were reactive for HBeAg. Of the 14 OBI cases, nine samples (64.2%) were sequenced for the S/P region. Eight samples (88.9%) belonged to genotype A1 and one (11.1%) to genotype E. One escape mutation (T123A) associated with OBI and various amino acid substitutions for genotype A1 and E were observed. MAIN CONCLUSIONS Our results show the importance of using nucleic acid amplification test to detect occult hepatitis B infection in blood donors in Mozambique.
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Humans , Male , Female , Adult , Blood Donors , Hepatitis B virus/isolation & purification , Hepatitis B virus/genetics , Nucleic Acid Amplification Techniques/methods , Hepatitis B/diagnosis , Hepatitis B Surface Antigens/genetics , Phylogeny , DNA, Viral , Polymerase Chain Reaction , Cross-Sectional Studies , MozambiqueABSTRACT
The increasing number of patients on the Singapore national liver transplant waiting list and the lack of donor livers have necessitated a review of the limited use of marginal donor liver grafts. Some grafts are of good quality but are considered marginal due to positive donor antibody to hepatitis B virus core protein serology, and negative hepatitis B surface antigen (HBsAg) and hepatitis B DNA. The fear is of viral reactivation during periods of intense immunosuppression. This is made possible by the ability of the hepatitis B virion to reside in a dormant state within the hepatocyte nucleus despite HBsAg clearance, i.e. the occult hepatitis B infection (OBI). In truth, appropriate selection of recipients and effective post-transplantation immunoprophylaxis significantly reduce the risk of hepatitis B viral reactivation. This article explains the confusion surrounding OBI and reviews current recommendations on how to manage such donor liver grafts.
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Occult hepatitis B infection (OBI) is a cause of concern while screening the blood donors to prevent transfusion-related transmission of infection. This study was conducted to assess the prevalence of OBI using total anti-HBc by ELISA and DNA detection by real time polymerase chain reaction (PCR). The samples included were negative for HBs Ag by ELISA. Out of 1102 samples tested, 156 were positive for total anti-hepatitis B core antigen and 52/156 by real-time PCR. Overall, the prevalence was found to be 4.71% (52/1102). The results indicate that nucleic acid-based testing should be an essential part of screening procedure to prevent missing of OBI.
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In occult hepatitis B infection (OBI), hepatitis B virus DNA (HBV DNA) can be detected in serum samples; however, oral fluid collection for detection of HBV DNA has not yet been explored, despite the availability of collection devices. Serum and oral fluid samples from 45 hepatitis B core antibody (anti-HBc)-positive patients were collected for the amplification of the HBV polymerase gene. HBV DNA was detected in five serum and four oral fluid samples (the detection limit for oral fluid was 1.656 log IU/mL in paired serum). In conclusion, simple methodologies of sample collection and in-house polymerase chain reaction (PCR) allowed detection of HBV DNA, and these could be used to improve the diagnosis of OBI, especially in locations with limited resources.
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Humans , Male , Female , Adult , Aged , Saliva/virology , DNA, Viral/analysis , Hepatitis B/diagnosis , Hepatitis B Antibodies/analysis , Hepatitis B Surface Antigens/analysis , DNA, Viral/blood , Hepatitis B virus/isolation & purification , Hepatitis B virus/genetics , Polymerase Chain Reaction , Viral Load , Middle AgedABSTRACT
Objective@#To analyze the residual risk of transfusion transmitted hepatitis B virus (HBV) infection by enzyme-linked immunosorbent assay (ELISA) method in hepatitis B surface antigen (HBsAg) negative blood donors, and to assess the infection status.@*Methods@#A total of 45551 samples were collected from blood donors.All samples were tested by 2 different ELISA kids of HBsAg and nucleic acid testing (NAT) individually of hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV). Those ELISA HBsAg negative and NAT single reactive (HBsAg-/HBV DNA+ ) specimens were analyzed by quantitative detection of HBV DNA and by serologic testing of HBV antigen and antibody.@*Results@#A total of 44 HBsAg-/HBV DNA+ samples were detected, including 42 occult HBV infections (OBI) and 2 window period infections (WP). The detection rate of OBI rate was 0.90‰, and 32 samples of OBI sample HBV DNA was less than 20 IU/ml, and the OBI detection rate was significantly different between different genders, ages and blood donation times (P<0.05). In the OBI sample, there were 6 serological models, 92.9%(39/42) OBI samples hepatitis B core antibody (HBcAb) positive, and 76.9%(30/39) HBV DNA in HBcAb positive samples were less than 20 IU/ml; 29.5% (13/42) of OBI blood donors hepatitis B e antigen (HBeAb) and HBcAb were also positive, of whom 84.6% (11/13) were HBV DNA quantitatively <20 IU/ml.@*Conclusions@#HBV residual risk of transfusion-transmitted infection may occur through HBsAg- and single NAT reactive blood donors, mainly include OBI, and HBV DNA low level. Blocking of single NAT reactive blood donors could reduce transfusion-transmitted HBV infection.
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The level of viral DNA in patients with occult hepatitis B virus infection (OBI) is very low, and it is difficult to detect the conventional serum marker-HBsAg. OBI brought challenges to the clinical diagnosis and treatment and blood transfusion safety. The mechanism involved in OBI and the clinical implication are getting more and more attention. OBI has a complex mechanism that may involve host factors, the virus itself, and other viral or nonviral factors. OBI has the risk of HBV transmission. HBV can be reactivated and the liver disease can be aggravated in patients with OBI.
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BACKGROUND Many studies have identified mutations in the hepatitis B surface antigen (HBsAg) as important factors limiting the ability of commercial serological assays to detect this viral antigen. However, an association between mutations in the HBsAg gene and the occurrence of occult HBV infection (OBI) in patients has not been established. OBJECTIVES To detect hepatitis B virus (HBV) DNA in patients with anti-HBc as a unique serological marker, a previously published, cost-effective TaqMan-based real-time polymerase chain reaction (PCR) test with minor groove binding probes was adapted for use in this study. The current study also aimed to investigate HBsAg mutations and genotypes of HBV in OBI at the Viral Hepatitis Ambulatory Clinic in Rio de Janeiro to determine any possible association. METHODS Intra-assay and inter-assay reproducibility were determined, and the mean coefficient of variation values obtained were 2.07 and 3.5, respectively. Probit analysis indicated that the 95% detection level was 25 IU/mL. The prevalence of OBI was investigated in 35 serum samples with an ‘anti-HBc alone’ profile from individuals who attended our clinic between 2011 and 2013. FINDINGS HBV DNA was detected in only one sample, resulting in an OBI rate of 2.9%. Nucleotide sequencing of the pre-S/S region was performed to genotype and analyse mutations within the HBsAg gene of this HBV DNA. The HBV in the OBI case was classified as sub-genotype A1, and a sequence analysis of the small S gene revealed 12 mutations in the major hydrophilic region compared to the consensus A1 sequence. Most of these mutations occurred in amino acid residues that have been reported as clinically relevant because they have been implicated in vaccine escape and/or inability to detect HBsAg by commercial serological assays. MAIN CONCLUSIONS Our study suggests the importance of specific HBsAg mutations, different from those in D, B, and C genotypes, in sub-genotype A1 HBV associated with OBI.
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DNA, Viral/isolation & purification , DNA, Viral/genetics , Hepatitis B/genetics , Hepatitis B/virology , Hepatitis B Surface Antigens/genetics , Sensitivity and Specificity , Real-Time Polymerase Chain ReactionABSTRACT
Occult hepatitis B virus infection is a worldwide public health problem,which seriously affects the clinical diagnosis of hepatitis B and threatens the safety of blood transfusion.The concept of occult hepatitis B virus infection,the pathogenesis of occult hepatitis B virus infection,the prevalence of occult hepatitis B virus infection in different groups,including healthy population and different patients,and the possibility of transmission were summarized.The prevalence of occult hepatitis B virus infection was found in healthy population and different patients,and there is possibility of occult hepatitis B virus infection to be transmitted through blood transfusion.The paper provides a comprehensive introduction of the pathogenesis and prevalence of occult hepatitis B virus infection.More attention should be paid to occult hepatitis B virus infection.
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Occult hepatitis B virus infection is a worldwide public health problem,which seriously affects the clinical diagnosis of hepatitis B and threatens the safety of blood transfusion.The concept of occult hepatitis B virus infection,the pathogenesis of occult hepatitis B virus infection,the prevalence of occult hepatitis B virus infection in different groups,including healthy population and different patients,and the possibility of transmission were summarized.The prevalence of occult hepatitis B virus infection was found in healthy population and different patients,and there is possibility of occult hepatitis B virus infection to be transmitted through blood transfusion.The paper provides a comprehensive introduction of the pathogenesis and prevalence of occult hepatitis B virus infection.More attention should be paid to occult hepatitis B virus infection.
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Objective To study the prevalence of the occult hepatitis B virus infection (OBI) and the mutation of amino acid sequence in S gene of voluntary blood donors in AnHui/FuJian/Jiang Xi Province Blood centers.Methods Serologic testing for anti-HBc by ELISA was performed with HBsAg-HBV DNA+ samples from voluntary blood donors in three province blood centers.The S region of HBV of those samples was amplified and sequenced.The genotype and mutation of amino acid sequence were analyzed by MEGA6.Results 21 in 123046 blood donors from AnHui Province blood center were HBsAgHBV DNA+,the prevalence of OBI was 0.017％,and 76.2％ of these-OBI samples was positive in anti-HBc,S region was amplified by nest-PCR in 15 OBI samples,8 of them were B genotype,the others were C genotype.39 samples of 51 OBI blood donors from FuJian Province blood center were anti-HBc positive,16 samples of those OBI donors were amplified S region,14 were B genotype,the others were C genotype.There are 30 OBI blood donors from JiangXi Province blood center,24 of them were anti-HBc positive,S region was amplified in 4 samples,1 was B genotype,the others were C genotype.Of all 35 OBI samples,26 showed amino acid mutation,which was in MHR region of S gene,especially in HBV α epitope.Conclusion The rate of prevalence of OBI in AnHui Province was 0.017％,there was also certain OBI infection in FuJian and JiangXi Province.In the OBI samples which were amplified S region,the positive rates of anti-HBc in three blood centers were 73.3％,93.8％,100％.B Genotype was the main HBV genotype.The mutation in MHR region of S gene,especially in HBV α epitope,may be one of the reasons to cause OBI.
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Objective To investigate the role of mutations in C region that may contribute to occult hepatitis B virus infection.Methods C genes were amplified from two OBI blood donor samples respectively.Plasmids with mutations in C region of hepatitis B virus were constructed by overlapping PCR.HBsAg and HBeAg in Huh7 cells and in the serum of Balb/c mice were detected by CMLA.HBcAg in liver tissue was detected by immunohistochemistry,while HBV-RNA was tested by RT-PCR.Results Mutations in C region significantly reduced the expression level of HBeAg and HBcAg,but had no significant effect on HBsAg and HBV-RNA.Conclusion The mutations in C region affect the expression level of HBeAg and HBcAg,which may play an important role in the occurrence of OBI.