In vitro immune responses to hepatitis B surface antigens S and preS2 during acute infection by hepatitis B virus in humans

This study evaluated the in vitro immune responses to different components of the hepatitis B surface antigen (HBsAg) over the course of acute hepatitis B virus (HBV) infection. Early in the convalescent phase of infection, while HBsAg was present in the serum, peripheral blood mononuclear cells (PBMCs) were stimulated with preS2 peptide or hepatitis B surface protein. Specific IgG directed to different components of HBsAg was produced without a polyclonal increase in total IgG production. Stimulation with preS2 peptide produced IgG to the preS2 peptide (anti-preS2) and to the S antigen (anti-HBs). Hepatitis B surface protein stimulation produced anti-HBs but not anti-preS2. After this initial reactive phase, the PBMCs did not produce specific antibody when stimulated with either component of HBsAg; this effect lasted greater than 1 year. At some time 1-2 years after acute infection, the pattern of in vitro S antigen- and preS2 antigen-stimulated anti-HBs response reemerged in the PBMCs. Reemergence of sustained preS2 peptide-stimulated anti-preS2 response was not observed.     

Impact of hepatitis B virus (HBV) preS/S genomic variability on HBV surface antigen and HBV DNA serum levels

To evaluate whether hepatitis B virus (HBV) preS/S gene variability has any impact on serum hepatitis B surface antigen (HBsAg) levels and to analyze the replication capacity of naturally occurring preS/S variants, sera from 40 untreated patients with HBV-related chronic liver disease (hepatitis B e antigen [HBeAg]-positive, n = 11; HBeAg-negative, n = 29) were virologically characterized. Additionally, phenotypic analysis of three different preS/S variant isolates (carrying a 183-nucleotide deletion within the preS1 region, the deletion of preS2 start codon, and a stop signal at codon 182 within the S gene, respectively) was performed. HBV infecting 14 (35%) patients had single or multiple preS/S genomic mutations (i.e., preS1 and/or preS2 deletions, preS2 start codon mutations, C-terminally truncated and/or "a" determinant mutated S protein). Presence of preS/S variants negatively correlated with HBsAg titers (r = -0.431; P = 0.005) and its prevalence did not significantly differ between HBeAg-positive and HBeAg-negative patients. No correlation was found between HBsAg and HBV DNA levels in patients infected with preS/S mutants, whereas a significant correlation was found between HBsAg and viremia levels (r = 0.607; P = 0.001) in patients infected with wild-type HBV strains. HepG2 cells replicating the above-mentioned three preS/S variants showed significant reduction of HBsAg secretion, retention of envelope proteins in the endoplasmic reticulum, less efficient virion secretion and nuclear accumulation of significantly higher amounts of covalently closed circular DNA compared with wild-type HBV replicating cells. CONCLUSION: In patients infected with preS/S variants, HBV DNA replication and HBsAg synthesis/secretion appear to be dissociated. Therefore, the use of HBsAg titer as diagnostic/prognostic tool has to take into account the frequent emergence of preS/S variants in chronic HBV infection.     

HBV基因型和S基因序列特点与慢性乙型肝炎患者HBsAg/抗-HBs共存关系

目的探讨HBV基因型及S基因序列特点与慢性乙型肝炎（CHB）患者HBsAg和抗-HBs共存的内在相关性以及HBsAg＋/抗-HBs＋的发生机制及意义。方法共收集49例HBsAg＋/抗-HBs＋CHB患者的血清HBVDNA样本,采用PCR-RFLP及测序法鉴定其基因型,并与267例HBsAg＋/抗-HBs-CHB患者的HBV基因型分布进行比较。对6例HBsAg＋/抗-HBs＋CHB患者（Ⅰ组）的HBVS基因进行克隆测序,并与HBsAg＋/抗-HBs-CHB患者（Ⅱ组）进行对比,分析变异种类及频率等的差异。结果 HBsAg＋/抗-HBs＋CHB患者HBV基因型B、C及B/C混合感染的构成比分别为63.3%（31/49）、26.5%（13/49）、10.2%（5/49）,而对照组上述构成比分别为52.8%（141/267）、46.1%（123/267）、1.1%（3/267）,两组构成比差异有统计学意义（P〈0.01）。Ⅰ组HBsAg各区段,特别是主要亲水区（MHR）的变异位点明显多于Ⅱ组;发现了若干新变异、少见的W196和C69终止突变,1例患者检测到G145R变异。某些患者HBsAgMHR-2（包含a决定簇）并未发现变异。结论 HBV基因型的差异及HBsAg变异增多可能是部分CHB患者出现HBsAg＋/抗-HBs＋的原因之一;基因型B或B/C混合感染相对更易出现HBsAg＋/抗-HBs＋。HBsAg变异增多是CHB患者出现HBsAg＋/抗-HBs＋的重要机制之一。某些患者HBsAgMHR-2并无变异,提示HBsAg/抗-HBs共存还存在其他机制。     

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

AIM: To investigate the clinical significance and presence of mutations in the surface (S) and overlapping polymerase gene of hepatitis B patients with coexisting HBsAg and anti-HBs. METHODS: Twenty-three patients with chronic hepatitis B were studied. Of the 23 patients, 11 were both positive for hepatitis B virus (HBV) surface antigen (HBsAg) and antibody to HBV surface antigen (anti-HBs), 12 were negative for anti-HBs while positive for HBsAg. DNA was extracted from 200μL serum of the patients. Nucleotide of the surface and overlapping polymerase gene from HBV-infected patients was amplified by PCR, and the PCR products were sequenced. RESULTS: Forty-one mutations were found within the surface gene protein of HBV in 15 patients (10 with coexisting HBsAg and anti-HBs). Six (14.6%) out of 41 mutations were located at "α" determinant region in 5 patients (4 positive for HBsAg and anti-HBs). Eleven mutations (26.8%) occurred in the downstream or upstream of "α" determinant region. Lamivudine (LMV)-selected mutations were found in three patients who developed anti-HBs, which occurred in amino acid positions (196, 198, 199) of the surface protein and in YMDD motif (M204I/V) of the polymerase protein simultaneously. Presence of these mutations did not relate to changes in ALT and HBV DNA levels. CONCLUSION: Besides mutations in the "α" determinant region, mutations at downstream or upstream of the "α" determinant region may contribute to the development of anti-HBs. These mutations do not block the replicating competency of HBV in the presence of high titer of anti-HBs.     

Novel hepatitis B virus surface antigen mutations associated with occult genotype B hepatitis B virus infection affect HBsAg detection

The causative factors of occult hepatitis B infection are complicated and not yet been fully elucidated. Mutations in hepatitis B virus (HBV) S gene are one of the factors may contributing to occult infection. In this study, 89 blood donors with genotype B occult HBV infection were investigated. Fifty‐seven hepatitis B surface antigen (HBsAg)‐positive/HBV DNA‐positive blood donors served as control group for comparison. Occult HBV‐related mutations with a high incidence (P < .05) in the S gene were identified. To further verify these occult infection‐related mutations, a conservative full‐gene expression vector of HBV B genotype (pHBV1.3B) was constructed. Then, the mutant plasmids on the basis of pHBV1.3B were constructed and transfected into HepG2 cells. Extracellular as well as intracellular HBsAg was analysed by electrochemical luminescence and cellular immunohistochemistry. Ten occult infection‐related mutations (E2G, Q101R, K122R, M133T, D144E, G145R, V168A, S174N, L175S and I226S) were significantly more frequent in the occult infection group (P < .05). Five of the ten mutations (E2G, D144E, G145R, V168A and S174N) strongly decreased extracellular HBsAg level (P < .05) in the transfection system. Notably, the E2G mutation had the most significant impact on the ratio of extracellular HBsAg (3.8% vs pHBV1.3B) and intracellular HBsAg (239.3% vs pHBV1.3B) (P < .05), and the fluorescence density of E2G mutant HBsAg was significantly higher than that of pHBV1.3B (P < .0001). Hence, ten mutations were associated with genotype B occult HBV infection; E2G and V168A were novel mutations which we confirmed significantly affect HBsAg detection. E2G might cause HBsAg secretion impairment that results in intracellular accumulation and a decrease in HBsAg secretion.     

HBsAg-negative hepatitis B virus infections in hepatitis C virus-associated hepatocellular carcinoma

This study was conducted to evaluate reports that hepatitis B virus (HBV) DNA sequences can be found in the serum and/or tumour tissue from some hepatocellular carcinoma (HCC) patients who have no detectable hepatitis B surface antigen (HBsAg) in their sera. Such HBV infections would be highly atypical, because prospective studies have shown a clear succession of specific serologic markers during and after most HBV infections. As most HBsAg-negative HCC patients in Japan have hepatitis C virus (HCV) infections, the present study was conducted to determine whether some of these patients actually have unrecognized HBV infections. Thirty newly diagnosed HCC patients from Kurume, Japan, with antibody to the hepatitis C virus (anti-HCV) were studied. None of the 30 had HBsAg detectable in their serum. Of 22 for whom test results for antibodies to the hepatitis B core antigen (anti-HBc) and antibodies to HBsAg (anti-HBs) were available, 14 (64%) had anti-HBc and anti-HBs, four (18%) had anti-HBc alone, and four (18%) had no HBV markers. Nested polymerase chain reaction was used to detect the HBV surface (S), core (C), polymerase (P) and core promoter gene sequences in the HCC tissues and in the adjacent nontumorous liver tissues. HBV DNA was detected in HCC and/or adjacent nontumorous liver in 22 of 30 (73%) patients [detected in both HCC and nontumorous liver in 19/30 patients (63%)]. Among the 22 patients with detectable HBV DNA, more than one HBV gene was detected in 10 (46%). Among the four patients whose sera were negative for all HBV markers, three had HBV DNA in either HCC and nontumorous liver (two cases) or only in the nontumorous liver (one case); HBV DNA could not be detected in tissues from the fourth patient. In 18 of 21 (86%) patients with detectable HBV core promoter sequences, mutations at both nucleotides 1762 (A-GT) and 1764 (G-A) in the core promoter region were found. No deletions were detected in the core promoter gene region of the type reported to be associated with some cases of HBsAg-negative HBV infection. Thus, HBV DNA was detectable in 22 (73%) HBsAg-negative, anti-HCV-positive HCCs, including three (10%) who were also negative for anti-HBc and anti-HBs. HBV mutations at both nucleotides 1762 (A-GT) and 1764 (G-A) in the core promoter region were found in the majority of cases, mutations that have previously been reported in HBV that is integrated in HCC DNA. In serologic surveys to determine etiologic associations of HCC, patients such as those in this study would have been incorrectly designated as having 'HCV-associated HCC,' whereas the data in this study suggest that HBV could have played a role in the development of their HCCs.     

Presence of antibodies to the hepatitis B surface antigen is associated with an excess risk for hepatocellular carcinoma among non-Asians in Los Angeles County,California

Hepatocellular carcinoma (HCC) exhibits a more than 50-fold variation in incidence worldwide. High-risk regions include East Asia and sub-Saharan Africa, while non-Asians in the United States constitute a low-risk population. We assessed 111 cases of histologically confirmed HCC and 128 community control subjects among non-Asians of Los Angeles County for the presence in serum of hepatitis B surface antigen (HBsAg), antibodies to HBsAg (anti-HBs), antibodies to the hepatitis B core antigen (anti-HBc), HBV DNA, and antibodies to the hepatitis C virus (anti-HCV). Anti-HCV positivity was significantly associated with a 12.6-fold increase in HCC risk (95% confidence limits = 4.7, 33.6). As expected, the presence of serum HBsAg and the presence of anti-HBc in the absence of anti-HBs were both positively associated with the risk of HCC. But most interestingly, among our study subjects, the presence of anti-HBs in the absence of HBsAg and HBV DNA (indicative of a resolved infection) was significantly related to a 4.7-fold increased risk for HCC (95% confidence limits = 2.2, 9.4). Overall, any serological evidence of prior HBV exposure was associated with a 9.4-fold elevation in HCC risk (95% confidence limits = 4.7, 18.7). The data also demonstrate a synergistic effect of HBV and HCV infections on the risk of HCC. We estimate that about 55% of HCC cases occurring in non-Asians of Los Angeles can be attributed to infection by the hepatitis B and/or C viruses.(Hepatology 1997 Jan;25(1):226-8)     

Wild-type and 'a' epitope variants in chronic hepatitis B virus carriers positive for hepatitis B surface antigen and antibody

AIMS: This study aims to examine the genomic variants of the 'a' epitope in chronic hepatitis B virus (HBV) carriers positive for both hepatitis B surface antigen (HBsAg) and antibody to HBsAg (anti-HBs). METHODS: Eighteen HBV carriers were studied. Hepatitis B virus (HBV) DNA was extracted and the 'a' epitope region was amplified and sequenced. RESULTS: Eighteen Chinese asymptomatic HBV carriers were studied. There were 13 patients who were positive for both HBsAg and anti-HBs. Of these, one patient had only wild-type HBV, three had a viral mixture, and five had only 'a' epitope variant HBV. Of the three patients with a viral mixture, all had variants in the less conserved region (123-137). Of the five patients with pure HBsAg mutants, three had variants in the less conserved region while two had variants in the highly conserved region. In this study with a limited number of patients, the serum alanine aminotransferase (ALT) levels were higher in patients with wild-type HBV, compared with those with either 'a' epitope variants or a viral mixture consisting of wild type and variants. CONCLUSION: Eight of the nine (89%) patients positive for both HBsAg and anti-HBs harbored an 'a' epitope variant. The lower ALT levels seen in patients who had either pure 'a' epitope variant or a mixture of wild type and mutants suggest that a closer monitoring of these 'a' epitope variants should be required, as patients carrying these infectious viral strains may remain asymptomatic.     

Frequency of concurrence of hepatitis B surface antigen and antibody in a large number of carriers in Okinawa, Japan

A large number of chronic hepatitis B surface antigen (HBsAg) carriers in Okinawa, Japan were tested for antibody to HBsAg (anti-HBs), by both radioimmunoassay and enzyme immunoassay methods. Concurrence of HBsAg and anti-HBs was found in 166 (26.1%). We found no clear predominance of either liver damage or hepatitis B e antigen (HBeAg) in the concurrent carriers studied. Antibody to pre-S2 antigen (anti-pre-S2) was detected in 16 (9.6%) of 166 subjects with concurrent markers, 15 of these 16 carriers were positive for antibody to HBeAg (anti-HBe). Anti-pre-S2 was correlated with anti-HBe rather than with anti-HBs. The distribution of HBsAg subtypes among carriers determined to have subtypes was 76.7% adw, 22.0% adr, 0.2% ayr, 0.9% adwr, and 0.2% adyr. The distribution of anti-HBs subtypes among concurrent carriers was 51.5% anti-r, 21.4% anti-w, 15.5% anti-d, and 10.7% anti-y. Concurrent carriers had HBsAg of one subtype and heterotypic anti-HBs. Because the HBsAg subtype ay is rare in this area, it is hard to believe that the concurrent carriers with anti-y were infected with hepatitis B virus of which the HBsAg subtype was ay. A dual infection was highly unlikely. It seems that some of the concurrent carriers correlate with compound subtypes adwr and adyr.     

Frequency of concurrence of hepatitis B surface antigen and antibody in a large number of carriers in Okinawa,Japan

A large number of chronic hepatitis B surface antigen (HBsAg) carriers in Okinawa, Japan were tested for antibody to HBsAg (anti-HBs), by both radioimmunoassay and enzyme immunoassay methods. Concurrence of HBsAg and anti-HBs was found in 166 (26.1% ). We found no clear predominance of either liver damage or hepatitis B e antigen (HBeAg) in the concurrent carriers studied. Antibody to pre-82 antigen (anti-pre-S2) was detected in 16 (9.6%) of 166 subjects with concurrent markers, 15 of these 16 carriers were positive for antibody to HBeAg (anti-HBe). Anti-pre-S2 was correlated wit anti-HBe rather than with anti-HBs. The distribution of HBsAg subtypes among carriers determined to have subtypes was 76.7% adw, 22.0% adr, 0.2% ayr, 0.9% adwr, and 0.2% adyr. The distribution of anti-HBs subtypes among concurrent carriers was 51.5% anti-r, 21.4% anti-w, 15.5% anti-d, and 10.7% anti-y. Concurrent carriers had HBsAg of one subtype and heterotypic anti-HBs. Because the HBsAg subtype ay is rare in this area, it is hard to believe that the concurrent carriers with anti-y were infected with hepatitis B virus of which the HBsAg subtype was ay. A dual infection was highly unlikely. It seems that some of the concurrent carriers correlate with compound subtypes adwr and adyr.     

乙型肝炎表面抗原和乙型肝炎e抗原双阳性的乙型肝炎病毒携带产妇进行母乳喂养的安全性

目的探讨乙型肝炎表面抗原(hepatitis B surface antigen,HBsAg)和乙型肝炎e抗原(hepatitis B e antigen,HBeAg)双阳性的乙型肝炎病毒(hepatitis B virus,HBV)携带产妇采用母乳喂养对其所生婴儿HBV感染率的影响.方法采用前瞻性队列研究方法,纳入2016年2月至2018年5月在浙江大学医学院附属妇产科医院进行产前检查及分娩的HBsAg和HBeAg双阳性携带HBV产妇及其所生的婴儿各323例,将其分为母乳喂养组和人工喂养组.采用化学发光免疫分析法和聚合酶链反应-荧光探针法,分别检测两组婴儿在出生<24 h及7月龄时的血清HBV标志物和HBV DNA的阳性率.统计学方法采用x2检验.结果最终纳入297例患者,其中母乳喂养组149例,人工喂养组148例.母乳喂养组与人工喂养组婴儿在出生<24 h及7月龄时的HBsAg、抗-HBs、HBeAg、HBV DNA>100 IU/mL的阳性率比较,差异均无统计学意义(均P>0.05).母乳喂养组出生<24 h新生儿抗-HBs阳性率为58.39%(87/149),低于7月龄时的95.97%(143/149);母乳喂养组出生<24 h新生儿HBeAg阳性率为65.10%(97/149),高于7月龄时的13.42%(20/149);差异均有统计学意义(x2=59.75、40.49,均P<0.01).母乳喂养组出生<24 h新生儿的HBsAg和HBV DNA>100 IU/mL阳性率分别为2.01%(3/149)和2.68%(4/149),其7月龄时的HBsAg和HBV DNA>100 IU/mL阳性率分别为2.68%(4/149)和2.68%(4/149),两个时间点比较差异均无统计学意义(均P>0.05).人工喂养组出生<24 h新生儿抗-HBs阳性率为47.97%(71/148),低于7月龄时的95.94%(142/148);人工喂养组出生<24 h新生儿HBeAg阳性率为55.41%(82/148),高于7月龄时的19.59%(29/148);差异均有统计学意义(x2=85.37、39.84,均P<0.01).人工喂养组出生<24h新生儿的HBsAg和HBV DNA>100IU/mL阳性率分别为4.73%(7/148)和1.35%(2/148),其7月龄时的HBsAg和HBV DNA>100 IU/mL阳性率分别为1.35%(2/148)和1.35%(2/148),两个时间点比较差异均无统计学意义(均P>0.05).结论母乳喂养不是增加HBsAg和HBeAg双阳性HBV携带产妇垂直传播风险的决定性因素,建议这类产妇在正规预防的前提下进行母乳喂养.     

Molecular characterization of hepatitis B virus surface antigen mutants in Singapore patients with hepatocellular carcinoma and hepatitis B virus carriers negative for HBsAg but positive for anti‐HBs and anti‐HBc

Background and Aims : Mutations on the a‐determinant of hepatitis B virus surface antigen (HBsAg), capable of escaping detection and vaccination, are identified in HBsAg‐positive/anti‐HBs‐positive vaccinated infants. We studied the prevalence of these mutants in HBsAg‐negative/anti‐HBc‐positive chronic HBV carriers and patients with hepatocellular carcinoma (HCC). Methods : DNA sequence coding for the antigenic a‐determinant of HBsAg was amplified from either HCC genomic DNA or serum samples of the selected patients and sequenced. The replicative mutant genomes were reconstituted in vitro and their reactivity to commercial kits measured. Results : Mutations within and/or outside the a‐determinant were identified in patients seronegative for HBsAg. They were then reconstituted in vitro and transiently transfected into HepG2 cells. Culture medium containing secreted HBV viral particles was collected and assayed for their binding to commercial kits. Drastic decrease of reactivity to these kits was seen with most of the identified mutations, including those located outside the a‐determinant. Conclusion : The existence of a more complex antigenic structure of HBsAg is indicated by the decreased reactivity to detection of mutations, some of which are outside the a‐determinant, escape vaccination and may persist in seronegative patients. The high proportion of HBsAg mutants that are integrated in HCC genomes suggests a role of these mutants in hepatocarcinogenesis, possibly leading to mutant HBV‐related HCC. © 2002 Blackwell Publishing Asia Pty Ltd     

Detection of different viral strains of hepatitis B virus in chronically infected children after seroconversion from HBsAg to anti-HBs indicating viral persistence

Background/Aims: Seroconversion to anti-HBs or the loss of HBsAg is usually associated with complete elimination of the replicative hepatitis B virus. Usually in these patients hepatitis B virus DNA (HBV DNA) becomes undetectable. Routine controls of patients who underwent anti-HBs seroconversion by more sensitive tests showed that in some cases the virus persisted in the patient. Therefore the aim of our study was to evaluate if virus persistence could also be found in children with chronic hepatitis B after anti-HBs seroconversion. The virus pool should be characterized before and after seroconversion.Methods: Viral DNA was extracted from nine HBsAg negative or anti-HBs positive sera of children, previously diagnosed as chronic HBsAg carriers. HBV DNA was amplified by polymerase chain reaction. Subsequently the nucleotide sequences of the polymerase chain reaction product in the a-determinant region (aa 121–161) were analyzed on an automatic fluorescent sequencer.Results: In the sera of seven children, HBV DNA was detected in the HBsAg negative phase of the HBV infection. Mutations in codons 122, 125, 127, 131, 134, 143, 159 and 161 of the S gene could be documented, resulting in amino acid changes. In three patients the sequence analysis revealed changes in the HBV genotype from genotype A (serotype adw) to genotype D (serotype ayw) during seroconversion to anti-HBs.Conclusions: These data demonstrate that persistence of the hepatitis B virus can also occur in HBsAg negative and anti-HBs positive children. After loss of HBsAg, no specific HBV variant was identified. Although a conclusive explanation for the selection process cannot be provided, it remains a fact that the ‘surviving’ viral strain was mostly represented by genotype D.     

Significant association of different preS mutations with hepatitis B-related cirrhosis or hepatocellular carcinoma

Background

The associations of nucleotide substitution mutations in the preS region of hepatitis B virus (HBV) with hepatocellular carcinoma (HCC) and cirrhosis remain unknown. We aimed to determine the associations of preS mutations with HCC or cirrhosis.

Methods

HBV from 603 asymptomatic hepatitis B surface antigen carriers (ASCs), 219 chronic hepatitis B (CHB) patients, 119 cirrhosis patients, and 231 HCC patients were genotyped and sequenced in the preS region. Nucleotides with the highest frequencies in HBV from the hepatitis B e antigen (HBeAg)-positive ASCs were treated as “wild-type” nucleotides. Twenty-one preS1 mutations and 14 preS2 mutations were evaluated. Multivariate regression analyses were applied to determine factors independently associated with cirrhosis or HCC.

Results

Most (85.7%) preS2 mutations were associated with CHB compared with ASCs, whereas most preS1 mutations were associated with HCC compared with the cirrhosis patients or CHB patients. Compared with the CHB patients, 81.0% preS1 mutations in genotype C were inversely associated with cirrhosis. Multivariate regression analyses showed that C2964A, C3116T, and C7A were novel factors associated with HCC compared with those without HCC, whereas A2964C and T3116C were independently associated with cirrhosis compared with ASCs and the CHB patients. Combined preS1 mutations had specificities greater than 95%, while C3116T and C7A had moderate sensitivities and specificities, for HCC.

Conclusions

C2964A, C3116T, and C7A are novel markers independently associated with an increased risk of HCC, while A2964C and T3116C are novel markers independently associated with an increased risk of cirrhosis. Combined preS1 mutations are specific for HCC.     

Pitfall of hepatitis B surface antigen testing in a kidney transplant recipient presenting hepatitis B reactivation

Diagnosis of hepatitis B virus (HBV) infection based on hepatitis B surface antigen (HBsAg) detection can be hampered in the setting of HBV reactivation in immunocompromized patients with prior serology indicating past cured infection, and can be associated with severe or fulminant and fatal hepatitis. We present a case of HBV reactivation in a renal transplant patient in whom HBsAg failed to be confirmed as a true positive result. One year after transplantation, systematic testing showed HBsAg positivity with a titer at 244 pg/mL, anti-hepatitis B core antibody and concurrent anti-hepatitis B surface antibody positivity. Confirmation of HBsAg detection by seroneutralization did not confirm HBsAg positivity, indicating that HBsAg detection was a false positive result. Notwithstanding, HBV DNA titer in serum was concurrently 8.6 Log IU/mL. HBV DNA sequencing showed a genotype D and several amino acid substitutions within HBsAg, including some previously involved in impaired diagnosis and altered immunogenicity. Although no perturbation of liver biochemical markers was observed, treatment with tenofovir was introduced. One month later, HBV DNA level had decreased by 2.6 Log IU/mL and no clinical and biochemical symptoms of hepatitis had occurred. The present case underlines that serologic diagnosis of HBV reactivation can be tricky in transplant recipients with a prior serology indicating past HBV infection. This prompts to perform HBV DNA testing in case of positive HBsAg testing, regardless of the result of neutralization by anti-HBs antibodies.     

Hepatitis B virus infection after renal transplantation in the presence of antibody to hepatitis B surface antigen immunity

BACKGROUND AND AIM: Hepatitis B virus (HBV) infection has been known to be hampered by immunity against hepatitis B surface antigen (HBsAg). However, HBV with mutations within the common antigenic epitope of HBsAg, the "a" determinant region, can escape from humoral immunity. Moreover, HBV infection by "a" determinant mutants in chronic HBV patients has been reported after renal transplantation. In the present study, the authors investigated HBV infection after renal transplantation despite passive immunization or resolved HBV infection. METHODS: A total of 1682 patients who underwent a renal transplant between 1979 and 1998 at the Severance Hospital, Yonsei University College of Medicine, Korea, were enrolled. The sequence of the HBV genome was analyzed from two patients with antibody to HBsAg (anti-HBs) immunity. RESULTS: Of 1682 patients who were HBsAg negative before transplantation, 21 patients were found to be HBsAg positive, with elevated aspartate aminotransferase and alanine aminotransferase levels after transplantation. Interestingly, six of 21 (28.6%) patients were anti-HBs positive before the transplantation. Sequence analysis of the cloned HBV from two of six patients with anti-HBs immunity showed no evidence of significant mutations within the "a" determinant region, suggesting a wild-type of HBV. Their donors were not exposed to HBV before transplantation (all HBV markers were negative). Seven deaths of 21 patients were ascribed to HBV-related complications. CONCLUSIONS: Regardless of anti-HBs immunity, HBV infection occurred in immunosuppressed patients in a high endemic area. The molecular mechanism and clinical impact of HBV infection after renal transplantation in patients with anti-HBs immunity should be further reappraised.     

Meta‐analysis: Association between hepatitis B virus preS mutation and hepatocellular carcinoma risk

Previous observational studies suggested that hepatitis B virus (HBV) preS mutation plays an important role in the existence of HBV‐related hepatocellular carcinoma (HCC). However, the results are still debatable. With an increasing number of studies about this topic, this study employed a meta‐analysis to identify the association between HBV preS mutation and HCC risk. We searched for eligible studies from PubMed, ProQuest, CINAHL, ScienceDirect and Springer databases to assess the association between HBV mutation and HCC risk. This meta‐analysis was conducted using RevMan 5.3 to provide pooled estimate for odds ratio (ORs) with 95% confidence intervals (95% CIs). Twenty‐one clinical studies were included in this meta‐analysis study which consisted of 1738 participants with HBV‐related HCC and 3740 HBsAg‐positive patients without HCC. All studies used samples of Asian population. PreS deletion was the most common mutation found in all studies. We found that ORs of HBV overall preS deletion was associated with HCC (OR = 3.28; 95% CI = 2.32‐4.65; P < .00001; random‐effects model). Each preS1 and preS2 deletion was associated with increased risk of HCC, with OR 2.42 (95% CI = 1.25‐4.68, P = .008) and 3.36 (95% CI = 2.04‐5.55, P < .00001), respectively. PreS2 start codon mutation was also significantly associated with HCC risk (OR = 2.47; 95% CI: 1.15‐5.27; P = .02; random‐effect model). The result of this meta‐analysis suggested that HBV preS deletion (all, preS1 and preS2) and preS2 start codon mutation might contribute to the increased risk of HBV‐related HCC.     

Lamivudine therapy for prevention of immunosuppressive-induced hepatitis B virus reactivation in hepatitis B surface antigen carriers

Viral reactivation in hepatitis B surface antigen (HBsAg) carriers undergoing immunosuppressive therapy is well documented. To evaluate the role of lamivudine prophylaxis in Hepatitis B virus (HBV) carriers treated with immunosuppression for nonhepatic disorders, we reviewed our experience between 1997 and 2000 at Hadassah University Hospital (Jerusalem, Israel). Controls were patients who were HBV carriers and who, between 1990 and 1995, were treated for hematological malignancies but were not treated with lamivudine. Eighteen HBsAg-positive patients were treated with immunosuppression. Fourteen were males, with a mean age of 48 years. Eleven patients had lymphoma; 2 had colonic adenocarcinoma; and 5 had cryoglobulinemia, enophthalmitis, vasculitis, malignant histocytosis, or ulcerative colitis. Fourteen patients were treated with chemotherapy, and 4 with prolonged high-dose corticosteroids. All patients were HBsAg-positive; 4 had hepatitis B e antigen, and 10 had HBV DNA by polymerase chain reaction. Lamivudine was administered to 13 patients in the treatment group 1 to 60 days (mean, 15 days) before immunosuppressive treatment and continued 0.5 to 24 months (mean, 7 months) following initiation of immunosuppression. Mean follow-up after lamivudine administration was 21 months. Three patients died of lymphoma complications and 10 (77%) survived. None of the patients had clinical or serological evidence of HBV reactivation during or after lamivudine prophylaxis. Of 6 patients who presented with liver function test disturbances, 5 improved during combined lamivudine and immunosuppression treatment. At the end of follow-up, HBV DNA became undetectable in 2 of 10 patients. In 2 patients, seroconversion from HBsAg to anti-HBs was observed. In contrast, 2 of 5 control patients had HBV reactivation. Lamivudine prophylaxis in HBsAg carriers receiving immunosuppressive therapy may prevent HBV reactivation and hepatic failure.