Hepatocyte localization of hepatitis B core and surface antigens in renal transplant recipients

Summary A prospective series of 45 liver biopsies taken from 22 renal transplant patients was investigated for the presence of hepatitis B antigen core (HBc) and surface (HBs) components by electron microscopy. At the time of each biopsy serum HBs Ag was sought by radioimmunoassay. Sections were taken for the detection of HBs Ag by immunofluorescence.In seropositive patients, intravesicular tubular structures resembling HBs Ag were found in 61% of biopsies while the intranuclear core HBc was present in 69%. No correlation could be made between the ultrastructural pattern of the viral components and the intensity of the histological liver damage. During the follow up, there was an accumulation of both HBs and HBc Ag even in a period as short as 1 year. The 9 liver specimens examined after three years of transplantation showed a marked accumulation of both antigens. Thus the expression of HB Ag at the hepatocellular level seems to correlate better with the duration of antigenaemia than with the histological pattern.Lastly, on matched semithin and ultrathin sections, the ground glass appearance of cytoplasm appeared to correlate with smooth endoplasmic reticulum distorsion, irrespective of the simultaneous presence or absence of intravesicular tubular structures. The sanded nuclei expressed a rare massive accumulation of core antigen.     

Specificity and sensitivity of the IgM capture immunoassay: studies of possible factors inducing false positive or false negative results

The specificity and sensitivity of the IgM-capture immunoassay (IgM-CI) were evaluated for detection of rubella specific IgM and hepatitis B core (HBc) specific IgM. For rubella specific IgM, antibodies bound to the solid phase were detected by haemadsorption and for HBc specific IgM, by using HBc antigen (HBcAg) and radiolabelled IgG anti-HBc. Rheumatoid factor (RF) was found to interfere in the test for HBc specific IgM because IgM-RF bound to the solid phase reacted with aggregated radiolabelled HBc specific IgG. This false positive reaction did not occur when radiolabelled F(ab')2 was used instead of the whole IgG molecule. HBcAg purified from biological fluids might be coated with host IgG and under these conditions, HBcAg could react with RF. It was also demonstrated that high levels of IgG antibodies could interfere with IgG anti-mu coated-surface by means of non-immunological protein-protein interactions. In fact, IgG did not interfere in the rubella assay, whereas it did in the very sensitive anti-HBc test. To prevent this false-positive reaction, different dilution media were tested. Only the addition of non-specific IgG and fetal calf serum (FCS), to the dilution medium, seems to improve the specificity of the test. Furthermore, in order to decrease this non-specific IgG-IgG interaction and an occasional prozoning phenomenon, the dilution of serum to be tested was taken into account. Parameters considered to decrease sensitivity were also studied. RF, anti-F(ab')2 antibodies and non-specific IgM did not decrease significantly the sensitivity of the assay.     

腺病毒转染法构建表达乙型肝炎病毒核心蛋白小鼠肝癌细胞系及其在乙肝疫苗评价中的应用

目的 构建一种可高效表达乙型肝炎病毒(Hepatitis B virus,HBV)核心蛋白(HBc)C57BL/6小鼠来源肝癌细胞系,并以其作为靶细胞评价乙肝基因疫苗在C57BL/6小鼠体内所引起的HBc特异性细胞毒性T细胞(CTL)的活性.方法 以HBV全基因组为模板,采用PCR方法扩增HBc基因,插入AdEasy腺病毒穿梭载体,构建携带HBc蛋白的腺病毒穿梭载体AD-HBc,电转携带有腺病毒骨架质粒(Ad-Easy)的E.coli BJ5183感受态细胞,获得重组腺病毒质粒AD-CMV-HBc,经PmeⅠ线性化处理后转染HEK293细胞进行包装得到相关的重组腺病毒,再感染C57BL/6小鼠来源肝癌细胞系Hepa1-6.结果 成功构建表达HBc蛋白的重组腺病毒,在体外对Hepa1-6细胞的感染率几乎为100％,并且HBc蛋白得到高效表达.以此为靶细胞用于pVAX1-HBc基因疫苗免疫C57BL/6小鼠产生的CTL活性的体外检测.结论 我们成功构建HBc蛋白表达的靶细胞系,对研究乙肝病毒核心抗原(HBcAg)所引起的细胞免疫反应及乙肝发病机理等方面有重要意义.     

Meta‐analysis of the association between anti‐HBc seropositivity and a poor prognosis of chronic HCV infection

Aim: The impact of serological HBsAg? and anti‐HBc+ on the prognosis of chronic hepatitis C virus (HCV) infection is unknown. We conducted a systematic review to analyze whether anti‐HBc positivity imposes any effect on the course of HCV‐related chronic liver disease. Methods: We retrieved references from online databases that included PubMed and EMBASE. Data were gathered with regard to demographic information, disease progression and prognosis, and the results of serological tests. The development of hepatocellular carcinoma (HCC) was the endpoint of follow‐up of all cohort studies. Results: Eighteen references were included in this study, of which four were cohort studies. Twelve studies were retrospective, observational and non‐interventional studies. According to our meta‐analysis, the rate of serological HBsAg? and anti‐HBc+ was higher among HCC patients compared with non‐HCC patients (odds ratio [OR], 1.55; 95% CI, 1.22–1.98). HCV patients that were anti‐HBc+ had a greater chance of developing HCC than their anti‐HBc? counterparts (OR, 2.15; 95% CI, 1.34–3.47). Conclusions: The serological status of HBsAg? and anti‐HBc+ appears to be correlated with a poor prognosis for chronic HCV infection. Though the general quality of these references was low, and multiple confounding factors existed, the likelihood of a poorer outcome of HCV patients that are positive for anti‐HBc should be considered by their physicians.     

Significance of detecting anti‐HBc among Egyptian male blood donors negative for HBsAg*

Background: Screening for hepatitis B virus surface antigen (HBsAg) reduces the risk of transfusion‐transmitted hepatitis B viral (HBV) infection. However, the absence of HBsAg in the blood of apparently healthy individuals may not be sufficient to ensure the lack of circulating HBV. Blood containing anti‐hepatitis B core antibody (anti‐HBc) without detectable presence of HBsAg might be infectious; therefore, screening for anti‐HBc has been implemented in some countries resulting in a decrease in the risk of post‐transfusion HBV infection. Aim: To study the seroprevalence of anti‐HBc. The relationship between anti‐HBc positivity and the presence of circulating HBV among healthy blood donors negative for HBsAg will be helpful to decide whether supplemental testing may bring additional safety to blood products. Material and methods: A total of 1026 serum samples collected from HBsAg‐negative Egyptian healthy male donors were tested for the presence of anti‐HBc (both IgM and IgG types) using the competitive enzyme‐linked immunosorbent assay technique. Anti‐HBc‐positive samples were subjected to real‐time polymerase chain reaction to confirm the presence of HBV DNA. Results: Of the 1026 samples tested, 80 (7·8%) blood samples were found to be reactive to anti‐HBc. Of those, HBV DNA was detected in five of the samples (6·25%). The levels of detected viraemia were variable among the five donors. Conclusion: This study shows the insufficient effectiveness of HBsAg screening in protecting blood recipients from HBV infection. Inclusion of anti‐HBc testing should be considered in the screening of blood donors.     

乙肝患者血清HBV—DNA与e,c系统相关分析及临床意义

对３７４乙型肝患者血清用地高辛探针法检测ＨＢＶ－ＤＮＡ；用酶联法检测ＨＢｅＡｇ、抗ＨＢｅ、ＨＢｃＡｇ、抗ＨＢｃ－ＩｇＭ。结果：ＨＢＶ－ＤＮＡ与ＨＢｅＡｇ、抗ＨＢｅＡｇ、抗ＨＢｅ无明显相关（Ｐ〉０．０５），与ＨＢｃＡｇ、抗ＨＢＣ－ＩｇＭ呈正相关关系（ｒ＝０．１８－０．２，Ｐ〈０．０１）；ＨＢｅＡｇ组与抗ＨＢｅ组ＨＢＶ－ＤＮＡ检出率无明显差异（Ｐ〉０．０５），以ＨＢＶ－ＤＮＡ为标准评价ＨＢｅＡｇ、ＨＢ     

High risk of hepatitis B‐virus reactivation after hematopoietic cell transplantation in hepatitis B core antibody‐positive patients

We investigated the serological changes in hepatitis B virus (HBV)‐related markers in 55 and 26 hepatitis B surface antigen (HBsAg)‐negative patients undergoing allogeneic and autologous stem cell transplantation, respectively, over the past 4 yr. Five of the 17 allogeneic and one of the five autologous patients with pretransplant anti‐hepatitis B core antigen antibodies (anti‐HBc) were HBsAg‐positive after transplantation, whereas none of the patients negative for anti‐HBc were HBsAg‐positive in both groups. All patients who became HBsAg‐positive received steroid‐containing immunosuppressive therapy for chronic graft versus host disease (GVHD) or myeloma. Four of the six patients developed flare of HBV hepatitis, and two patients did not. One patient developed fulminant hepatitis treated with lamivudine and plasma exchange. Other five patients received entecavir from the detection of HBsAg. Although HBV‐DNA levels became below the limit of detection in all patients, HBsAg positivity remained in three patients after 6 months of treatment. We concluded that anti‐HBc positivity is a risk factor for reactivation of HBV after both autologous and allogeneic transplantation, and HBV‐related markers should be monitored regularly in these patients. We also stress the efficacy of pre‐emptive use of antiviral agents in controlling HBV replication and limiting hepatic injury due to reactivation of HBV in these patients.     

临沂市自然人群乙肝病毒感染状况调查

目的 了解临沂市自然人群ＨＢＶ感染状况。方法 整群、分层抽样确定调查对策，抽出检测ＨＢｓＡｇ、抗－ＨＢｓ、抗－ＨＢｃ、ＨＢｅＡｇ。结果 自然人群乙肝患病率为４８．０６／１０万，ＨＢｓＡｇ、抗－ＨＢｓ、抗－ＨＢｃ阳性率及ＨＢＶ感染率分别为７．１１％、２３．６４％、２７．７２％和４６．５９％。年龄上有０￣１０岁和２０￣４０岁两个感染高峰，４０岁后随年龄增高而降低。ＨＢｓＡｇ阳必具有明显的家庭聚集性，阳     

Virological profiles in hepatitis B virus inactive carriers: monthly evaluation in 1-year follow-up study.

STUDY SUBJECT: We longitudinally evaluated the virological behaviour and the hepatitis B virus (HBV) genomic variability in inactive HBV surface antigen (HBsAg) chronic carriers. PATIENTS AND METHODS: Fourteen HBsAg-positive healthy workers (13 inactive carriers and 1 with active HBV infection) were followed up for 12 months by monthly evaluation of aminotransferase, HBV DNA, and IgM anti HBV core antigen (IgM anti-HBc) values. Moreover, HBV serum isolates from each case were amplified, cloned and sequenced to evaluate the presence of the potentially clinical relevant core-promoter and precore mutations. The same technical procedures were used to examine the S gene of isolates from 3 randomly selected inactive carriers and the patients with active HBV infections. RESULTS: Aminotransferase values were constantly normal in all cases. Viremia levels appear to fluctuate widely over time in each individual case, although the HBV DNA remained below 2 x 10(4) copies/ml in all samples. Only four serum samples from two inactive carriers had IgM anti-HBc values higher than the specific cut-off limit of the assay. Either wild type or core-promoter/precore HBV variants or a mixture of them were detected in the inactive carriers. S gene nucleotide homology among the clones from the three inactive carriers and the subject with active infection was 98.9%, 98.3%, 98.1% and 98.2%, respectively. CONCLUSIONS: The degree of suppression of HBV replication in inactive carriers is variable over time, and the entity and quality of HBV variability is comparable between active and inactive carriers.