e antigen in acute hepatitis B.

To examine the association between e antigen and hepatitis-B surface antigen (HBs Ag) we studied 90 inpatients with acute viral hepatitis type B. e Antigen was present in 24 of the patients; these patients had detectable levels of HBs Ag for significantly longer than the 66 with no e antigen in their serum. The HBs Ag subtypes D (adw) and Y (ayw) were similarly distributed among patients with e antigen and among those without, and no differences in the results of biochemical liver function tests were observed between the two groups during the acute phase of illness. Three of the five patients who developed clinical and histological signs of chronic liver disease were positive for e antigen, a finding which supports the hypothesis that e antigen has a prognostic value in hepatitis B.     

Proteins of hepatitis B surface antigen.

Purified 22-nm forms of hepatitis B surface antigen (Hbsag) representing the three major antigenic subtypes (adw, ayw, and adr) were analyzed for their constituent polypeptides by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. No consistent difference in either the number or relative distributions of the polypeptides was observed for the various subtypes. Seven polypeptides were designated as P-1 through P-7 in order of their decreasing mobilities. By comparison with protein standards, their molecular weights were estimated as 23, 29.5, 36, 41.5, 53.5, 72, and 97 thousand. The P-1 and P-2 components represented the major polypeptides; P-2 and P-5 might by glycoproteins, based on their reaction with periodic acid-Shiff reagent. Each polypeptide contains cysteine residues. HBSAg was radiolabeled with 3H or 14C by reductive methylation or iodinated with 125I by the chloramine-T or lactoperoxidase procedures. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of labeled HBSAg yielded patterns identical to those obtained with protein stain. Comparison of HBSAg labeled by the chloramine-T and lactoperoxide procedures indicated that there was no distinction between internal or external components within the 22-nm structure.     

待孕夫妇乙肝表面抗原及乙肝表面抗体阳性情况分析

目的 分析与探讨待孕夫妇乙肝表面抗原及乙肝表面抗体检测结果,并研究其对临床孕前检查的影响及评价。方法 随机选取2015‒2017年度在我院进行孕前检查的夫妇2440对（4 880例）为研究对象,按照年度将待孕夫妇分为两组,每组2 440例,两组均加强孕前检查中的乙肝表面抗原（HBsAg）及乙肝表面抗体（HBsAb）的检测。A组为2015年3月‒2016年2月在我院进行乙肝表面抗原及乙肝表面抗体检查的待孕夫妇;B组为2016年3月‒2017年2月在我院进行乙肝表面抗原及乙肝表面抗体检查的待孕夫妇。比较两组待孕夫妇乙肝表面抗原及乙肝表面抗体检测的阳性结果。结果 B组HBsAg阳性率、HBsAb阳性率明显高于A组（6.43% vs 4.63%;62.99% vs 58.44%）,差异有统计学意义（P＜0.05）。B组、A组男性HBsAg阳性率明显高于同组女性（59.87% vs 40.13%;60.18% vs 39.82%）,HBsAb阳性率低于同组女性（46.52% vs 53.48%;47.41% vs 52.59%）,差异均有统计学意义（P＜0.05）。B组、A组高中及以上学历HBsAg阳性率明显低于同组高中以下学历（38.85% vs 61.95%;38.05% vs 61.15%）,高中及以上学历HBsAb阳性率高于同组高中以下学历（53.15% vs 46.84%;51.75% vs 48.25%）,差异均有统计学意义（P＜0.05）结论 目前夫妇乙肝感染仍处于增高趋势,对于进行孕前检查的待孕夫妇加强乙肝表面抗原及乙肝表面抗体的检测,有助于疾病的早期诊断、干预及治疗,能够减少乙肝传播,可有效降低新生儿乙肝发病率,促进优生优育,提高出生人口整体素质。     

Practical guidelines for assessing patients positive for hepatitis B surface antigen.

In assessing the patient the hepatitis B surface antigen (HBsAg) the physician must decide on the basis of physical findings, results of laboratory tests and biopsy, when indicated, whether the patient is an asymptomatic carrier or has acute or chronic hepatitis. Asymptomatic carriers of HBsAg must be educated in personal hygiene and the possibility of transmission, should not be allowed to donate blood or breast-feed and should not work with blood products for human use or pharmaceutical products designated for intravenous use. However, it is otherwise not necessary to advise these individuals to change their profession.     

Detection of hepatitis B surface antigen in isolated hepatocytes.

HBsAg was detected by indirect immunofluorescent method in liver biopsy specimens of 60 symptom-free HBsAg positive volunteers. An effort was made to separate from the material intact cells suitable for studying HBsAg localization in the liver cells.     

Abnormal immune adherence and elimination of hepatitis B surface antigen/antibody complexes in patients with AIDS.

C3b-coated immune complexes (IC) adhere to complement receptor 1 (CR1) on human E in the circulation. E from AIDS patients have an acquired low CR1 number. To study immune adherence and IC elimination in AIDS, radiolabeled hepatitis B surface Ag/antibody complexes were injected i.v. in six AIDS patients and in 14 healthy controls. The binding of IC to E was reduced in AIDS patients (mean binding 2 min after injection: 24.9 +/- 13.3%) compared with healthy individuals (63 +/- 3.7%) (p = 0.0005). The low binding correlated directly with the number of CR1/E and to the capacity of these E to bind IC in vitro. During the first 15 min disappearance of IC was faster in AIDS patients than in normal subjects and correlated with CR1 number. Thereafter, elimination was very slow in AIDS patients, which suggested that a fraction of IC might be released back into the circulation similarly to what has been observed for C3b-coated E. When the data were analyzed with a mathematical model allowing for such release to occur, five of six AIDS patients had a high release rate compared with little or no release in normal individuals (p less than 0.001). Thus, low CR1 on E is responsible for defective immune adherence, and might determine abnormal disappearance of IC from the circulation as well.     

Lack of leukocyte migration inhibition by hepatitis B surface antigen in hepatocellular carcinoma patients.

Soluble part of hepatocellular carcinoma (HCC) tissue extracts with or without hepatitis B surface antigen (HBsAg) was tested against leukocytes of 13 histologically confirmed HCC patients. Inhibition of leukocyte migration was observed in 9 out of 13 cases when tested by soluble HCC extract containing HBsAg, while inhibition of lukocyte migration was observed in 8 out of 13 cases when tested by solublp greater than 0.05, by Fisher's exact test). In the meantime, soluble HCC extract with or without HBsAg did not significantly cause inhibition of leukocyte migration in 12 non-HCC patients. Therefore, it is concluded that inhibition of leukocyte migration in HCC patients is caused by the tumor-associated antigen, not caused by HBsAg.     

Thermal stability of hepatitis B surface antigen S proteins.

Thermal stability of hepatitis B surface antigen (HBsAg) has been studied by analyzing alterations in the native secondary structure and the antigenic activity. After heating for 19 h, circular dichrosim showed a cooperative transition with a midpoint at 49 degrees C. The conformational changes induced by temperature reduced the helical content of HBsAg S proteins from 49% at 23 degrees C to 26% at 60 degrees C and abolished the antigenic activity, as measured by binding to polyclonal antibodies. Furthermore, the six different antigenic determinants recognized by our panel of monoclonal antibodies were also shown to be dependent on the native structure of HBsAg proteins. Hence, it can be inferred that these epitopes are conformation-dependent. Binding of monoclonal antibodies to HBsAg protected the native structure of the corresponding antigenic determinant from thermal denaturation. In fact, binding of one of the monoclonals tested resulted not only in protection of the corresponding epitope, but also in a consistent increase of antibody binding with increasing temperature. Such an increase in antibody binding occurred simultaneously with an increase in the fluidity of surface lipid regions, as monitored by fluorescence depolarization of 1-(trimethylammoniophenyl)-6-phenyl-1,3,5-hexatriene. This correlation, along with the observation that lipids play an important role in maintaining the structure and antigenic activity of HBsAg (Gavilanes et al. (1990) Biochem. J. 265, 857-864), allow to speculate the certain epitopes of HBsAg which are close to the lipid-protein interface, are dependent on the fluidity of the surface lipid regions. Thus, any change in the physical state of the lipids could confer a different degree of exposure to the antigenic determinants.     

Long-term effect of interferon plus ribavirin on hepatitis B surface antigen seroclearance in patients dually infected with hepatitis B and C viruses

Background

Interferon-α/ribavirin combination therapy might promote hepatitis B surface antigen (HBsAg) seroclearance in patients dually infected with hepatitis B and C viruses (HBV/HCV), but the long-term effect remains unclear. We aimed to investigate the rate of and the factors associated with HBsAg seroclearance during long-term follow-up after interferon-α/ribavirin combination therapy in HBV/HCV dually-infected patients.

Methodology/Principal Findings

Eighty-one patients who received interferon-α/ribavirin combination therapy for 24 weeks with a follow-up period of >24 weeks were enrolled. HBV serological markers and HBV DNA were determined every 6 months. Early and late HBsAg seroclearance were defined as HBsAg loss in less or more than 6 months after end-of-treatment, respectively. Fifteen (18.5%) patients had HBsAg seroclearance during a mean follow-up period of 3.4 (0.5–5.1) years. The 5-year cumulative incidence was 25.6%. Baseline cirrhosis and HBV DNA negativity 1 year after end-of-treatment were independently predictive of HBsAg seroclearance with an odds ratio (OR), 95% confidence intervals (CI) of 16.6, 1.8–153 and 9.2, 1.4–62.1, respectively, by Cox regression hazard analysis. Four patients developed early and 11 developed late HBsAg seroclearance, respectively. Cox regression hazard analysis showed no factor was associated with early HBsAg seroclearance, whilst HBV DNA negativity 1 year after end-of-treatment was the only significant factor predicting late HBsAg loss (OR, 43.0; CI, 2.5–745). Five patients had HBsAg seroconversion with a 5-year cumulative incidence of 8.3%. HBV DNA negativity at baseline and one year after EOT had a trend for HBsAg seroconversion. HCV response did not correlate to HBsAg loss.

Conclusions

We demonstrated that interferon-α/ribavirin had long-term effect on HBsAg seroclearance in dually HBV/HCV-infected patients. Baseline cirrhosis and seroclearance of HBV DNA 1 year after end-of-treatment were significant factors associated with HBsAg seroclearance.     

Neutralization of hepatitis B virus surface antigen with immunoglobulin preparations

The in vitro experiments with immunoglobulin and blood plasma containing hepatitis B virus (HBV) markers, revealed that the control of immunoglobulin preparations for the presence of hepatitis B virus surface antigen (HBsAg), mandatory for Russia, was not sufficiently informative. The neutralization of HBsAg with specific antibodies to the level, not determined by the EIA method, reached not less than 24 ng/ ml in 2 hours of incubation and not less than 49 ng/ml in 24 hours of incubation, which, when evaluated in 1 lU of anti-HBs, was 34.6 +/- 0.9 ng and 70.7 +/- 1.8 ng of HBsAg respectively. The process of the formation of immune complexes depended mainly on the time of incubation of experimental samples and on the antibody--antigen proportion in the system. The neutralization of viruses by antibodies had no influence on the capacity of the polymerase chain reaction to detect HBV DNA.     

Isoprenylation mediates direct protein-protein interactions between hepatitis large delta antigen and hepatitis B virus surface antigen.

Hepatitis delta antigen (HDAg) consists of two protein species of 195 and 214 amino acids, respectively, which are identical in sequence except that the large HDAg has additional 19 amino acids at its C terminus and is prenylated. Previous studies have shown that the large HDAg and the surface antigen of hepatitis B virus (HBsAg) together can form empty hepatitis delta virus (HDV) particles. To understand the molecular mechanism of HDV virion morphogenesis, we investigated the possible direct protein-protein interaction between HDAg and HBsAg. We constructed recombinant baculoviruses expressing the major form of HBsAg and various mutant HDAgs and used these proteins for far-Western protein binding assays. We demonstrated that HBsAg interacted specifically with the large HDAg but not with the small HDAg. Using mutant HDAgs which have defective or aberrant prenylation, we showed that this interaction required isoprenylates on the cysteine residue of the C terminus of the large HDAg. Isoprenylation alone, without the remainder of the C-terminal amino acids of the large HDAg, was insufficient to mediate interaction with HBsAg. This study demonstrates a novel role of prenylates in HDV virion assembly.     

Patterns of circulating hepatitis B surface antigen variants among vaccinated children born to hepatitis B surface antigen carrier and non-carrier mothers

Hepatitis B virus (HBV) variants that possessed missense mutation within the neutralization epitope of the major S antigen as defined by amino acid residues (aa#) 124–147, termed the a determinant variants, were identified through a population-based serosurvey of 2,305 children of the vaccinated birth cohorts born after 1986. Data on the 678 nucleotides encoding the S antigen of HBV were available for 75 HBV strains that were collected from 63 vaccinated children and 12 unvaccinated or incompletely vaccinated children, and 21 HBV strains from 25 unvaccinated adults. Among the diverse patterns of one to three amino acid substitutions within the a determinant, 145-Arg occurred most frequently (5/14); other variants were: 126-Ala, 127-Thr, 126-Ser/131-Asn/133-Thr, 129-His, 129-Arg, 123-Asn/131-Ile, 133-Leu, 141-Glu, and 141-Arg/144-Ala. Only one of these variants occurred in the 16 hepatitis B surface antigen (HBsAg)-carrier children born to HBsAg-negative mothers, whereas 12 of these variants occurred in the 20 (50%) children born to HBsAg-positive mothers. In addition, early administration of HBV vaccine within the noenatal period increased the likelihood of the emergence of these variants to 64.7% (11/17). Five of the 21 (23.8%) unvaccinated HBsAg-carrier adults harbored the a determinant variants possessing mutations within aa# 125–136, i.e. the putative first loop formed by the cysteine disulfide bonds. Vaccinated children were likely to harbor HBV variants possessing mutations involving altered charge of side chains and/or its hydrophobicity of amino acid residues within the putative second loop between aa#140 and 146. Our data suggest that emergence of these HBV S gene mutants in the phase of HBV vaccination program would be most common among populations in whom perinatal/vertical transmission of HBV is most common, i.e. southeast Asian and the Taiwanese.     

Protection of chimpanzees from type B hepatitis by immunization with woodchuck hepatitis virus surface antigen.

Two chimpanzees immunized with woodchuck hepatitis virus (WHV) surface antigen (WHsAg) developed antibodies cross-reactive with hepatitis B virus (HBV) surface antigen (HBsAg). After challenge with HBV, one animal was completely protected and the other experienced a subclinical infection, without evidence of liver disease. Three woodchucks immunized with HBsAg developed antibodies to HBsAg which did not cross-react with WHsAg. After challenge with WHV, all three woodchucks developed typical acute infections with associated hepatic lesions. Serological studies with the cross-reactive antibodies raised in chimpanzees suggested that the protective epitopes of WHsAg were related to the group a specificity of HBsAg. These studies indicated that cross-protective epitopes are shared by HBV and WHV; however, the humoral response to these epitopes can vary among species.