scholarly journals Expression Level of Small Envelope Protein in Addition to Sequence Divergence inside Its Major Hydrophilic Region Contributes to More Efficient Surface Antigen Secretion by Hepatitis B Virus Subgenotype D2 than Subgenotype A2

Viruses ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 967
Author(s):  
Qianru Wang ◽  
Shuwen Fu ◽  
Jing Zhang ◽  
Quan Yuan ◽  
Jisu Li ◽  
...  
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Surface Antigen ◽  
Envelope Protein ◽  
Hepatitis B Surface Antigen ◽  
Site Directed Mutagenesis ◽  
Enzyme Linked Immunosorbent Assay ◽  
S Protein ◽  
Huh7 Cells ◽  
B Virus

Hepatitis B surface antigen (HBsAg) promotes persistent hepatitis B virus (HBV) infection. It primarily corresponds to small (S) envelope protein secreted as subviral particles. We previously found that genotype D clones expressed less S protein than genotype A clones but showed higher extracellular/intracellular ratio of HBsAg suggesting more efficient secretion. The current study aimed to characterize the underlying mechanism(s) by comparing a subgenotype A2 clone (geno5.4) with a subgenotype D2 clone (geno1.2). Five types of full-length or subgenomic constructs were transfected to Huh7 cells at different dosage. HBsAg was quantified by enzyme linked immunosorbent assay while envelope proteins were detected by Western blot. We found that ratio of extracellular/intracellular HBsAg decreased at increasing amounts of DNA transfected. Conflicting findings from two types of subgenomic construct confirmed stronger secretion inhibitory effect of the genotype D-derived large envelope protein. Chimeric constructs followed by site-directed mutagenesis revealed geno1.2 specific V118/T127 and F161/A168 in the S protein as promoting and inhibitory of HBsAg secretion, respectively. In conclusion, more efficient HBsAg secretion by subgenotype D2 than subgenotype A2 is attributed to lower level of S protein expression in addition to V118 and T127 in S protein, although its F161 and A168 sequences rather reduce HBsAg secretion.

scholarly journals Development and Technical and Clinical Validation of a Quantitative Enzyme-Linked Immunosorbent Assay for the Detection of Human Antibodies to Hepatitis B Surface Antigen in Recipients of Recombinant Hepatitis B Virus Vaccine

2009 ◽  
Vol 16 (8) ◽  
pp. 1236-1246 ◽  
Author(s):  
Pierre Cambron ◽  
Jeanne-Marie Jacquet ◽  
Bernard Hoet ◽  
Marc Lievens
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Immunosorbent Assay ◽  
Surface Antigen ◽  
Hepatitis B Surface Antigen ◽  
Geometric Mean ◽  
Enzyme Linked Immunosorbent Assay ◽  
Analytical Sensitivity ◽  
Limit Of Quantitation ◽  
B Virus

ABSTRACT Pending removal from the market of a commercial assay (the AUSAB [Abbott Laboratories] enzyme immunoassay [EIA]) for the determination of antibodies to hepatitis B surface antigen (HBsAg), a new in-house quantitative enzyme-linked immunosorbent assay (ELISA) to measure antibodies against HBsAg (anti-HBs) was developed (anti-HBs in-house). Specific anti-HBs antibodies were sandwiched between the precoated HBsAg ad and ay subtypes purified from plasma from hepatitis B virus (HBV) human carriers and the recombinant HBsAg adw2 subtype tagged with horseradish peroxidase. The assay was calibrated against the 1st International Reference Preparation for anti-hepatitis B immunoglobulin (lot 1977-W1042). Analytical sensitivity and the limit of quantitation were estimated at 0.43 mIU/ml and 2.0 mIU/ml, respectively. Overall reproducibility was 11.86%, and accuracy was estimated to be 94.89%. More than 4,000 samples from seven clinical trials were tested with the anti-HBs in-house assay and compared to results generated with AUSAB EIA and AUSAB radioimmunoassay (RIA). During the technical validation, the anti-HBs in-house assay was compared to the AUSAB RIA as a reference (n = 919). Overall assessment of concordance and Deming's regression analysis were performed. The coefficient of correlation between the AUSAB RIA and anti-HBs in-house assay was 0.9815 with a slope of 0.9187. The overall agreement between anti-HBs in-house and AUSAB RIA was 97.61%, considering the clinical cutoffs at 3.3 mIU/ml and 1.0 mIU/ml for the respective assays. From a clinical perspective, seroprotection rates and anti-HBs geometric mean antibody concentrations for individual studies calculated with either the in-house assay or the reference assays were similar. Conclusions of individual studies were confirmed. The performance characteristics of the in-house assay are acceptable. There is no evidence that use of the new assay would lead to different clinical conclusions from the reference method.

scholarly journals Sero-survey of Hepatitis B surface antigen amongst pregnant women attending Infectious Disease Hospital Bayara, Bauchi State, Nigeria

2012 ◽  
Vol 3 (1) ◽  
pp. 10
Author(s):  
James A. Ndako ◽  
Georgebest ON. Echeonwu ◽  
Obinna O. Nwankiti ◽  
Emamuzou M. Onovoh ◽  
Alloysius U. Jah ◽  
...  
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Pregnant Women ◽  
Surface Antigen ◽  
Hepatitis B Surface Antigen ◽  
Neonatal Infection ◽  
Vaccination Schedule ◽  
Enzyme Linked Immunosorbent Assay ◽  
Public Health Importance ◽  
B Virus

Hepatitis B virus (HBV) continues to cause serious health problems in developing countries. Neonatal infection with HBV, which is often acquired during delivery, carries a high risk resulting in persistent infection. This research aims to detect the prevalence of Hepatitis B surface Antigen (HBsAg) among pregnant women in our location of study. One hundred and eighty (180) sera samples were screened among pregnant women aged 13-49, using standard enzyme-linked immunosorbent assay (ELISA) method. Structured questionnaire were administered to the subjects to obtain demographic and other relevant data. Overall result showed that 31 (17.2%) were found to be positive for HBsAg among the total subjects screened. The highest prevalence was found among those aged 20-29 with 11 (6.1%) seropositivity (x2=7.902; P=0.048). Considering occupational distribution of volunteer subjects, a high prevalence of 12 (6.7%); P<0.05 was recorded among house wives, which shows a measure of significance compared to other women screened. Furthermore, based on various risk factors subjects with history of surgery and use of unsterilized sharp instruments recorded 15 (8.3%) prevalence (P=0.233; P>0.05). How ever, women in their second trimester of pregnancy recorded a higher prevalence of 23 (12.8%):(P=0.080; P<0.05). This study therefore emphasizes the public health importance of HBV among pregnant women and equally suggests that children born to women with Hepatitis B Virus, be closely monitored for infection beyond the one and the half years of age, this also calls for a proper enlightenment on the dangers posed by the virus, while a well designed vaccination schedule is advocated among the general population.

scholarly journals Agreement Between Rapid Hepatitis B Surface Antigen Test Kit and ELISA for the Diagnosis of Hepatitis B Virus Infection in Gondar, North West Ethiopia.

2021 ◽  
Author(s):  
Mulualem Lemma ◽  
Gueshay Tsegay ◽  
Kasaw Adane
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Surface Antigen ◽  
Hepatitis B Surface Antigen ◽  
Diagnostic Methods ◽  
Enzyme Linked Immunosorbent Assay ◽  
Test Kit ◽  
B Virus ◽  
Kappa Value ◽  
Good Agreement

Abstract Background: Hepatitis B Virus is one of the major causes of global public health problems. Diagnosis of HBV is done by using ELISA and immune-chromatographic assays for detecting different serologic markers. Hepatitis B surface antigen (HBsAg) is the most frequently used serological marker employed to diagnosis HBV using Rapid Diagnostic Test (RDT) and Enzyme Linked Immunosorbent Assay (ELISA) methods. The RDT method is the most commonly used diagnostic tool in Ethiopia as well as in most African countries. Therefore assessing and knowing the diagnostic performance of the RDT is important. Method: A prospective cross sectional study was done at University of Gondar comprehensive specialized Hospital from Feb, 2017- May, 2017. Ethical clearance was obtained from School of Biomedical and Laboratory Sciences Research Ethics Committee. Permission was obtained from Blood Bank office to use blood sample collected from voluntary blood donors. HBsAg was diagnosed using RDT and ELISA methods. ELISA considered as gold-standard to the performance of RDT. Data were entered into statistical package for social sciences (SPSS) version 20 software and analysis was done by using SPSS and for sensitivity, specificity, predictive value, and likelihood ratio Medi calc software. The agreement of the methods presented assessed using kappa value. Result: Each 161 specimen was diagnosed using both ELISA (ADVANCED®) and RDT (Ecotest®). A total ELISA confirmed 41 positive specimens and 120 ELISA confirmed negative specimens were re-analyzed using RDT. The results of RDT showed only 35 positives from the total tested specimens including 29 which already positive by ELISA and RDT showing a sensitivity of 70.7% and specificity 95% with its kappa value 0.69 indicating a good agreement with ELISA.Conclusion and recommendation: Rapid Ecotest® test of HBsAg has good agreement with ELISA but low sensitivity and high false negative value, so there should be an algorithm for HBV diagnostic methods when we used a rapid test kits.

Discrepant Hepatitis B Surface Antigen Results in Pregnant Women Screened to Identify Hepatitis B Virus Infection

2014 ◽  
Vol 165 (4) ◽  
pp. 773-778 ◽  
Author(s):  
Steven L. Veselsky ◽  
Tanja Y. Walker ◽  
Nancy Fenlon ◽  
Chong-Gee Teo ◽  
Trudy V. Murphy
Keyword(s):  
Hepatitis B Virus ◽  
Virus Infection ◽  
Hepatitis B ◽  
Pregnant Women ◽  
Surface Antigen ◽  
Hepatitis B Surface Antigen ◽  
Hepatitis B Virus Infection ◽  
B Virus

Sensitivity of hepatitis B virus DNA transcription-mediated amplification testing in hepatitis B surface antigen?positive blood donations

Transfusion ◽  
2006 ◽  
Vol 46 (12) ◽  
pp. 2047-2052 ◽  
Author(s):  
Françoise Bouchardeau ◽  
Annie Girault ◽  
Annie Razer ◽  
Annabelle Servant-Delmas ◽  
Mélanie Mercier ◽  
...  
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Surface Antigen ◽  
Hepatitis B Surface Antigen ◽  
Blood Donations ◽  
Dna Transcription ◽  
Hepatitis B Virus Dna ◽  
B Virus

Enhanced production of hepatitis B surface antigen in NIH 3T3 mouse fibroblasts by using extrachromosomally replicating bovine papillomavirus vector

1983 ◽  
Vol 3 (6) ◽  
pp. 1032-1039
Author(s):  
Y Wang ◽  
C Stratowa ◽  
M Schaefer-Ridder ◽  
J Doehmer ◽  
P H Hofschneider
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Surface Antigen ◽  
Hepatitis B Surface Antigen ◽  
Bovine Papillomavirus ◽  
Mouse Fibroblasts ◽  
Antigen Gene ◽  
B Virus ◽  
Nih 3T3 ◽  
Papillomavirus Dna

We have constructed a recombinant pBR322 plasmid composed of a subgenomic transforming fragment of bovine papillomavirus DNA and the hepatitis B surface antigen gene from cloned hepatitis B virus DNA and used it for transfection of NIH 3T3 mouse fibroblasts. The transformed cells retain the plasmids in extrachromosomal form with a copy number of about 50 to 100 per cell. Expression of the hepatitis B surface antigen gene linked to bovine papillomavirus DNA is independent of its orientation relative to the bovine papillomavirus vector. Cell lines continuously secreting high amounts of hepatitis B surface antigen into the medium could be established. The antigen is released into the culture medium as 22-nm particles, having the same physical properties and constituent polypeptides as those found in the serum of hepatitis B virus-infected patients.

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