scholarly journals Semiautomated Quantification of Hepatitis B Virus DNA in a Routine Diagnostic Laboratory

2000 ◽  
Vol 7 (5) ◽  
pp. 853-855 ◽  
Author(s):  
Harald H. Kessler ◽  
Evelyn Stelzl ◽  
Elisabeth Daghofer ◽  
Brigitte I. Santner ◽  
Egon Marth ◽  
...  

ABSTRACT The Cobas Amplicor HBV Monitor test for quantitative determination of hepatitis B virus (HBV) DNA in serum has recently been introduced. To evaluate the performance of this assay in a routine diagnostic laboratory, reproducibility of results was determined with the First European Union Concerted Action HBV Proficiency Panel and the Accurun 325 HBV DNA Positive Control, Series 300. Results for 270 routine serum samples were additionally evaluated. To avoid the retesting of a large number of samples due to titers exceeding the upper limit for the linear range of the assay, sera of patients with chronic hepatitis B (CHB) were diluted prior to the assay to 10−4 in normal human plasma, which is included in the assay. The mean coefficient of variation was 22.9% for all input HBV DNAs. Of 270 routine serum samples, 182 (150 sera from transplant donors and 32 sera from patients who had recovered from CHB) tested negative. Eighty-six sera were found to be HBV DNA positive; in six sera, HBV DNA levels were found to exceed the upper limit for the linear range of the assay and had to be retested. In the remaining two sera, inhibition occurred. The semiautomated Cobas Amplicor HBV Monitor test showed sufficient reproducibility and helped in avoiding human error. The relatively narrow linear range of detection is a limitation of the new assay.

1999 ◽  
Vol 37 (9) ◽  
pp. 2793-2797 ◽  
Author(s):  
Ulrika Noborg ◽  
Annkatrin Gusdal ◽  
Eva K. Pisa ◽  
Anders Hedrum ◽  
Magnus Lindh

A highly sensitive method of quantitative analysis of hepatitis B virus (HBV) DNA in serum, the Cobas Amplicor HBV Monitor (Cobas-AM) test, was evaluated. Following a manual extraction of viral DNA, amplification, colorimetric detection, and quantitative determination are all automatically performed in the Cobas analyzer. Serially diluted samples with known HBV DNA concentrations were analyzed blindly. All samples with a virus concentration of 400 copies/ml and 83% of samples with a virus concentration of 100 copies/ml could be detected. A linear correlation between input HBV DNA and measured HBV DNA was seen in the range from 100 to 105 copies/ml. The mean coefficient of variation was 29.6% for all input levels and 18.9% for HBV DNA concentrations above 400 copies/ml. Samples with an HBV DNA level above 109 copies/ml could be reproducibly measured after predilution to 10−4 or 10−6 in negative serum; however, the level was underestimated if target DNA after dilution was still above the linear range of the assay. Quantitative results of the Cobas-AM test were interchangeable with measurements by the manual microwell plate version of Amplicor HBV Monitor (MWP-AM); the mean ratio for log Cobas-AM results/log MWP-AM results was 0.97 (standard error of the mean, 0.007) when serum samples from 153 chronic carriers were analyzed. The test should be of value for clinical assessment of chronic carriers and for monitoring the response to antiviral treatment. A limitation is the relatively narrow linear range of the assay, requiring predilution of high-titer (mainly hepatitis B e-antigen-positive) samples.


2003 ◽  
Vol 10 (4) ◽  
pp. 718-720 ◽  
Author(s):  
Fernando Lopes Gonçales ◽  
Josiane Silveira Felix Pereira ◽  
Claudia da Silva ◽  
Glaucimari Roberto Thomaz ◽  
Maria Helena Postal Pavan ◽  
...  

ABSTRACT With the use of PCR, we searched for hepatitis B virus (HBV) DNA in serum samples from 415 HBsAg-negative, anti-HBc-positive patients: 150 were blood donors, 106 had only hepatitis C virus (HCV) infection, and 159 had human immunodeficiency virus (HIV) infection (of which 88 were HCV positive and 71 were HCV negative). HBV DNA was detected in 4% of blood donors, 3.4% of HIV- and HCV-positive patients, and 24% of HCV-positive patients.


1999 ◽  
Vol 37 (9) ◽  
pp. 2899-2903 ◽  
Author(s):  
Aki Abe ◽  
Kazuaki Inoue ◽  
Takeshi Tanaka ◽  
Junko Kato ◽  
Naoki Kajiyama ◽  
...  

Quantitation of hepatitis B virus (HBV) DNA in serum is a useful method for the monitoring of HBV replication. We attempted to develop a quantitative assay system for HBV DNA that is more sensitive, accurate, and reproducible than existing systems. We detected HBV DNA by real-time detection PCR (RTD-PCR) based on Taq Man chemistry. The efficacy of this assay was evaluated by quantitatively measuring sequential levels of synthetic DNA and DNA in clinical serum samples. The detection limit of this system was as few as 10 DNA copies/reaction. A linear standard curve was obtained between 101 and 108 DNA copies/reaction. The coefficient of variation for both intra- and interexperimental variability indicated remarkable reproducibility. This system detected HBV DNA in 100% of chronic hepatitis B patients tested and never detected HBV DNA in healthy volunteers who were negative for HBV markers. These observations suggest that RTD-PCR is an excellent candidate for a standard HBV quantification method.


1999 ◽  
Vol 37 (1) ◽  
pp. 161-164 ◽  
Author(s):  
Vicky C. H. Lai ◽  
Richard Guan ◽  
Michael L. Wood ◽  
Su Kong Lo ◽  
Man-Fung Yuen ◽  
...  

A nucleic acid photo-cross-linking technology was used to develop a direct assay for the quantification of hepatitis B virus (HBV) DNA levels in serum. Cross-linker-modified DNA probes complementary to the viral genomes of the major HBV subtypes were synthesized and used in an assay that could be completed in less than 6 h. The quantification range of the assay, as determined by testing serial dilutions of Eurohep HBV reference standards and cloned HBV DNA, was 5 × 105 to 3 × 109 molecules of HBV DNA/ml of serum. Within-run and between-run coefficients of variation (CVs) for the assay were 4.3 and 4.0%, respectively. The assay was used to determine HBV DNA levels in 302 serum samples, and the results were compared to those obtained after testing the same samples with the Chiron branched-DNA (bDNA) assay for HBV DNA. Of the samples tested, 218 were positive for HBV DNA by both assays and 72 gave results below the cutoff for both assays. Of the remaining 12 samples, 10 were positive for HBV DNA by the cross-linking assay only; the 2 other samples were positive by the bDNA assay only. Twenty-eight samples had to be retested by the bDNA assay (CV, >20% between the results obtained from the testing of each sample in duplicate), whereas only three samples required retesting by the cross-linking assay. The correlation between the HBV DNA levels, as measured by the two tests, was very high (r = 0.902; P = 0.01). We conclude that the cross-linking assay is a sensitive and reproducible method for the detection and quantification of HBV DNA levels in serum.


Author(s):  
Gustaf E Rydell ◽  
Simon B Larsson ◽  
Kasthuri Prakash ◽  
Maria Andersson ◽  
Heléne Norder ◽  
...  

Abstract Background Hepatitis B virus (HBV) integration has implications for cancer development and surface antigen (HBsAg) production, but methods to quantify integrations are lacking. The aim of this study was to develop a droplet digital PCR (ddPCR) assay discriminating between circular and integrated HBV DNA, and to relate the distribution between the two forms to other HBV markers. Methods ddPCR with primers spanning the typical linearization breakpoint in the HBV genome allowed for quantification of the absolute copy numbers of total and circular HBV DNA, and calculation of linear HBV DNA. Results Analysis of 70 liver biopsies from patients with chronic HBV infection revealed that the fraction of linear HBV DNA, which includes integrations, was higher in HBeAg-negative patients than HBeAg-positive. The ratio between HBsAg and HBV DNA levels in serum correlated with the intrahepatic proportion of linear HBV DNA. Furthermore, ddPCR experiments on serum samples and experiments with nuclease indicated the contribution of encapsidated double-stranded linear DNA and replication intermediates to be limited. Conclusions The degree of integration of intrahepatic HBV DNA in the HBeAg-negative stage may be higher than previously anticipated, and integrated DNA may explain the persistence of high HBsAg serum levels in patients with low HBV DNA levels.


2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A297-A297
Author(s):  
Fu-Sheng Wang ◽  
Fanping Meng ◽  
Jiehua Jin ◽  
Yuanyuan Li ◽  
Regina Wanju Wong ◽  
...  

BackgroundWe have demonstrated the ability of Hepatitis-B-virus (HBV)-specific T cell receptor (TCR) bioengineered T cells to recognize and lyse Hepatocellular carcinoma (HCC) cells expressing HBV antigens derived from HBV-DNA integration in patients with liver transplant.1 LioCyx-M is an immunotherapeutic product composing of autologous T cells transiently modified with in-vitro transcribed mRNA encoding HBV-specific TCR. The transient TCR expression makes LioCyx -M amenable to a dose escalating posology.MethodsThe primary endpoint of this phase 1 trial is to assess the safety and tolerability of LioCyx-M in patients with advanced HBV-HCC without curative treatment options. Eligible patients were diagnosed with Barcelona clinic liver cancer stage B or C HCC (Child-Pugh < 7 points), receiving >1 year antiviral treatment prior to enrollment. These patients had matching HLA class I genotypes which present HBV encoded antigen. Peripheral blood was collected from each patient prior to each dose for LioCyx-M manufacturing. Patients received 4 escalating doses of 1×104 cells/kg, 1×105 cells/kg, 1×106 cells/kg, 5×106 cells/kg bodyweight (BW) in the first treatment cycle, each intravenously administered weekly. Patients underwent 1-month safety assessment post the 4th infusion, according to Common Terminology NCI CTCAE Version 4.0.3. If there were no dose associated toxicities, patients were eligible to continue administration of LioCyx-M at dose of 5 × 106 cells/kg BW weekly. Tumor response per RECIST 1.1 criteria and survival time were assessed.ResultsAt data cutoff (30 April 2020), eight patients were enrolled, with a median age of 53 (range: 49 - 67). These patients received a median number of 6 (range: 4 - 12) infusions of LioCyx-M. 1 patient developed Grade 3 elevations in alanine aminotransferase (ALT), gamma-glutamyl transferase (GGT), aspartate aminotransferase (AST) and bilirubin after receiving LioCyx-M at dose level of 1×105 cells/kg BW. Another patient had Grade 1 transient fever after receiving LioCyx-M at dose level 5×106 cells/kg BW in the 4th, 5th and 6th infusions. No treatment-related adverse events (trAEs) such as cytokine release syndrome or neurotoxicity were observed. No fatal trAEs were observed. The median time to progression was 1.9 months (range: 0.2 - 9.5 months). The median overall survival was 34 months (range: 3 - 38.2 months).ConclusionsThe encouraging clinical outcome and tolerable safety highlight the good benefit-risk profile of LioCyx-M. Therefore, further exploration of efficacy of LioCyx-M treatment for advanced HBV-HCC is warranted in a Phase 2 proof-of-concept clinical study.AcknowledgementsFunding: Lion TCR.Trial RegistrationNCT03899415Ethics ApprovalThe study was approved by Fifth Medical Center of Chinese PLA General Hospital’s Ethics Board, approval number R2016185DI010.ReferenceTan AT, Yang N, Lee Krishnamoorthy T, et al. Use of Expression Profiles of HBV-DNA Integrated Into Genomes of Hepatocellular Carcinoma Cells to Select T Cells for Immunotherapy. Gastroenterology 2019;156(6):1862–1876.e9.


2008 ◽  
Vol 12 ◽  
pp. e415
Author(s):  
Z.L. Wu ◽  
X.D. Lu ◽  
X.Q. Zhong ◽  
L.F. Ling ◽  
G. Lin ◽  
...  

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Oluyinka Oladele Opaleye ◽  
Adeolu Sunday Oluremi ◽  
Adetona Babatunde Atiba ◽  
Moses Olubusuyi Adewumi ◽  
Olatunji Victor Mabayoje ◽  
...  

HIV has been known to interfere with the natural history of hepatitis B virus (HBV) infection. In this study we investigate the prevalence of occult hepatitis B virus infection (OBI) among HIV-infected individuals in Nigeria. Overall, 1200 archived HIV positive samples were screened for detectable HBsAg using rapid technique, in Ikole Ekiti Specialist Hospital. The HBsAg negative samples were tested for HBsAg, anti-HBc, and anti-HCV by ELISA. Polymerase chain reaction was used for HBV DNA amplification and CD4 counts were analyzed by cytometry. Nine hundred and eighty of the HIV samples were HBsAg negative. HBV DNA was detected in 21/188 (11.2%) of patients without detectable HBsAg. CD4 count for the patients ranged from 2 to 2,140 cells/μL of blood (mean = 490 cells/μL of blood). HCV coinfection was detected only in 3/188 (1.6%) of the HIV-infected patients (P>0.05). Twenty-eight (29.2%) of the 96 HIV samples screened were positive for anti-HBc. Averagely the HBV viral load was <50 copies/mL in the OBI samples examined by quantitative PCR. The prevalence of OBI was significantly high among HIV-infected patients. These findings highlight the significance of nucleic acid testing in HBV diagnosis in HIV patients.


2004 ◽  
Vol 48 (6) ◽  
pp. 2199-2205 ◽  
Author(s):  
Radhakrishnan P. Iyer ◽  
Yi Jin ◽  
Arlene Roland ◽  
John D. Morrey ◽  
Samir Mounir ◽  
...  

ABSTRACT Several nucleoside analogs are under clinical development for use against hepatitis B virus (HBV). Lamivudine (3TC), a nucleoside analog, and adefovir dipivoxil (ADV), an acyclonucleotide analog, are clinically approved. However, long-term treatment can induce viral resistance, and following the cessation of therapy, viral rebound is frequently observed. There continues to be a need for new antiviral agents with novel mechanisms of action. A library of more than 600 di- and trinucleotide compounds synthesized by parallel synthesis using a combinatorial strategy was screened for potential inhibitors of HBV replication using the chronically HBV-producing cell line 2.2.15. Through an iterative process of synthesis, lead optimization, and screening, three analogs were identified as potent inhibitors of HBV replication: dinucleotides ORI-7246 (drug concentration at which a 10-fold reduction of HBV DNA was observed [EC90], 1.4 μM) and ORI-9020 (EC90, 1.2 μM) and trinucleotide ORI-7170 (EC90, 7.2 μM). These analogs inhibited the replication of both strands of HBV DNA. No suppression of HBV protein synthesis or intracellular core particle formation by these analogs was observed. No inhibition of HBV DNA strand elongation by the analogs or their 5′-triphosphate versions was apparent in in vitro polymerase assays. Although the exact mechanism of action is not yet identified, present data are consistent with an inhibition of the HBV reverse transcriptase-directed priming step prior to elongation of the first viral DNA strand. In transient-transfection assays, these analogs inhibited the replication of 3TC-resistant HBV. Synergistic interactions in combination treatments between the analogs and either 3TC or ADV were observed. These compounds represent a novel class of anti-HBV molecules and warrant further investigation as potential therapeutic agents.


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