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1.
The usefulness of fully automated chemiluminescent microparticle immunoassay (Architect HBsAg QT) for monitoring serum levels of hepatitis B virus (HBV) during antiviral therapy remains unclear. Using this assay, hepatitis B surface antigen (HBsAg) was measured in 20 patients with chronic hepatitis B before and during lamivudine treatment. At the start of therapy, 12 patients had detectable hepatitis B e antigen (HBeAg) and 8 did not. The median serum HBV DNA level and HBsAg concentration (25th-75th centile) were 7.2 (6.1-7.8) log genome equivalents/ml and 3,932 (1,585-12,330) IU/ml, respectively. The HBsAg concentration was significantly higher in HBeAg positive than in HBeAg negative patients (P=0.031). There was a significant correlation between the HBsAg concentration and HBV DNA level (r=0.490, P=0.027). The HBsAg concentration negatively correlated with patient age (r=-0.395, P=0.085). After the start of lamivudine therapy, HBV DNA levels fell rapidly in all patients. Serum HBsAg concentrations also fell in most patients, but to a lesser extent. When drug-resistant variants emerged, serum HBsAg usually increased before biochemical breakthrough. Although HBV DNA was elevated persistently after the emergence of drug-resistant variants, the increase in HBsAg was transient. In some patients, the increase in HBsAg preceded the increase in HBV DNA. Monitoring of serum HBsAg concentrations with the use of Architect HBsAg QT, in addition to measurement of HBV DNA levels, is helpful for evaluating the response to lamivudine treatment and for the early detection of drug-resistant strains.  相似文献   

2.
BackgroundHBsAg quantitation may be useful for managing patients with hepatitis B virus (HBV) infection.ObjectivesWe explored the clinical implications of HBsAg quantitation for patients with HBsAg levels >250 IU/ml (Abbott Diagnostics).Study designTwo hundred and thirty-three HBV-infected patients comprising 29 immune tolerance cases, 49 treatment-naïve HBeAg-positive chronic hepatitis B (CHB) cases, 91 inactive HBV carrier cases, and 64 treatment-naïve HBeAg-negative CHB cases were analyzed. HBsAg was quantified by the Architect HBsAg assay (Abbott Diagnostics) after a 1:500 automated dilution.Results and conclusionsHBsAg (log 10 IU/ml) was established for immune tolerance (4.50 ± 0.43), HBeAg-positive CHB (4.17 ± 0.66), inactive HBV carrier (3.32 ± 0.44), and HBeAg-negative CHB (3.23 ± 0.40); (p = 4.92 × 10−35). No significant difference was observed between inactive HBV carrier and HBeAg-negative CHB (p = 0.247). The proportions of HBsAg <2000 IU/ml for inactive HBV carrier and HBeAg-negative CHB were 51.6% and 59.3%, respectively (p = 0.341). Positive correlations between HBsAg and HBV DNA were observed for immune tolerance (p = 1.23 × 10−4) and HBeAg-positive CHB (p = 0.003), but not for HBeAg-negative CHB (p = 0.432). A negative correlation between HBsAg and age was observed for immune tolerance (p = 0.030), HBeAg-positive CHB (p = 0.016), and inactive HBV carrier (p = 0.001), but not in HBeAg-negative CHB (p = 0.249). No significant differences between HBsAg and ALT for HBeAg-positive (p = 0.338) or HBeAg-negative CHB (p = 0.564) were observed. For patients with HBsAg quantitation >250 IU/ml, HBsAg may reflect HBV DNA replication for HBeAg-positive cases. HBsAg is not a suitable marker for evaluating hepatitis activity and distinguishing between cases of HBeAg-negative CHB and inactive HBV carrier state.  相似文献   

3.
Hepatitis B virus (HBV) DNA was assayed using the polymerase chain reaction in serum samples of 116 hepatitis B surface antigen (HBsAg) carriers, including 30 positive for hepatitis B e antigen (HBeAg) and 86 negative for HBeAg. In the HBeAg-positive group, all were positive for HBV DNA. In the HBeAg-negative group, 80.2% were positive for HBV DNA (80.0% in the healthy carrier group, 90.0% in the chronic active liver disease group, and 69.2% in patients with cirrhosis). This study indicated that every HBeAg-positive carrier as well as the majority of HBeAg-negative carriers were infectious and, in the latter group, that viral replication is most active in patients with chronic active liver disease.  相似文献   

4.
A 30-year-old surgical resident was admitted to the hospital with symptoms of acute hepatitis; two days later he became comatose. Hepatitis B surface antigen had been detected in his serum two days prior to admission, but it was not detected at any time thereafter. Hepatitis B e antigen, antibody to hepatitis B core antigen, and antibody to hepatitis B surface antigen were detected using sensitive radioimmunoassays at admission. Titers of antibody to hepatitis B core antigen increased over the next five weeks. Clearance of hepatitis B e antigen and subsequent appearance of antibody to hepatitis B e antigen accompanied clinical improvement and recovery. This unusual case documents that hepatitis B surface antigen can become undetectable during the course of fulminant hepatitis B and indicates the importance of tests for other serologic markers of hepatitis B virus in the evaluation of hepatitis B surface antigen-negative fulminant hepatitis.  相似文献   

5.
To investigate the characteristics of cytokines in patients with different HBV infection status and their correlation with HBV DNA, HBsAg, and HBeAg levels. Peripheral blood samples were collected from patients with chronic HBV infection in immune tolerance phase (IT), HBeAg-positive chronic hepatitis B (CHB), and acute hepatitis B (AHB) groups, and levels of cytokines were detected by Luminex technique, and analyzed by FLEXMAP 3D analyzer. The correlation between cytokines and HBV DNA load, HBsAg, HBeAg, and alanine aminotransferase (ALT) level in patients with chronic HBV infection was analyzed. In total 312 subjects (184 males and 128 females) were enrolled in the study. There were significant differences among IT, CHB, and AHB groups in Flt-3L value (P = .003; H = 12.312), IFN-γ (P = .001; H = 11.723), IL-10 (P = .001; H = 18.736), IL-17A ((P = .001; H = 12.735), and TGF-β1 (P = .001; Z = 48.571). IFN-α2 levels in CHB group were significantly higher than those in IT and AHB groups (15.24 vs 35.78 pg/mL, P = .000; Z = 3.727; 13.88 vs 35.78 pg/mL, P = .024; Z = −2.258. In CHB group, the levels of HBsAg and ALT were positively correlated with the levels of IL-10 (r = .173; P = .006; r = 0.176; P = .006, respectively), while HBeAg level was positively correlated with the IFN-α2 level (r = .153; P = .016). In AHB group, the HBsAg level was positively correlated with Flt-3L, IFN-α2, IL-10, and IL-6 (r = .402; P = .023; r = .436; P = .016; r = .524, P = .002; r = .405; P = .022, respectively). HBeAg level was positively correlated with IFN-γ and IL-17A levels (r = .400; P = .023; r = .373; P = .036, respectively), and ALT level was positively correlated with IL-6 levels (r = .367; P = .039). In either AHB or CHB group, HBV DNA load was only related to TGF-β level (r = .493; P = .004; r = −.218, P = 0.009 respectively). The correlation between Flt-3L and HBsAg (F = 7.422; P = .007); IL-17, IL-6, and HBeAg (F = 5.757; P = .017; F = 6.156; P = .014) were statistically significant. There was significant correlation between TGF-β2 and HBV DNA (F = 11.795; P = .001), and between ALT and HBsAg, HBV DNA (F = 26.089; P = .000; F = 4.724; P = .031). HBsAg, HBeAg, and HBV DNA were correlated with cytokines and ALT in patients with HBV infection. The level of IFN-α2 was significantly higher in patients with CHB. HBV DNA load was only correlated with the level of TGF-β in acute or CHB.  相似文献   

6.
Purpose: Hepatitis B surface Antigen (HBsAg) is the hallmark in diagnosing hepatitis B virus (HBV) infection. In India many commercial assays are available for detection of HBsAg but very few can measure it quantitatively. The present study presents the comparative evaluation of two methods and their correlation with serum HBsAg in chronic hepatitis B (CHB) patients. Materials and Methods: Consecutive patients of CHB were included and there HBsAg levels were measured by two methods: (i) Elecsys, Roche Diagnostics, a qualitative assay and (ii) Architect, Abbott Diagnostics, a quantitative assay. The HBV DNA was measured by real-time polymerase chain reaction (qPCR). Results: Total of 136 patients were included in the study and there was a significant overall correlation between both the assays (correlation coefficient [r] = 0.83; P < 0.001). Assays correlated well with each other across all subgroups of CHB: treatment naïve (r = 0.73; P < 0.001, n = 32), on treatment (r = 0.56; P < 0.05, n = 104), hepatitis Be (HBe) antigen positive (r = 0.67; P < 0.001, n = 62) and anti-HBe positive (r = 0.61; P < 0.05, n = 74) group. On correlation with serum HBV DNA, Architect assay demonstrated good correlation (r = 0.73; P < 0.001, n = 136) as compared to the Elecsys assay (r = 0.27; P = 0.068, n = 136). Architect HBsAg QT assay (A1) also correlated well with HBV DNA in the treatment naïve group (r = 0.69; P < 0.001, n = 32). Conclusions: Our study hence proved that both the assays are comparable and a simple qualitative assay with in-house modification can be used easily for quatitation of HBsAg in clinical samples.  相似文献   

7.
Changes in two novel HBV serological markers, linearized hepatitis B surface antigen (HQ-HBsAg) and hepatitis B core-related antigen (HBcrAg), in the natural history of chronic hepatitis B (CHB) have not been well characterized. Serum HQ-HBsAg and HBcrAg levels of 404 Asian treatment-naïve CHB patients were analysed in a cross-sectional manner. Patients were categorized into five groups: immune tolerant (IT group, n = 52), immune clearance (IC group, n = 105), hepatitis B e antigen (HBeAg)-negative hepatitis (ENH group, n = 97), HBeAg-negative quiescent group (ENQ group, n = 95) and CHB with hepatitis B surface antigen (HBsAg) seroclearance (SC group, n = 55). HQ-HBsAg and HBcrAg were measured and correlated with HBV DNA, HBsAg, HBV genotype and clinical parameters. HQ-HBsAg showed good correlation with HBsAg, especially in the ENQ group (r = 0.874, p <0.001). Correlation of HQ-HBsAg with HBV DNA was less prominent and weakest in the ENH group (r = 0.268, p 0.008). HBcrAg correlated best with HBV DNA in the ENQ group (r = 0.537, p <0.001). In the ENQ group, 42.1% of patients had undetectable HBcrAg; this subgroup of patients, when compared with those with detectable HBcrAg, had significantly lower median HBV DNA (3.17/4.48 log IU/mL, p <0.001) and HBsAg (5.05/5.96 log mIU/mL, p <0.001) levels. Forty per cent of the SC group patients had detectable HQ-HBsAg and/or HBcrAg up to 42 months after HBsAg seroclearance. When comparing anti-HBs positivity and median time after HBsAg seroclearance in the SC group with and without detectable HQ-HBsAg/HBcrAg, there was no significant difference (22.7% and 36.4%, respectively, p 0.284, and 76.5 and 93.2 months, respectively, p 0.245). HQ-HBsAg and HBcrAg showed unique patterns of distribution throughout the five disease phases of CHB, including high detectability rates after HBsAg seroclearance, opening up different possibilities for their applicability.  相似文献   

8.
Occult hepatitis B virus (HBV) infection is characterized by the presence of HBV DNA while the HBV surface antigen (HBsAg) remains undetectable. The HBV genomes in five asymptomatic blood donors with occult HBV infection and low viremia (<10 to 1,000 HBV DNA copies/mL, genotype D) were studied. An unusually large number of amino acid mutations was present in the immunodominant a-determinant of HBsAg (respectively 3, 6, 7, 10, and 10 mutations). Comparison of the HBV genomes in two donors to a consensus HBV genotype D sequence showed a most prominent hotspot of genetic variation in HBV nucleotides 480-570, encoding the HBsAg a-determinant. The phylogenetic comparison of separate donor HBV genes to the HBV genes of 11 reference strains (genotypes A-H) showed the donor HBV surface genes to form an outgroup, while the HBV polymerase, core and X genes closely cluster with the HBV genotype D reference strain. Maybe the HBV strains in this study represent a natural end-stage of seemingly cleared HBV infection, in which HBV maintains a low level of possibly non-infectious replication, after sacrificing its immunologically offending surface antigen, thus avoiding final clearance by the immune system.  相似文献   

9.
Eleven male fulminant hepatitis (FH) patients (mean age: 47.7 +/- 16 years) positive for hepatitis B surface antigen (HBsAg) but negative for IgM antibody to hepatitis B core antigen (IgM anti-HBc) were admitted consecutively to the Athens Hospital for Infectious Diseases between May 1981 and November 1983. Because of the absence of IgM anti-HBc, determined by an enzyme immunoassay, these patients were considered to be HBsAg carriers with a superimposed acute hepatitis. Three of the 11 patients received immunosuppressive chemotherapy during the six months before the onset of the acute hepatitis. None of the patients was homosexual or a drug addict. Infection with hepatitis A virus (HAV), hepatitis B virus (HBV), or hepatitis delta virus (HDV) was detected with serologic markers and/or molecular hybridization techniques. Fulminant hepatitis was attributed to spontaneous reactivation of chronic hepatitis B in four patients, chemotherapy-induced reactivation of chronic hepatitis B in three patients, HDV superinfection in one patient and possible superinfection by non-A, non-B agent(s), HDV, or HDV-like agents in three patients. Reactivation of chronic hepatitis B was an important cause of apparent acute hepatitis in heterosexual male HBsAg carriers from an area with a high prevalence of HBV infection.  相似文献   

10.
Purpose: The hallmark of chronic hepatitis B (CHB) infection is the presence of hepatitis B surface antigen (HBsAg) positivity for at least 6 months. Recently, serum levels of HBsAg have been compared with serum HBV DNA as a surrogate marker to monitor CHB patients. However, data correlating these two markers are scarce. Hence, the present study was done to correlate HBV DNA with HBsAg in CHB patients. Materials and Methods: Consecutive patients of CHB were included. HBV DNA was measured by real-time polymerase chain reaction (PCR). Serum HBsAg was measured by Architect HBsAg. Results: Of the 198 patients enrolled, 166 fulfilled the inclusion criteria (mean age 43 ± 14 years, 87% males) and the median HBV DNA was 1.7 × 103 (range 6.0–1.1 × 108) IU/ml. Median HBsAg was 8.7 × 103 (range 5.0–3.2 × 105) IU/ml. Overall correlation between HBV DNA and HBsAg was weak but significant (Spearman ρ = 0.443, P < 0.01). Correlation in HBe antigen-positive group was better (ρ = 0.402, P < 0.01) in comparison to HBe antigen-negative group (ρ = 0.193 P = 0.05). Good correlation existed in treatment-naïve group (ρ = 0.538, P < 0.01). Correlation was regardless of normal or raised alanine transaminase (ALT). Eighty (48%) patients had high HBV DNA (≥2000 IU/ml). Correlation in high DNA group was significant (P < 0.01). The best cut-off of HBsAg for diagnosing high DNA is 3.36 ×103 IU/ml. Conclusions: Serum HBsAg correlates with HBV DNA in CHB patients, especially in high serum HBV DNA, HBe antigen-positive and treatment-naïve group. HBsAg levels can be used for predicting high serum HBV DNA levels.  相似文献   

11.
In chronic hepatitis B, quantitative measurements of hepatitis B surface antigen (HBsAg) have been studied increasingly using stored sera to determine its usefulness in disease management. However, the stability of stored HBsAg levels has not been established. The current study determines prospectively the stability of HBsAg levels in sera stored for 1 year. Fresh sera from 105 samples were divided into 5 aliquots. The first aliquot was used to determine HBsAg at the time of blood sampling. The remaining four aliquots were stored at -20°C and thawed at 3, 6, 9, and 12 months to determine the HBsAg levels. HBsAg was measured by adopting the research protocol using the Elecsys HBsAg II assay. At baseline, age and HBV DNA showed a significant correlation with HBsAg levels (r = -0.291, P = 0.003 and r = 0.256, P = 0.003, respectively). There was no overall significant difference observed between the HBsAg levels measured at the different time points. There was high correlation between each consecutive time points from baseline to 3 months, 3-6 months, 6-9 months, and 9-12 months (r = 0.991, 0.987, 0.989, 0.993, respectively, all P < 0.001). The overall log difference in HBsAg levels between baseline and at 12 months was 0.03 (range, -0.29 to 0.85), with over 99% of samples showing no significant change (defined as >1 log) after 12 months. In conclusion, HBsAg levels remained stable in stored frozen sera for 12 months without significant changes, and could be used to quantify HBsAg accurately.  相似文献   

12.
PURPOSE: Different stages of hepatitis B virus (HBV) infection can be defined by serum HBV DNA levels. This study attempts to (1) investigate serum HBV DNA levels in inactive carriers and patients with chronic HBV (CHB) infection and (2) define cut-off value between inactive carriers and HBeAg (precore antigen of HBV) negative CHB patients in Indian population. METHODS: One hundred and forty samples encompassing 42 inactive HBsAg carriers and 98 CHB patients (53 HBeAg-positive and 45 HBeAg-negative) were analysed. Serum HBV DNA levels were determined employing an in-house competitive polymerase chain reaction (cPCR) assay. RESULTS: The HBeAg-positive patients were found to have the maximum median HBV DNA load, which was significantly higher than the HBeAg-negative ones (median; 1.25 x 10(8) vs. 2.30 x 10(5) copies/mL ; P<0.05). Interestingly, the latter group has significantly higher HBV DNA levels than the inactive carriers (median; 2.30 x 10(5) vs. 4.28 x 10(3) copies/mL; P<0.05). The 2.5 x 10(4) copies/ml HBV DNA levels were optimal for discriminating CHB patients (HBeAg-negative) from inactive carriers with 75.6 and 78.6% sensitivity and specificity, respectively. CONCLUSIONS: Despite the extensive overlapping of HBV DNA levels in inactive carriers and HBeAg negative CHB patients, 2.5 x 10(4) copies/mL is the most favourable cut-off value to classify these individuals and would be imperative in the better management of this dreadful disease.  相似文献   

13.
14.

Background and objectives

Little is known about hepatitis B surface antigen (HBsAg) level during the natural course of hepatitis B virus (HBV) infection. The aims of this study were to determine the HBsAg titer in the different phases of HBV infection and to evaluate for the presence of a correlation between HBsAg titers and HBV DNA levels.

Study design

272 HBV patients were analyzed in a cross-sectional study. The patients were classified into 4 categories: immune tolerant phase (IT, n = 9), immune clearance phase (IC, n = 26), low-replicative phase (LR, n = 131), and HBeAg-negative hepatitis (ENH, n = 106).

Results

Median HBsAg titers were different between each phase of CHB (p < 0.001): IT (4.31 log10 IU/ml), IC (4.42 log10 IU/ml), LR (3.32 log10 IU/ml) and ENH (3.71 log10 IU/ml). Correlation of HBsAg and HBV DNA was strong in IT patients (r = 0.74) and the whole group (r = 0.83), moderate in the ENH phase (r = 0.44) and poor in the IC (r = 0.14) and the LR phases (r = 0.080).

Conclusions

This large study demonstrates that in HBV patients, HBsAg levels are significantly different in the different stages of the disease. A correlation between serum HBV DNA and HBsAg titers does not exist except in the IT and ENH phases. Three other studies have addressed the same issue on different genotypes and we notice that there is no concordance between the 4 studies. This leads to conclude that measurement of HBsAg level, for the time being, will not replace the serum HBV DNA as a marker of replication.  相似文献   

15.
Three hepatitis B surface antigen (HBsAg) preparations were compared: purified intact 22-nm HBsAg particles; HBsAg-derived, sodium dodecyl sulfate (SDS)-denatured P25 + GP30 polypeptide pool; and nondenatured P25 + GP30 micelles. The micelles had the same polypeptide composition as the P25 + GP30 pool. The immunogenicity in mice of each preparation, administered either in saline suspension or adsorbed to aluminum gel, was compared. The SDS-denatured polypeptides were less immunogenic than intact HBsAg particles, whereas the micelles were more immunogenic. High anti-HBs titers were observed in mice immunized with micelle preparations in either saline suspension or adsorbed to aluminum gel for as long as 200 days after a booster inoculation, administered 26 days after the primary dose.  相似文献   

16.
BackgroundHBsAg is the most important marker for laboratory diagnosis of HBV infection. Validation and quality control of HBsAg tests requires International Standards (IS). Recently the 2nd IS was replaced by the 3rd IS. Both IS are made from plasma-derived hepatitis B vaccines, but production and geographical origin are different.ObjectiveCharacterization of the HBsAg in the source material (SM) for the 3rd IS and comparison with the 2nd IS and native HBsAg.Study designThe SM was analyzed using solid-phase immunoassays, quantitative immune electrophoresis, ultracentrifugation, immunoblotting and HBV DNA sequencing.ResultsThe plasma-derived HBsAg of the SM originated from at least two different HBV strains, both of subgenotype (sgt) B4, typical for Vietnam. The HBsAg subtype was heterogeneous with ayw1 and adw2. The HBsAg concentration was 23,700 IU/ml as determined by solid-phase immunoassay; immune electrophoresis calibrated with sgt B2 revealed a concentration of 24,500 IU/ml while calibration with sgt D1 provided lower values. Proteins in the SM are heterogeneous in size containing only traces of preS. The protein subunits are partially cross-linked.ConclusionsThe antigenicity of the 3rd IS is suitable for HBsAg calibration in laboratory tests. In contrast to the 2nd IS, the 3rd IS is representative for a highly endemic region. Similar to the 2nd IS and different from native HBsAg, preS domains are depleted, protein subunits are partially cross-linked and the HBsAg particles are partially aggregated in the 3rd IS. The HBV subgenotype differences between the two IS may lead to variations in different quantitative assays.  相似文献   

17.
Monoclonal anti-idiotypic antibodies to HBsAg were screened by immunofluorescence for the presence of a subset behaving as the internal image of the original antigen. We describe the technique and the criteria fulfilled to establish that 2/6 monoclonals studied act as the internal images of the a determinant of hepatitis B surface antigen.  相似文献   

18.
Hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) is responsible for viral persistence. This study aimed to investigate the serum surrogate markers for cccDNA and to evaluate the intrahepatic viral events associated with disease activity in HBeAg‐negative chronic hepatitis B patients. Thirty‐three treatment‐naïve patients with a negative HBeAg who had a liver biopsy were studied. Active disease was defined as a serum alanine aminotransferase >40 IU/L and a serum HBV DNA >10,000 copies/ml. This study showed significant correlation between serum HBV DNA and both log cccDNA (r = 0.41, P = 0.018) and log total intrahepatic HBV DNA (r = 0.71, P < 0.0001). No significant correlation was observed between serum HBsAg and log cccDNA (P = 0.15) or log total intrahepatic HBV DNA (P = 0.97). Fourteen and 19 patients had inactive and active disease, respectively. The median log cccDNA and log total intrahepatic HBV DNA (copies/106 cells) were significantly higher in patients with active disease compared with those with inactive disease (4.11 vs. 3.53, P = 0.03 and 5.46 vs. 4.64, P < 0.001, respectively). The HBV replicative efficiency, defined as the ratio of serum HBV DNA to cccDNA, was approximately 20% higher in patients with active disease. No significant difference was observed in the HBsAg levels and the ratio of serum HBsAg to cccDNA between the two groups. In conclusion, serum HBV DNA, but not HBsAg, reflects the amount of cccDNA and the replication efficiency of HBV in patients with HBeAg‐negative chronic hepatitis B. J. Med. Virol. 82:1494–1500, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   

19.
A modification of the highly sensitive method of electrophoresis-precipitation in polyacrylamide gel for the detection of virus hepatitis B antigen (HBsAg) and antibodies against it is described. The method completely preserves the specificity of immunodiffusion in gel, but is 1000–2000 times more sensitive for the detection of HBsAg. The method has given good results with the sera of patients with various diseases. It detects HBsAg more efficiently than other methods used previously.Scientific Experimental-Production Group, Laboratory of Cellular Immunity, N. F. Gamaleya Institute of Epidemiology and Microbiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR O. V. Baroyan.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 4, pp. 508–509, April, 1977.  相似文献   

20.
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