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In this report we evaluate the human immune response to hepatitis B surface antigen (HBsAg) following remote infection with hepatitis B virus (HBV). HBsAg-reactive lymphocytes can be readily demonstrated in the peripheral blood of individuals with established immunity following infection with HBV.In vitro stimulation with small doses of plasma-derived HBsAg, yeast-derived HBsAg (S region) or pre-S2 peptide will induce specific IgG to HBsAg (anti-HBs) in the absence of a polyclonal increase in total IgG. The pre-S2 peptide will stimulate, in a T cell-dependent fashion, thein vitro production of anti-HBs with specificity for the S domain. This anti-HBs production is mediated by pre-S2-stimulated soluble T-cell factors. Peripheral blood mononuclear cells from individuals with established immunity proliferate to the yeast-derived HBsAg but not to the plasma-derived HBsAg or pre-S2 peptide. The chronic HBsAg carriers do not produce anti-HBs following stimulation with HBsAg regardless of the source or component of antigen used. Different study protocols failed to demonstrate HBsAg-specific responses in the peripheral blood mononuclear cells of chronic carriers.  相似文献   

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Seventy five patients with acute and chronic active hepatitis (CAH) were studied by indirect immunofluorescence with monoclonal antibodies for the presence of hepatitis B surface antigen (HBsAg) on peripheral blood mononuclear cells (PBMC). The viral surface antigen was detected in the PBMC of all the patients with hepatitis B virus (HBV)-induced CAH and in acute patients with more than 2 months of evolution. No HBsAg was detected in the samples obtained from 12 normal controls or from 14 non-A, non-B CAH patients. Analysis of PBMC subsets revealed that HBsAg was present in non-T cells; dual fluorescence studies showed HBsAg on surface Ig-positive lymphocytes. The binding of anti-HBs monoclonal antibodies was higher than that of a goat anti-HBs serum, and the highest reactivity was observed with an antibody against the pre-S(2)-region sequence. Both HBsAg and hepatitis B core antigen (HBcAg) were also detected in lysates of PBMC by dot blot analysis.  相似文献   

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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   

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目的制备抗乙型肝炎表面抗原(hepatitis B surface antigen,HBsAg)的单克隆抗体,检测单克隆抗体与15种变异HBsAg的反应模式。用筛选出的单抗建立快速检测变异HBsAg的ELISA实验方法,并做初步评价。方法用中国乙型肝炎病毒感染者血清中分离的HBsAg免疫BALB/c小鼠,通过杂交瘤细胞融合技术制备抗-HBs单克隆抗体。检测不同单克隆抗体与野生及变异HBsAg的反应性。筛选出两种可以较好识别变异HBsAg的单克隆抗体McAb2和McAb3,建立两种抗体ELISA检测HBsAg的方法。结果制备了14株抗-HBs单抗。经过初筛,有4种可以较好识别包括G145R在内的大多数变异HBsAg。优化了McAb2和McAb3检测HBsAg的条件,检测HBsAg的灵敏度较好,检测变异HBsAg的能力优于2种现行国产HBsAg检测试剂盒。结论用本实验制备的单抗可以很好地识别包括G145R在内的大多数变异HBsAg。  相似文献   

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目的 探讨慢性乙型肝炎患者HBsAg水平与肝脏炎症和纤维化的关系.方法 301例确诊为慢性乙型肝炎的患者纳入研究,同时进行肝脏活检术检查和生物化学、铁蛋白、血清HBsAg、HBV DNA定量检测.Spearman等级相关分析血清HBsAg水平与肝脏炎症分级和纤维化分期间的关系;logistic回归分析法分析相关指标的诊断意义,受试者工作曲线法评价血清HBsAg水平预测肝脏炎症分级和纤维化分期的准确性.结果 体质量指数、年龄、性别、基因型和家族史对CHB患者肝脏炎症和纤维化无明显影响(P<0.05).AST、ALT随着炎症、纤维化进展而升高,差异具有统计学意义(x2=71.193、96.344、47.847、63.981;P =0.000、0.000、0.000、0.000).纤维化为S4时,HBV DNA明显下降(x2=33.322,P=0.000).HBsAg水平随着炎症和纤维化程度加重而逐步下降(x2=68.173,15.719;P =0.000,0.000).HBsAg水平预测≤G3和≤S3的曲线下面积分别为0.732和0.793,特异度分别为0.778、0.891,灵敏度依次为0.685、0.633.结论 中国CHB患者HBsAg水平随着肝脏炎症分级和纤维化分期程度加重而逐渐下降.血清HBsAg水平对CHB患者肝脏炎症≤G3和纤维化≤S3的预测具有较高的特异性,且对纤维化的预测优于炎症.  相似文献   

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Amino acid changes within the major antigenic determinant of the hepatitis B virus (HBV) surface antigen (HBsAg) may modify eventually the antigenic properties of the protein and may have impact on the sensitivity of diagnostic assays. Modifications in the design of an assay can, however, improve significantly its ability to detect HBV mutants. One hundred forty‐seven clinical samples containing HBsAg variants, and 54 supernatants of cells expressing recombinant HBsAg mutants were tested by two generations of a commercial HBsAg test (Enzygnost® HBsAg 5.0 and 6.0, Siemens Healthcare Diagnostics Products, Marburg, Germany), and the results were compared. A significant improvement was demonstrated for the second test by comparing the mean and individual sample/cut‐off values, as well as by the detection of several samples displaying amino acid changes in residues 120 and 145 of the HBsAg which were recorded as negative by the former test. The results showed that modifications in design of the assay improved considerably the ability of the test to detect HBsAg mutants, and that difficulties in detecting such HBV variants should not be expected with the routine use of the test in diagnostic laboratories and in blood transfusion centers. J. Med. Virol. 83:95–100, 2011. © 2010 Wiley‐Liss, Inc.  相似文献   

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Over a seven-year period, we monitored 221 patients with chronic hepatitis from two medical centers. By using the counterelectrophoresis (CEP) test to detect the presence of HBsAg and anti-HBc, or both, we established that 87.7% of them had hepatitis B infection. Serum specimens originally found negative for HBsAg by CEP were further tested by reversed passive hemagglutination (RPH), and those originally found negative for anti-HBc by CEP were further tested by radioimmunoassay (RIA). Five patients were anti-HBc-positive and HBsAg-negative. No sex predominance was observed, but HBsAg incidence increased with increasing age. The HBeAg antigen was detected in 46.8% of the 161 cases tested for it; the most frequent subtype found was adw (63.7%). The present findings indicate that HBV infection largely contributes to the development of chronic hepatitis in Argentinian patients.  相似文献   

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Understanding the prevalence and diversity of HBsAg variants in a population is fundamental to assay design and planning vaccination programs. It has been shown that mutations within the S gene, caused by selection or natural variation, can lead to false‐negative results in assays for HBsAg, or have clinical implications, such as evading anti‐HBV immunoglobulin therapy or vaccine‐induced immunity. The region of HBsAg where most of these mutations occur is known as the major hydrophilic region (MHR). The aim of this study was to determine the prevalence and mutational patterns of MHR mutations in patients with chronic hepatitis B, and their correlation with patient characteristics, viral factors and antiviral therapy. The study comprised 164 plasma samples from patients with chronic hepatitis B, of which, 34.8% were on long‐term lamivudine monotherapy. Direct sequencing of part of the S/pol gene was used for identification of HBsAg mutations, HBV genotypes, subgenotypes and HBsAg subtypes. The overall frequency of MHR mutations was 22.6%, but it varied significantly between untreated and treated patients (16.8% vs. 33.3%). The most frequent substitution was at position 120 (9.1%) whereas the most common vaccine‐escape position, 145, was affected in 1.8% of isolates. The presence of MHR mutations was correlated with genotype D, subgenotype D3, and ayw2/ayw3 HBsAg subtypes and to older age (>40 years). It is concluded that natural viral variability present in a geographical region, duration of infection, and antiviral therapy are among the major factors associated with the occurrence of MHR mutations. J. Med. Virol. 82: 1160–1167, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   

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乙型肝炎核酸疫苗NV—HB/s肌注小鼠后HBsAg的表达和抗 …   总被引:3,自引:0,他引:3  
目的 研究乙型肝炎核酸疫苗肌注小鼠后在体内的表达及小鼠体液免疫应答的规律,同时观察接种局部组织的病理变化。方法 以乙型肝炎核酸疫苗NV-HB/s肌注小鼠,然后定期分批处死,采集肌注局部组织检测HBsAg(ABC免疫组化法),采集外周血标本检测HBsAg和抗-HBs(ELISA法0,并常规病理检查。  相似文献   

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BackgroundHepatitis B surface antigen (HBsAg) clearance during chronic hepatitis B (CHB) infection is associated with improved long-term clinical outcome, so is considered an important therapeutic goal in CHB. Studies have shown that serum HBsAg quantification during, and at end of, treatment may predict long-term HBsAg loss.ObjectivesPerformance comparison of the qualitative Elecsys HBsAg II assay using a quantitative research protocol and an established quantitative HBsAg assay.Study designA dilution algorithm was developed for the Elecsys HBsAg II assay to allow quantification of HBsAg levels; this was used to measure HBsAg levels in a range of samples including sera from patients infected with different HBV genotypes, HBV mutants, and longitudinal samples from patients undergoing antiviral treatment. Results were compared with those from the quantitative Architect HBsAg assay.ResultsThere was significant overall correlation between Elecsys and Architect assays (correlation coefficient [r] = 0.97; p < 0.001). HBsAg levels measured with both assays correlated well in all phases of infection (r = 0.80–0.96), across all genotypes tested (HBV genotype A, r = 0.89; HBV genotype D, r = 0.97), and in samples with lamivudine-resistant mutations (r = 0.94). Bland–Altman analysis showed only minor discordance between assays in different phases of chronic HBV-infection (3.8–5.1%). This strong correlation was also present for sera with lower HBsAg concentrations. On-treatment HBsAg levels were similar when measured with either assay.ConclusionsUsing a simple dilution algorithm, the quantitative Elecsys HBsAg II assay reliably determined serum HBsAg levels in a wide range of samples, and showed very high correlation with the Architect HBsAg assay.  相似文献   

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目的 探讨乙型肝炎病毒标志物在直肠癌患者人群中的具体情况,以及这部分人群中乙型肝炎病毒性标志物和Dukes分期间的相关性.方法 对2010年-2013年期间的68例直肠癌患者临床资料进行回顾性分析,所有患者均经过病理的确诊并进行了Dukes分期.结果 纳入的68例直肠癌患者其乙型肝炎病毒表面抗原的阳性率为5.88%,要低于普通健康人群.不同Dukes分期的直肠癌患者,其乙型肝炎病毒标志物阳性率相似,组间差异无统计学意义(P>0.05).结论 HBsAg的阳性可能是免于直肠癌发生的一个保护因素,另外,Dukes分期和是否感染乙型肝炎病毒不存在相关性.  相似文献   

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目的 探讨乙型肝炎表面抗原(HBsAg)和表面抗体(HBsAb)共阳性患者乙肝病毒S基因区氨基酸变化特点,了解分子病毒学特征.方法 对26例HBsAg和HBsAb共阳性且DNA阳性的慢性HBV感染者(实验组)和随机选取的39例HBsAg阳性HBsAb阴性且DNA阳性慢性HBV感染者(对照组)的HBV DNA S区基因序列进行PCR扩增和测序,并对S区氨基酸序列进行比对分析.结果 HBsAg和HBsAb共阳性组S基因区氨基酸突变高于对照组,两者差异具有统计学意义(P<0.05);在a决定簇(aa124 ~147)尤其是第1个茎环结构内(aa124 ~ 137)氨基酸突变频率明显高于对照组(5.49%vs 1.09%,P<0.05).结论 HBsAg和HBsAb共阳性患者S基因a决定簇第1个茎环结构氨基酸变异明显增加,推测与HBsAg和HBsAb共阳性现象的发生可能有相关性.  相似文献   

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目的 探讨血清HBsAg与HBV DNA对乙肝患者肝纤维化的相关性分析.方法 选取2010年5月至2014年9月在我院进行治疗的100例肝脏穿刺活组织学检查的患者,根据肝脏炎症程度将患者分为G0-G1、G2、G3-G4三组,根据不同纤维化分期将患者分为S0-S1、S2、S3、S4四组,根据丙氨酸转氨酶(ALT)水平,将患者分为A1 (ALT≤40U/L)组、A2(40<ALT≤80U/L)组,对不同分组患者进行血清HBsAg测定、HBV DNA测定及ALT测定,分析其含量与肝脏炎症程度及纤维化程度的相关性.结果 G0-G1组、G2组、G3-G4组HBsAg定量分别为(3.85±0.87)U/ml、(3.54±0.79) U/ml、(2.79 ±0.58) U/ml,三组间具有统计学差异(P<0.05).G0-G1组、G2组、G3-G4组HBV DNA定量分别为(6.27±1.67) U/ml、(5.68±1.49) U/ml、(5.84±1.59) U/ml,三组间差异无统计学差异(P>0.05).S0-S1组、S2组、S3组、S4组患者HBsAg定量分别为(3.95±0.93) U/ml、(3.62±0.86) U/ml、(3.55±0.62) U/ml、(3.35 ±0.54) U/ml,四组差异有统计学差异(P<0.05).S0-S1组、S2组、S3组、S4组患者HBV DNA定量分别为(6.23±1.72) U/ml、(5.79±1.62U/ml)、(5.50±1.48) U/ml、(5.48±1.35U/ml),四组差异有统计学意义(P<0.05).ALT水平与炎症程度及纤维化程度没有相关性(P>0.05).结论 HBsAg、乙肝病毒随着肝纤维化程度的加重逐渐减低,血清HBsAg结合HBV DNA载量作为检测乙肝病毒感染者肝纤维化指标更为可靠.  相似文献   

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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   

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目的 研究我国发现的乙肝病毒S基因突变株(129Leu和145Arg)表达HBsAg及DNA免疫的特性. 方法 用自乙肝疫苗免疫无保护婴儿血清中克隆的2株变异S基因(其中"a"决定簇突变,分别为nt540A→T,aa129Gln→Leu和nt587G→A,aa145Gly→Arg)片段,置换已知核苷酸序列并可表达及复制的HBV1.2个拷贝全基因野毒株重组质粒p3.8Ⅱ的S基因.将重组质粒转染HepG2细胞,用Abbott试剂和24种单抗检测转染细胞培养上清中HBsAg的结合力.用重组质粒DNA肌肉免疫小鼠. 结果 129Leu变异株转染细胞上清对HBsAg酶联免疫反应检测的吸光度(A)值高于p3.8Ⅱ野毒株,而145Arg变异株的A值低于p3.8Ⅱ;用24种单抗测定的总趋势为129Leu表达的HBsAg 的S/C值高于p3.8Ⅱ,而145Arg的结果则低于p3.8Ⅱ.三者表达的HBeAg水平相似.用DNA免疫经129Leu诱生的抗-HBs水平低于野毒株p3.8Ⅱ,但略高于145Arg. 结论 129Leu变异株表达的HBsAg与HBs多抗及单抗的结合力较野毒株明显增高,但129Leu 变异株DNA免疫诱生的抗-HBs水平却低于野毒株p3.8Ⅱ.免疫原性低下可能有利于129Leu致持续性感染.  相似文献   

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