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1.
Algorithm of serologic screening for HBsAg-mutants in hepatitis B virus (HBV) carriers with high level of HBsAg was developed which is based on the detection of defects of interactions of serum HBsAg with monoclonal anti-HBs realizing as a decrease of ELISA sensitivity in 10 times or more during serial 10-fold dilutions. During 1st stage commercial test-systems based on monoclonal antibodies was used to select serum samples with discrepancy of test results. During 2nd stage HBsAg contained in selected sera was analyzed by the panel of monoclonal and polyclonal anti-HBs conjugates using decrease in ELISA sensitivity as a criterion. Serum samples from 2510 chronic carriers of HBV with high level of HBsAg were studied. 19 samples with discrepant results were found. Subsequent characterization of HBsAg with panel of 11 monoclonal and 1 polyclonal conjugates allowed to distinguish groups of sera with specific serologic "portraits". Atypical features of HBsAg were confirmed by genotyping 9 of 19 samples. Analysis of primary nucleotide sequence revealed serologically meaningful mutations in S-gene of HBV in all 9 isolates: 3 of them contained substitution mutation G145R, 5--S143L, and one--T143M. Distribution of mutations in HBsAg corresponded with specific serologic "portraits". Prevalence of HBsAg mutations in HBV carriers with high level of HBsAg was assessed for the first time: prevalence of G145R, S143L/T143M mutations, and all serologically atypical variants was 0.12%, 0.24%, and 0.76% respectively. Developed algorithm was proposed for epidemiologic monitoring of HBsAg-mutants of HBVand control of diagnostic test-systems.  相似文献   

2.
HRP-HBVDNA探针在临检应用中的研究   总被引:2,自引:0,他引:2  
本文介绍了一种简便的检测血清HBVDNA的方法。参照Renz等人的标记方法,构建了直接酶标HRP HBVDNA探针。此探针经与固定在硝酸纤维素滤膜上的血清靶DNA杂交后,可通过化学发光自显影检测技术观察结果。敏感度可检测0-1pg靶DNA,相当于同位素探针的灵敏度。对63份HBsAgHBeAg和Anti HBcELISA阳性血清以及24份HBsAgAnti HBc阳性,HbeAg阴性血清用HRP HBVDNA探针进行检测,结果探针HBVDNA阳性率分别为100%(63)和58%(14);对50份HBsAg,ELISA阴性和ALT正常的血清,探针HBVDNA全部阴性。实验结果表明本方法具有很大的推广应用价值。  相似文献   

3.
The gene encoding MAP30 protein was cloned from bitter melon and recombinant MAP30 was expressed and purified. The human hepatoma G2.2.15 cells were exposed to different concentrations of MAP30. MTT assay was used to evaluate the cytotoxicity of the drugs and real-time PCR and Southern hybridization were applied to quantify extracellular HBV DNA and replicative intermediates intracellular and cccDNA in nucleus. HBsAg and HBeAg were assessed by enzyme-linked immunosorbent assay (ELISA). The results showed that exposure of HepG2.2.15 cells to MAP30 resulted in inhibition of HBV DNA replication and HBsAg secretion. After exposed to three different concentrations of MAP30 for 2, 4, 6, and 8 days respectively, the inhibition rates of extracellular HBV DNA, HBsAg, and HBeAg of each concentration decreased significantly (P < 0.05). After 9 days of treatment, the inhibition rates of extracellular HBV DNA of the different concentrations differed greatly (P < 0.001). The MAP30 could inhibit the production of HBV (P < 0.01) dose-dependently. The expression of HBsAg was significantly decreased by MAP30 dose-dependently (P < 0.001) and time-dependently (P < 0.001). Lower dose of MAP30 (8.0 μg/ml) could inhibit the expression of HBsAg and HBeAg.  相似文献   

4.
Hepatitis B virus (HBV) DNA in the serum of 31 patients with histologically confirmed primary hepatocellular carcinoma (PHC) from Malaysia and Indonesia was quantitated by densitometric scanning of autoradiograms obtained by Southern blot DNA hybridization, after electrophoresis using a 32P DNA cloned into plasmid pBR325 as a probe. This quantitation after electrophoresis is more informative than the usual spot hybridization technique. Five of the 31 sera were positive for HBV DNA. Levels ranged between 1.36 pq and 143.18 pq per ml of serum, and the levels of HBsAg, anti-HBs, anti-HBc, HBeAg and anti-HBe in the serum were serologically determined. All five sera positive for HBV DNA were also positive for HBsAg. Three of the five positive for HBV DNA were positive for HBeAg and negative for anti-HBe. Two of the sera positive for HBV DNA were negative for HBeAg but positive for anti-HBe. All sera negative for HBV DNA were also negative for HBeAg. Many sera which were negative for HBV DNA and HBeAg were positive for HBsAg. Of the 31 sera from PHC patients, 23 had at least one HBV marker positive (74.2%).  相似文献   

5.
Antibody to hepatitis B surface antigen (HBsAb) is the important serological marker of the hepatitis B virus (HBV) infection. Conventionally, the hepatitis B surface antigen (HBsAg) obtained from the plasma of HBV carriers is used as the diagnostic antigen for detection of HBsAb. This blood-origin antigen has some disadvantages involved in high cost, over-elaborate preparation, risk of infection, et al. In an attempt to explore the suitable recombinant HBsAg for the diagnostic purpose, the HBV S gene was expressed in Pichia pastoris and the product was applied for detection of HBsAb. Hepatitis B virus S gene was inserted into the yeast vector and the expressed product was analyzed by sodium dodecyl sulphate polyacrolamide gel electrophoresis (SDS-PAGE), immunoblot, electronic microscope and enzyme linked immunosorbent assay (ELISA). The preparations of synthesized S protein were applied to detect HBsAb by sandwich ELISA. The S gene encoding the 226 amino acid of HBsAg carrying a hexa-histidine tag at C terminus was successfully expressed in Pichia pastoris. The His-Tagged S protein in this strain was expressed at a level of about 14.5 % of total cell protein. Immunoblot showed the recombinant HBsAg recognized by monoclonal HBsAb and there was no cross reaction between all proteins from the host and normal sera. HBsAb detection indicated that the sensitivity reached 10 mIu (micro international unit)/ml and the specificity was 100 % with HBsAb standard of National Center for Clinical Laboratories. A total of 293 random sera were assayed using recombinant S protein and a commercial HBsAb ELISA kit (produced by blood-origin HBsAg), 35 HBsAb positive sera and 258 HBsAb negative sera were examined. The same results were obtained with two different reagents and there was no significant difference in the value of S/CO between the two reagents. The recombinant HBV S protein with good immunoreactivity and specificity was successfully expressed in Pichia pastoris. The reagent for HBsAb detection prepared by Pichia pastoris-derived S protein showed high sensitivity and specificity for detection of HBsAb standard. And a good correlation was obtained between the reagent produced by recombinant S protein and commercial kit produced by blood-origin HBsAg in random samples.  相似文献   

6.
Current hepatitis B virus (HBV) vaccines consist of preparations of recombinant HBV major surface antigen (sAg) and are protective in about 90-95% of vaccinated subjects. In improved vaccines, the frequency of nonresponders to the classical vaccine could be reduced by including additional epitopes from the preS-domains of the middle and large surface antigens. In this report, the development and characterization of a CHO cell line for HBsAg, expressing major, middle, and large antigens are described. Despite the previously reported retention of secreted proteins by the preS1 domain, cell lines could be amplified that secreted large amounts of the complete set of antigens. A producer line was established that expressed 1mg HBsAg per 100ml suspension culture per week during exponential growth. The productivity per cell increased further by at least threefold when the culture reached the stationary phase at high cell densities. In the production cell line, several hundred copies of the HBV vector were integrated at two adjacent sites into chromosome 2. The cell line was adapted to growth in a defined protein-free medium minimizing the risk of adventitious agents introduced by animal derived supplements. The cell line stably produced antigen over several months. In the candidate vaccine, both preS2 and preS1 domains were present at ratios similar to HBsAg from human sera. In summary, a production cell line for an improved HBV vaccine is presented with properties such as high productivity, long term stability of expression, and growth in protein-free media.  相似文献   

7.
HBV感染中抗-(抗-HBs)独特型抗体的研究   总被引:1,自引:0,他引:1  
1.75%聚乙二醇(MW6000)沉淀血清免疫复合物后,采用ELISA法检测上清中抗独特型抗体〔抗-(抗-HBs)〕。56例急性HBV感染患者血清IgM抗-(抗-HBs),第一周检出率最高(60.00%),1个月后大部分阴性,IgG抗-(抗-HBs)维持时间略长。IgM抗-(抗-HBs)较HBsAg/IgM和IgM抗-HBc消失早,将有利于急性HBV感染的诊断。27例CAH和29例CPH,IgM和IgG抗-(抗-HBs)阳性率约为38~52%,两型间无显著差异(p>0.5)。3例无症状HBsAg携带者和12例HBsAg血清疫苗接受者血清,抗-(抗-HBs)阴性。115例HBV感染者中,IgM抗-(抗-HBs)阳性者HBsAg阳性率(93.62)显著高于IgM抗-(抗-HBs)阴性者(52.31%),p<0.005;反之,HBsAg阳性血清IgM抗-(抗-HBs)阳性率(55.5S%)显著高于HBsAg阴性血清(9.68%),p<0.005;IgM抗-(抗-HBs)阳性和阴性血清的HBVDNA阳性率有显著差异(p<0.025),IgG反应到类似的结果。以上资料表明,抗-(抗-HBs)提示了一些HBV感染患者体内可能存在一种缺陷的反馈机制,导致抗-HBs产生不足而容许更活跃的HBV复制。本文证明了HBV感染患者血清中存在的抗-(抗-HBs)可能是共同决定簇“a”特异性的,还表明抗-HBs人抗-Id反应可能被纯化人血清HBsAg抑制,提示人抗-(抗-HBs)与抗-HBs结合的位点可能在HBsAg与抗-HBs结合位点内或在其附近,这和一些动物抗-(抗-HBs)的研究结果是一致的。  相似文献   

8.
Hepatitis B virus (HBV) infection continues to be a global public health concern. Efficient diagnosis of HBV surface antigen (HBsAg) is useful for identification of infection, treatment and prevention of transfusion‐transmitted viral infections. Seronegative window reduction afforded by a highly sensitive measurement methodology is necessary as a small quantity of virus with infection risk exists for the period characterized by undetectable HBsAg following HBV infection. In this study, a bioluminescent enzyme immunoassay (BLEIA) for HBsAg was developed employing firefly luciferase as a labeling enzyme and a two‐step sandwich immunoassay method. The cut‐off value (10 mIU/mL) was 50‐fold more sensitive relative to conventional chemiluminescent enzyme immunoassay based on luminol luminescence involving peroxidase as the labeling enzyme and the identical antibodies. Preliminary clinical data for this BLEIA revealed that the HBV seroconversion panel derived sequentially from HBV‐infected human blood was detected 11 days following window closure from the first bleed, whereas detection occurred 14–25 days following window closure with the three conventional commercial kits. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

9.
近年来,用8型腺相关病毒携带1.3拷贝HBV(Hepatitis B virus)基因组建立的HBV持续感染小鼠模型受到越来越多的关注。本研究比较了除AAV8之外的其他4种血清型重组腺相关病毒(Recombinant adeno-associated virus,rAAV)建立乙肝小鼠模型效果。首先,将携带1.3拷贝ayw亚型HBV基因组的1型、2型、5型、8型、9型腺相关病毒分别以1×10~(11) vg/只(Viral genome,vg)的剂量尾静脉注射C57BL/6J小鼠;利用ELISA方法监测小鼠血清中HBeAg和HBsAg表达水平;用定量PCR方法检测小鼠血清和肝脏中HBV DNA拷贝数;用免疫组化方法检测小鼠肝脏中HBc Ag的表达;用HE染色检测小鼠肝脏病理变化。结果显示,在持续8周中,5组小鼠血清中都检测到HBeAg和HBsAg的表达,血清和肝脏中均检测到HBV DNA的存在。HBeAg、HBsAg、HBV DNA表达水平高低依次为AAV8AAV9AAV1AAV5AAV2。5组小鼠用免疫组化方法都检测到肝脏中HBcAg表达,HE染色病理检测均观察到不同程度的肝损伤。本研究扩大了能用于建立乙肝小鼠持续感染模型可选择的AAV载体种类,发现虽然AAV1、2、5、9的建模效果不如AAV8,但它们都可以介导建立持续感染的乙肝小鼠模型,建模效果依次为AAV8AAV9AAV1AAV5AAV2。其中AAV9介导的建模效果与AAV8载体最为接近,可以替代AAV8载体用于有效地建立HBV持续感染的小鼠模型。  相似文献   

10.
Two variants of sandwich-type ELISA (Enzyme Linked Immunosorbent Assay) kits for HBsAg detection (Sevatest ELISA HBsAg Macro I and Sevatest ELISA HBsAg Micro I) in human sera and plasmas were developed. As the solid phase, the ELISA Macro kit and ELISA Micro kit make use of polystyrene microtubes, and polystyrene microtitration plates, respectively, of Czechoslovak production (Koh-i-noor, Dalecín). Capture anti HBs antibody for adsorption to solid phase and rabbit anti HBs antibody for labelling with horse-radish peroxidase were prepared for both tests. The sensitivity of both ELISA kits for HBsAg, equal to approx. 2 ng/ml, was determined by titrating six selected HBsAg-positive sera and the WHO Agk 76 panel of HBsAg-positive sera and the results were compared with those obtained by ELISA, RIA (Radioimmunoassay) and RPHA (Reverse passive hemagglutination) kits of different producers and by counter-immunoelectrophoresis (CIEP). The sensitivity of the new ELISA kits was comparable to that of other producers' ELISA kits, higher than that of RPHA kits and only a little lower than that of RIA kits. A set of sera of patients hospitalised with different diagnoses was tested for HBsAg. The detection rate by ELISA Macro kit 2.8 and 1.5 times higher than by CIEP and RPHA (Raphadex B), respectively, and 1.1 time lower than by RIA (Austria II).  相似文献   

11.
Intervertebral disc (IVD) degeneration is a common cause of back pain, and attempts to develop therapies are frustrated by lack of model systems that mimic the human condition. Human IVD organ culture models can address this gap, yet current models are limited since vertebral endplates are removed to maintain cell viability, physiological loading is not applied, and mechanical behaviors are not measured. This study aimed to (i) establish a method for isolating human IVDs from autopsy with intact vertebral endplates, and (ii) develop and validate an organ culture loading system for human or bovine IVDs. Human IVDs with intact endplates were isolated from cadavers within 48 h of death and cultured for up to 21 days. IVDs remained viable with ~80% cell viability in nucleus and annulus regions. A dynamic loading system was designed and built with the capacity to culture 9 bovine or 6 human IVDs simultaneously while applying simulated physiologic loads (maximum force: 4 kN) and measuring IVD mechanical behaviors. The loading system accurately applied dynamic loading regimes (RMS error <2.5 N and total harmonic distortion <2.45%), and precisely evaluated mechanical behavior of rubber and bovine IVDs. Bovine IVDs maintained their mechanical behavior and retained >85% viable cells throughout the 3 week culture period. This organ culture loading system can closely mimic physiological conditions and be used to investigate response of living human and bovine IVDs to mechanical and chemical challenges and to screen therapeutic repair techniques.  相似文献   

12.
13.
本研究以与血清中HBV DNA含量高度相关的两种HBV抗原(前S1抗原与核心抗原)为靶标,建立了联合检测这两种HBV核酸相关抗原(NRAg)的双抗体夹心法ELISA试剂.对系列稀释血清的检测表明,该试剂的平均分析灵敏度为103.2基因组拷贝/mL(95%可信限102.2-4.2基因组拷贝/mL),显著高于前S1抗原或核心抗原的单独检测.对994份HBsAg阴性血清的检测结果表明NRAg ELISA的特异性为99.7%(95%可信限:99.1%~99.9%).对271份临床慢性肝炎血清进行检测,结果NRAg ELISA与HBV DNA结果的总符合率达96.3%(95%可信限:93.3%~98.2%),NRAg ELISA的读值/临界值比(S/CO)与HBV基因组拷贝数呈正相关.利用NRAg试剂,发现了1例HBsAg"a"抗原表位突变的变异株.这些结果显示HBV NRAg ELISA与HBV DNA具有高度相关性,并能够检测出HBsAg抗原变异株,有望成为HBsAg变异株筛选的有力工具,并为广大基层医疗单位提供一种便捷的替代HBV DNA定性检测的手段.  相似文献   

14.

Background

The aim of this study was to investigate the correlation between the expression of hepatitis B surface antigen (HBsAg) in human ovary and placenta and the vertical transmission of hepatitis B virus (HBV).

Methodology/Principal Fidnings

Ovarian and placental tissue specimens of pregnant women infected with HBV were collected during cesarean section and immunostained for HBsAg. The sera of the corresponding newborns were tested for HBV markers and HBV DNA. HBsAg was detected in 15 out of 33 (45%) placental tissues and was further detected in capillary endothelial cells in 4 specimens (26%), of which 3 (75%) corresponding infants were infected with HBV in utero. Out of the 33 ovarian tissues, 7 (21%) were positive for HBsAg, of which 2 (28%) showed HBsAg in ovarian follicles and the 2 corresponding infants (100%) had intrauterine HBV infection.

Conclusions/Significance

HBsAg expression in cells of the ovarian follicle or placental capillary endothelium signal a higher risk for intrauterine HBV infection.  相似文献   

15.
Chemical modifications were performed on hydroxyl groups at C-11,23,24,25 positions and C-13(17) double bond of alisol A for structure–activity relationship study. Forty-one derivatives of alisol A were synthesized and assayed for their in vitro anti-hepatitis B virus (HBV) activities and cytotoxicities. Of them, 14 compounds were active against HBV surface antigen (HBsAg) and HBV e antigen (HBeAg) secretion in HepG 2.2.15 cells, and the most promising compound 25 exhibited high activities against secretion of HBsAg (IC50 = 0.028 mM), HBeAg (IC50 = 0.027 mM) and remarkable selective indices (SIHBsAg >90, SIHBeAg >93).  相似文献   

16.
新婚夫妇HBV感染的研究   总被引:2,自引:0,他引:2  
为了研究性因素在乙型肝炎传播中的意义,对1697对婚前登记的男女用RIA法检测血清HBV指征(HBsAg、抗-HBs、抗-HBc)。选出57对一方HBsAg和抗-HBc阳性,另一方为HBV易感者做为实验观察组,61对双方均为HBV易感者做为对照观察组。婚后27个月第二次抽血,双份血清用同一批RIA试剂检测HBV指征。结果,实验组HBV易感方HBsAg阳转率为14.04%,HBV感染率为52.63%;对照组HBsAg阳转率为1.64%,HBV感染率为16.03%。两组比较,相对危险性为:HBsAg RR=8.6,HBV RR=3.1,差异非常显著,P <0.01。  相似文献   

17.
The purpose of the research was to determine the influence of the hepatitis B virus on the progression of the chronic liver disease. In the present paper, 127 patients who were followed up for five years and who had histologically verified chronic liver disease, are described. Fifty two of them were carriers of HBsAg, 75 patients were HBsAg negative, but had other markers typical for a previous infection of HBV in the sera. All the patients were nonalcoholics and no drug addicts. In the sera of these 127 patients markers of HBV were prospectively followed up: HBsAg, HBeAg, anti-HBs, anti-HBc, anti-HBe, HBVDNA, antiHCV for C virus and anti-D for D virus. It was proved by these investigations that HBV provokes very severe chronic hepatitis: CAH (chronic active hepatitis) and CH (cirrhosis hepatis). It was also proved that HBV replicated in 44.20% patients, namely, HBVDNA was positive in the sera of those patients. In 26.08% of such patients the mutant form of HBV was present. In spite of progressive liver disease and without any antiviral therapy all the patients with chronic HBV cirrhosis hepatis were, after five year-follow-up, in Child-Pugh A grade. It was found that the patients who were HBsAg negative, but had one or more markers of HBV positive in the sera, had also a severe chronic hepatitis. That group of patients remains our object of further research. The five-years follow-up of all these patients demonstrates that it is necessary to find out an efficient medicament against HBV chronic hepatitis. Obligatory vaccination of the risk population against virus B remains the only prevention against this severe disease.  相似文献   

18.

Background & Aims

Dried blood spots (DBS) on filter paper have been successfully used to diagnose and monitor several infectious diseases. The aim was to investigate the performance of DBS in hepatitis B virus (HBV) diagnosis using commercial tests in comparison to standard methods.

Methods

Paired DBS and plasma samples were collected from 200 patients: 100 patients with HBsAg negative status and 100 patients with HBsAg positive status. In the latter patient, HBeAg reactivity was tested. Ten samples of anti-HBs were collected from people vaccinated against HBV. We also studied 50 patients with positive HBV DNA viral load in plasma and 10 HBV DNA negative patients. HBV genotypes and gene polymerase mutations were determined in 10 randomly selected HBV-infected patients. The DBS sample consisted of 50 µL of whole blood, i.e. a 12-mm paper card.

Results

The sensitivity thresholds of HBsAg and anti-HBs antibody were 0.30±0.08 IU/mL and 18.11±6.05 IU/mL, respectively, for DBS with 98% sensitivity and 100% specificity. Sensitivity was 98% and specificity 100% for the detection of HBV DNA on a blotter, considering an HBV DNA threshold of 914.1±157.8 IU/ml. Ten patients had an HBeAg positive status in plasma, all were detected positive using DBS. HBV genotyping and mutation detection were successfully performed on DBS, with full concordance between the 10 paired DBS and plasma samples.

Conclusion

This study shows DBS is a reliable alternative to plasma specimens for quantifying and detecting HBsAg, anti-HBs, HBeAg and genotyping. DBS may increase the opportunities for HBV testing and treatment follow-up in hard-to-reach individuals.  相似文献   

19.
The aim of the current study was to detect HBV by Real time - PCR in chronic hepatitis B patients. Fifty-eight sera of chronic hepatitis B patients were subjected during the period March 2009 to April 2010 in Ilam cities in West of Iran. Sera assayed by real-time PCR and ELISA methods. Twenty serum samples from healthy volunteers and non-hepatitis B patients and negative for hepatitis B seromarkers served as negative controls for the study. Among fifty-eight sera, ELISA showed fifty-five (94.8%) of the samples were positive for HBsAg and three (5.2%) negative results obtained while real-time PCR specified fifty-eight (100%) positive results in chronic hepatitis B patients. HBsAg status did not necessarily reflect HBV DNA level in the serum, as 5.2% of chronic Hepatitis B patients were positive for HBV DNA but negative for HBsAg. HBV DNA was not found to be positive amongst any of the negative controls. Real time - PCR is a sensitive and reproducible assay for HBV DNA quantization.  相似文献   

20.
迄今所发现的唯一的戊型肝炎病毒(HEV)中和表位定位于开放读码框架2(ORF2)编码蛋白的第578和第607氨基酸(aa)之间的区域。将对应此区域的基因片段通过一段柔性的甘氨酸铰链与乙型肝炎病毒(HBV)表面抗原(HBsAg)基因的3′端相连,构建成HBV/HEV融合基因。该融合基因在毕赤酵母细胞内的表达产物物为分子量约29kDa的融合蛋白,具有组装成嵌合病毒样颗粒(VLP)的能力。此嵌合VLP具有与HBsAgVLP相似的特性且保留了天然HBV/HEV双重抗原性。对此嵌合VLP特性的初步研究提示其可能具有HBV/HEV双价重组疫苗的潜在应用前景。  相似文献   

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