Comparison of a Chemiluminescent Immunoassay with Two Microparticle Enzyme Immunoassays for Detection of Hepatitis B Virus Surface Antigen

A comparative evaluation of the following commercial immunoassays for the detection of hepatitis B virus surface antigen (HBsAg) was performed: the Abbott AxSYM, Abbott IMx, and DPC IMMULITE assays. The specificity was 100% for all assays. Twelve samples were identified and were confirmed to be positive for HBsAg by all three methods. One additional sample was identified as reactive and was confirmed to be positive by the Abbott AxSYM assay only. Prior to confirmation testing the DPC IMMULITE assay produced significantly fewer false-positive results than the Abbott AxSYM assay (P < 0.05).     

化学发光法和酶联免疫法作为筛选试验测定丙肝抗体的评价

目的比较化学发光法(CLIA)和酶联免疫法(EIA)测抗-HCV对诊断HCV感染的检出率,分析CLIA测定抗-HCV作为HCV感染初筛试验的重要临床意义。方法分别用CLIA、EIA方法检测所有临床标本中的抗-HCV,选取抗-HCV初筛阳性样本进行HCV RNA确认试验。结果 6461例样本中,EIA和CLIA测抗-HCV阳性率分别为2.86%和3.17%;确认试验中,CLIA法抗-HCV阳性与HCV RNA的符合率为97.1%,显著高于EIA组(91.9%)。EIA法测抗-HCV,S:CO>5.0以上,与HCV RNA检测符合率可达100%;弱阳性样本,与HCV RNA符合率为69.7%;CLIA法测抗-HCV,S:CO>2.0以上,与HCV RNA检测符合率可达100%;弱阳性样本,与HCV RNA符合率为92.9%。有31例样本CLIA法抗-HCV和HCV RNA阳性,而EIA法抗-HCV阴性;有4例样本EIA法检测为阳性,而CLIA法和PCR确认试验均为阴性。结论CLIA法测抗-HCV作为HCV感染初筛实验,与传统EIA相比,特异性和阳性预测值更高,有效降低了假阳性率,有利于临床医生对HCV感染患者的早期诊断和治疗。     

Comparison between Elecsys HBsAg II and Architect HBsAg QT Assays for Quantification of Hepatitis B Surface Antigen among Patients Coinfected with HIV and Hepatitis B Virus

Hepatitis B surface antigen (HBsAg) quantification has been steadily gaining interest as a clinical marker of therapeutic efficacy, for which two commercial assays are currently available: Architect HBsAg QT (Architect) and Elecsys HBsAg II (Elecsys). HBsAg quantification was evaluated using both assays in 126 human immunodeficiency virus (HIV) and hepatitis B virus (HBV)-coinfected patients initiating treatment with tenofovir dipivoxil fumarate. Linear regression and correlation were used to establish the relationship between the two methods. Bland-Altman analysis was performed to determine mean between-assay difference and limits of agreement (LOA) (±2 standard deviations [SD]) both overall and stratified on HBV (hepatitis B envelope antigen [HBeAg] status, replication, genotype, HBV mutants) or HIV (CD4⁺ cell count) cofactors. There was a significant correlation between Elecsys and Architect assays (correlation coefficient, r = 0.959; P < 0.001). HBsAg quantification using the Elecsys assay was on average 0.200 log₁₀ IU/ml (LOA, −0.500, 0.800) higher than that using Architect, which was consistent across levels of CD4⁺ cell count, presence of precore and YMDD mutations, and HBeAg status. A slightly larger mean between-assay difference was observed with genotypes A and G (0.196 and 0.201, respectively) versus HBV genotypes D and E (0.036 and 0.030, respectively). Mutations on the S region at position s120/s145 were the only determinant in which the mean between-assay difference in HBsAg quantification was lower than the null value (−0.078). In conclusion, the Elecsys assay, with automatic on-board dilution, is capable of quantifying serum HBsAg levels in HIV-HBV-coinfected patients, with very high correlation with the Architect assay.     

化学发光免疫分析血清C肽方法建立

双抗体夹心一步法建立人C肽(C-peptide) 化学发光免疫分析(CLIA)方法.方法可测范围0.15～15ng/mL,灵敏度0.02ng/mL,批内、批间变异系数(CV)分别为4.2%～6.5%和6.8%～9.3%,与胰岛素无交叉反应,与胰岛素原的交叉反应率为7.3%.本方法与国外同类试剂盒同时检测40份C-肽释放试验血清,相关系数为0.9709.本方法各项指标均满足临床检测要求,达到国外同类产品水平.     

HBsAg定量与HBV-DNA联合检测在慢性乙型肝炎中的临床意义

目的 探讨慢性乙型肝炎病毒(HBV)感染患者表面抗原定量检测与HBV-DNA相关性,并探讨其检测临床意义.方法 检测2010年12月至2012年12月200例未接受抗病毒治疗及免疫调节剂治疗的慢性HBV感染患者治疗前、治疗中HBsAg与HBV-DNA水平,并随访20例治疗后HBV-DNA转阴患者HBsAg与HBV-DNA水平变化,探究HBsAg定量检测临床意义.结果 慢性乙型肝炎患者未接受抗病毒治疗及免疫调节剂治疗前HBeAg(+)患者HBsAg与HBV-DNA水平显著正相关(r =0.683,P＜0.05),HBeAg(-)患者两者正相关性,但相关性较低(r=0.273,P＜0.05).治疗过程中HBsAg与HBV-DNA水平呈正相关(r=0.41,P＜0.01),65.5％ (131/200)的变化规律为HBsAg随HBV-DNA含量的下降而下降.20例HBV-DNA治疗后转阴(HBV-DNA＜500拷贝/mL)患者,其中6例治疗期间HBsAg定量持续下降,HBsAg定量均＜ 250IU/mL,停药后24周复检HBV-DNA仍为阴性.14例治疗后乙肝病毒定量转阴患者(HBV-DNA＜ 500拷贝/mL),治疗期间HBsAg定量不降或上升,停药后24周复检病毒定量有4例(4/14)出现反弹(HBV-DNA＞ 500拷贝/mL).结论 血清HBsAg含量与HBV-DNA具有相关性,临床可将HBsAg含量与HBV-DNA联合检测,用于慢性HBV感染患者的病情程度预判,监测临床治疗疗效.     

Quantitation of Immunoglobulin to Hepatitis E Virus by Enzyme Immunoassay

We developed a quantitative enzyme immunoassay (EIA) for antibody to hepatitis E virus (HEV) by using truncated HEV capsid protein expressed in the baculovirus system to improve seroepidemiology, to contribute to hepatitis E diagnosis, and to enable vaccine evaluations. Five antigen lots were characterized; we used a reference antiserum to standardize antigen potency. We defined Walter Reed antibody units (WR U) with a reference antiserum by using the four-parameter logistic model, established other reference pools as assay standards, and determined the conversion factor: 1 WR U/ml = 0.125 World Health Organization unit (WHO U) per ml. The EIA performed consistently; median intra- and intertest coefficients of variation were 9 and 12%, respectively. The accurate minimum detection limit with serum diluted 1:1,000 was 5.6 WR U/ml; the test could detect reliably a fourfold antibody change. In six people followed from health to onset of hepatitis E, the geometric mean antibody level rose from 7.1 WR U/ml to 1,924.6 WR U/ml. We used the presence of 56- and 180-kDa bands by Western blotting as a confirmatory test and to define true-negative and -positive serum specimens. A receiver-operating characteristics plot identified 30 WR U/ml as an optimum cut-point (sensitivity, 86%; specificity, 89%). The EIA detected antibody more sensitively than a commercially available test. The EIA was transferred to another laboratory, where four operators matched reference laboratory results for a panel of unknowns. Quantitation of antibody to HEV and confirmation of its specificity by Western blotting make HEV serology more meaningful.     

Development of a Simple and Highly Sensitive Enzyme Immunoassay for Hepatitis C Virus Core Antigen

A highly sensitive enzyme immunoassay (EIA) for the hepatitis C virus (HCV) core antigen (HCVcAg) was developed, and its performance was compared with that of the AMPLICOR HCV test (Roche Molecular Systems). The developed one-step pretreatment method, 30-min incubation of the specimen with a solution containing three different types of detergents (Triton X-100, 3-[(3-cholamidopropyl)-dimethylammonio]-1-propanesulfonate [CHAPS], and sodium dodecyl sulfate), does not require any special device. Because the interfering anti-core antibody in the sample was sufficiently inactivated by the pretreatment, HCVcAg in the sample could be detected. The immunoreactivity on gel filtration was shifted from void fractions to those corresponding to the molecular mass range from 20 to 25 kDa, which is equal to the estimated molecular mass of HCVcAg, after the pretreatment. By the recovery test with HCVcAg-positive serum, the recovery rate was 93.5 to 106. 5%. There was no interference with the EIA by anticoagulants or blood components in the serum. When the cutoff value was tentatively set at 0.5 mU/ml based on the distribution of healthy subjects' sera, the sera of all healthy subjects (n = 125) and patients with hepatitis B (n = 50) were negative. HCVcAg was detected in sera from 57 of 73 individuals (78.1%) with anti-HCV antibody. Similarly, HCV RNA was detected in sera from 59 individuals (80.8%) with the AMPLICOR HCV as the qualitative test (AMPLICOR HCV test) and in sera from 54 individuals (74.0%) by the AMPLICOR HCV Monitor as the quantitative test (AMPLICOR Monitor test). Concentrations of HCVcAg and HCV RNA (measured by the AMPLICOR Monitor test) correlated significantly (r = 0.8, P < 0.001). On seroconversion panels, HCVcAg was detected during the early stage of infection, when anti-HCV antibodies had not been produced. This assay for HCVcAg is simpler than assays for HCV RNA based on gene technology and shows specificity and sensitivity equivalent to those of the AMPLICOR HCV test.     

癌抗原15-3酶促化学发光免疫分析方法的建立

目的 建立癌抗原15-3(CA15-3)酶促化学发光免疫分析方法.方法 利用双抗体夹心法建立CA15-3化学发光检测体系,分别对该体系的最低检测限、线性、分析特异性、准确度和精密度进行评估,并与进口全自动化学发光检测结果进行对比.结果 本方法灵敏度为0.26 U/mL,线性范围为0～ 300 U/mL,与CEA和CA125无交叉反应,添加回收率在97.0％ ～105.6％之间,分析内与分析间CV均小于10％,与进口全自动化学发光试剂同时检测160份样本的CA15-3浓度,检测结果的线性相关系数为0.987.结论 成功建立了CA15-3酶促化学发光免疫分析方法.该方法灵敏度高、重复性好,在临床应用中可替代进口化学发光检测试剂.     

化学发光免疫分析法检测乙肝病毒感染性标志物的临床应用

目的 探讨化学发光免疫分析法检测乙肝病毒感染性标志物的临床应用效果.方法 抽取我院2013年1月至2014年1月接收的疑似乙型肝炎病人800例,采用化学发光免疫分析法(CLIA)和酶联免疫吸附试验法(ELISA)分别检测患者的乙肝病毒血清标志物.结果 HBsAg、HBeAg、HBeAb的检出率CLIA高于ELISA(P＜0.01),两种方法HBsAb、HBcAb的检出率无明显差异(P＞0.05);低水平HBsAg检测ELISA敏感性低于CLIA;ELISA检出的最低浓度为0.128IU/mL,CLIA法检出的最低浓度为0.0311U/mL.结论 采用CLIA检测乙肝病毒感染性标志物相比ELISA更准确,可有效应用于乙肝临床诊断和病情动态监测.     

C反应蛋白酶联免疫分析和化学发光免疫分析的建立及其初步应用

采用高纯度的C反应蛋白(CRP)免疫兔,获取高效价的CRP抗体.提取抗血清中IgG,包被酶标板.用生物素标记CRP抗原,辣根过氧化物酶标记亲和素,建立CRP的ELISA和化学发光免疫分析法(CLIA).用ELISA测定正常人80名,心梗患者43例和重症监护室(ICU)病人39例的血清CRP水平,发现心梗患者(27.21±38.67μg/mL)明显高于正常人(0.57±2.99μg/mL)(P《0.05);ICU病人(117.48±97.05μg/mL)明显高于正常人及心梗患者(P《0.001和P《0.01).用CLIA检测正常人68名,结果为0.77±3.29μg/mL.随机收集病人血清样品73份,分别用免疫比浊法、ELISA和CLIA检测,经统计三种方法高度相关.结果提示:ELISA和CLIA是一种简便、灵敏和特异的CRP测定方法,可用于人血清中CRP的测定.     

前列腺特异抗原化学发光免疫分析方法的建立及初步应用

建立的前列腺特异抗原(PSA)化学发光免疫分析(CLIA)使用2株抗PSAMcAb,一株McAb包被微孔板,另一株McAb与HRP连接。底物是鲁米诺/H2O2/对碘苯酚系统的双抗体夹心一步法,测定范围0.5～64ng/mL,最低检出值为0.13ng/mL,平均回收率为100.6%,批内和批间CV分别小于8.3%和11.5%,正常参考值小于3.5ng/mL。1000份血清临床考核,与参比试剂盒临床符合率一致,具有同等的临床诊断价值。     

Novel Double-Antigen Sandwich Immunoassay for Human Hepatitis B Core Antibody

A novel diagnostic immunoassay testing procedure for hepatitis B virus core antibody (anti-HBc) using homogeneous purified full-length hepatitis B virus core antigen (HBcAg) capsids obtained from Escherichia coli was compared with Abbott Architect anti-HBc chemiluminescent microparticle immunoassay (CMIA; indirect method) against a library of specimens. A monoclonal anti-HBc neutralization confirmatory assay was then used to determine the degree of discordance between specimens. The new assay was found to be superior in both sensitivity and specificity.Antibodies (anti-HBc) to hepatitis B virus (HBV) core antigen (HBcAg) are present in current and past HBV infections. Anti-HBc antibodies represent a long-term serological marker of HBV infection, initially appearing during the acute phase of the infection and generally persisting thereafter (16). Thus, as anti-HBc is a universal marker of HBV infection, routine blood donor screening for anti-HBc has been implemented in some countries with low endemicity. It is a cost-effective method of screening. Such screening procedures have resulted in a decrease in the risk of posttransfusion HBV infections (12). In some individuals, the only serological marker of HBV infection is the presence of anti-HBc antibodies (10, 24), and thus detection of “anti-HBcAg alone” could reflect unrecognized “occult” HBV infection and physicians should consider investigating such patients with HBV molecular tests (21). Additionally, isolated anti-HBc can be used as a marker to assess the risk of HBV reactivation in patients undergoing therapy that could result in immunosuppression or patients who are HIV positive (17) or hepatitis C virus (HCV) positive (25).With these uses in mind, having a more efficient and reliable assay for anti-HBc is desirable. Most current commercially available anti-HBc assays have poor sensitivity or specificity (2, 19) and can be attributed to the inferior performance of the competitive immunoassay, especially for detecting low-titer anti-HBc-reactive samples. False-positive reactivity can partially be attributed to unspecific activation of premature B lymphocytes causing the production of IgM, IgA, or IgM-related molecules without previous exposure to HBV (18, 19). The specificity of competitive assays for anti-HBc can be significantly improved by addition of mild reducing agents, but such modified procedures often lead to the loss of sensitivity, particularly for IgM anti-HBc (23). In this study, a novel immunoassay for anti-HBc based on the double-antigen sandwich enzyme-linked immunosorbent assay (ELISA) method is compared with a commercial anti-HBc assay, the Architect chemiluminescent microparticle immunoassay (CMIA).     

乳铁蛋白酶免疫分析法的建立及乳品含量检测的初步应用

目的：建立乳铁蛋白（LF）酶免疫分析法,检测LF在血清及乳汁中的水平。方法：用人源的LF多次免疫兔,获得高效价的抗体。纯化后包被成固相酶标板,以识别并结合待测标本中的LF。用生物素标记抗原（Bio-Ag）,同辣根酶标记亲和素（HRP-A）可特异结合。向固相酶标板中同时加入Bio-Ag和不同浓度的标准品,37℃反应1.5h。洗涤后以HRP-A为探针,经酶底物显色后可获得良好的ELISA竞争抑制曲线。结果：该法测定范围：（0.36～9.00）μg/ml,最低检出量0.25μg/ml,批内和批间误差分别为〈6.3%和7.4%。用该法测正常献血员（40名）血清LF水平为（0.438±0.183）μg/ml;人初乳（5名）水平为（7.82±0.51）mg/ml。血清和初乳中的LF经65℃30min处理后活性不变,经100℃3min处理明显降解。结论：该法稳定、简便、特异适于检测人血清和乳汁中的LF水平。     

Highly Sensitive Detection of Hepatitis B Virus Surface Antigen by Use of a Semiautomated Immune Complex Transfer Chemiluminescence Enzyme Immunoassay

The performance of hepatitis B surface antigen (HBsAg) screening assays is continuously improved to reduce the risk of transfusion-associated hepatitis B. In this study, a semiautomated immune complex transfer chemiluminescence enzyme immunoassay (ICT-CLEIA) for the detection of HBsAg, which is as sensitive as hepatitis B virus (HBV) DNA PCR, was developed; the ICT-CLEIA assay performance was compared with the performance of the Architect HBsAg QT assay and HBV DNA PCR. The specificities in the initial assay and after retesting were 99.50% (1,988/1,998 samples) and 99.95% (1,997/1,998 samples), respectively. The analytical detection limit was determined to be 0.2 mIU/ml using the 2nd International WHO HBsAg standard, and the cutoff value (0.5 mIU/ml) of the ICT-CLEIA assay was 8.0 standard deviations (SD) above the mean of the HBsAg-negative specimens. The ICT-CLEIA assay could detect HBsAg even in the presence of anti-HBs antibodies and demonstrated a 23.6-day-shorter window period using commercially available HBsAg seroconversion panels than the Architect HBsAg QT assay. Furthermore, the monitoring of the viral kinetics by the ICT-CLEIA assay and the HBV DNA PCR produced very similarly shaped curves during both the HBsAg seroconversion and reverse seroconversion periods. Therefore, the ICT-CLEIA assay may be useful not only for an earlier detection of HBV reactivation but also for the monitoring of hepatitis B patients.     

HBsAg、HBsAb共存乙型肝炎患者S基因"a"决定簇变异检测分析

目的:研究HBsAg、HBsAb共存慢性乙型肝炎患者HBV S基因“a”决定簇变异情况及对HBsAg抗原性的影响。方法:对7例HBsAg、HBsAb同时阳性慢性乙型肝炎患者的8份血清,采用竞争PCR微流芯片法定量检测HBV DNA;用套式PCR法扩增HBV S基因,对PCR产物进行直接测序,比较S基因的核苷酸和推导出的氨基酸序列的差异,采用ELISA/MEIA法检测HBVM;以15例HBsAg、HBeAg/HBeAb、HBcAb阳性乙肝疫苗免疫失败儿童、9例终末期乙肝患者肝移植术后接受HBIG、拉米夫定治疗患者作为对照。结果:7例患者HBsAb含量均低于80mIU/ml,其中2例HBVDNA定量阳性者未出现“a”决定簇变异,4例HBVDNA定量阴性者中2例氨基酸发生变异(126,131),1例HBV DNA定量由阳性转为阴性者由无变异转为氨基酸126位点变异;9例肝移植术后痊愈患者HBsAb含量均高于150mIU/ml,HBV DNA定量均为阴性,未发现“a”决定簇变异;15例免疫失败儿童14例HBV DNA定性阳性,2例出现“a”决定簇145位点、1例126位点、1例134位点氨基酸变异。结论:部分HBsAg、HBsAb共存慢性乙肝患者、乙肝疫苗免疫失败儿童体内存在S基因“a”决定簇变异;“a”决定簇变异可改变HBsAg抗原性、逃避低含量抗HBs的中和作用;“a”决定簇变异对HBV的复制可能有一定影响;肝移值治愈乙肝患者未发现“a”决定簇变异。     

合成肽作抗原酶免疫技术检测非甲－戊型肝炎病人血清中抗HGV

本文应用人工合成肽作为抗原建立了检测庚型肝炎病毒（ＨＧＶ）抗体的酶免疫技术（ＥＩＡ），最适抗原包被浓度为４μｇ／ｍｌ。在特异性验证的基础上，检测了３４例非甲－戊５型肝炎病人血清和３２例丙型肝炎感染病人血清。结果表明，在ＨＧＶ感染高危人群中，诸如输血后肝炎－丙型肝炎中有较高的ＨＧＶ的感染率。本方法的建立为临床上难于作出诊断的庚型肝炎提供了敏感、特异、易于应用的新技术。     

新型气动左心辅助循环装置动物存活实验

目的　应用自行研制的气动左心辅助泵 (罗叶泵 )进行动物存活实验 ,探讨其对血流动力学、血液有形成分和肝肾功能的影响及其临床应用的可行性 ;方法　健康山羊 12只 ,体重 2 9.7～ 39.4kg ,平均 34.1kg ,从左心房至降主动脉间转流 ,进行左心辅助循环 (LVAD) ,辅助频率为 6 0次 /分 ,流量为 2～ 3L/min ;结果　本组山羊LVAD时间为 13～174小时 ,平均 89小时 ,LVAD过程中 ,动物血压、中心静脉压稳定 ,尿液正常 ,肝肾病理检查未见坏死及出血灶 ;肌酸激酶同功酶、乳酸脱氢酶在辅助 4 8小时较术前明显升高 ,分别为 396 8.70± 15 6 1.2 5U/L ,2 0 18 0 0± 6 4 9 12U/L ,但 72小时后逐渐恢复正常 ,游离血红蛋白LVAD 4 8小时为 4 81 12± 116 .16mg/L ,在LVAD 72小时降至正常范围 (2 91.13±12 1.13mg/L) ;结论　罗叶泵能有效地维持血流动力学稳定 ,性能稳定、可靠 ,说明该血泵已具备条件进行短期临床试用     

化学发光免疫分析定量检测乙肝病毒标志物方法学研究

采用碱性磷酸酶标记,金刚烷衍生物发光,自动化学发光分析仪测量等,进行乙肝病毒五种标志物化学发光免疫分析(CLIA)方法学研究.结果表明这五种标志物CLIA方法的精密度、灵敏度、回收率和临床符合率等技术参数均达到方法学和临床诊断的要求.CLIA方法比ELISA和RIA更简便、快速而实用,为临床诊断和科研工作提供了一种有用的检测手段.     

Baculovirus Expression of Chimeric Hepatitis B Virus Core Particles with Hepatitis E Virus Epitopes and Their Use in a Hepatitis E Immunoassay

Two hepatitis B core proteins bearing the immunodominant region of the hepatitis E virus (HEV) capsid protein, one at the C terminus of hepatitis B virus core antigen (HBcAg) and the other within the HBcAg immunodominant loop, were constructed. Both chimeric proteins exhibited HEV reactivity, but only the first construct retained HBcAg reactivity. The second construct was used to develop an anti-HEV test which is equivalent to a commercial test for the detection of anti-HEV immunoglobulin G (IgG) but is more sensitive for the detection of anti-HEV IgM.