评估第4代HIV酶联免疫法诊断试剂对静脉吸毒者感染窗口期的检测能力

目的应用BBI公司血清抗体阳转盘评价第4代人类免疫缺陷病毒（HIV）酶联免疫法诊断试剂（以下简称第4代试剂）对窗口期感染的检测能力,并应用其从静脉吸毒人群样本中筛查窗口期感染者,从而分析第四代试剂检测临床样本的特异性和敏感性。方法首先应用第3代HIV酶联免疫法诊断试剂筛查BBI血清阳转盘和收集的吸毒人群样本,阳性样本进一步用免疫印迹法确认。再用第4代试剂分别检测阴性和阳性样本,阴性样本中出现阳性反应者,进行p24抗原和HIV RNA病毒载量检测,证实是否为窗口期样本。对证实为窗口期的感染者随访至抗体阳转。结果用第3代试剂检测BBI阳转血清盘,未发现阳性样本;检测静脉吸毒人群样本2629份,发现HIV抗体阳性样本77份,经免疫印迹法（WB）确认均为阳性,阴性样本2552份。第4代试剂可检出BBI阳转血清盘第14天的窗口期样本;在2552份静脉吸毒人群抗体阴性样本中检出2份窗口期样本,一例随访至血清阳转,一例失访。临床检测特异性为99.2％,假阳性率0.8％（95％可信区间0．4％～1．1％）。结论第4代试剂比第3代试剂能够更早地发现HIV感染者,降低窗口期漏检,减少HIV传播。     

HIV集合核酸检测在男男性行为人群中的应用评价

目的 评估集合核酸检测方法在男男性行为人群(MSM)中的应用,探索适合该人群的HIV早期感染检测策略及应用该方法估算新发感染率的可行性.方法 本研究共采集4 856份2008年4月至2009 年9月我国黑龙江省(4 156份样品)和北京市(700份样品)MSM人群的样品.分别经三代ELISA、四代ELISA和WB检测后,HIV阴性样品进行集合核酸检测.样品集合采用三级集合策略.并计算和比较"三代ELISA检测+WB"、"四代ELISA检测+WB"、"三代ELISA检测+WB+集合核酸检测"和"四代ELISA检测+WB+集合核酸检测"的HIV检测阳性率.4 156份黑龙江省MSM人群样品中符合条件的WB确认阳性样品纳入BED-捕获酶联试验 (BED-CEIA),并应用BED方法和集合核酸检测方法进行新发感染率估算.结果 4 856份样品中共有143份被判定为HIV阳性,其中经三代和四代ELISA检测为阳性的样品均为130份,窗口期感染样品13份.常规ELISA检测加核酸检测能最有效检测出MSM人群窗口期感染者;4种检测策略的HIV检测阳性率分别为:2.68%(95%CI 为2.22%～3.14%)、2.82%(95%CI 为2.35%～3.29%)、2.94%(95%CI 为2.46%～3.42%)和2.94%(95%CI 为2.46%～3.42%),差异无统计学意义(χ2=0.854 3,P=0.836 4).4 156份黑龙江省样品中有88份纳入BED检测,41份样品被判为新近感染.应用BED检测方法和集合核酸检测方法估算的HIV发病率分别为2.36%(95%CI 为1.63%～3.08%)和2.92%(95%CI 为1.01%～4.83%).结论 HIV集合核酸检测技术能有效地筛查出窗口期感染者,可用于我国MSM人群窗口期检测.

Abstract：

Objective To evaluate the application of pooling HIV nucleic acid amplification testing (NAAT) among men who had sex with men (MSM) population, and to investigate suitable HIV screening strategy and the feasibility of calculation of HIV incidence using pooling NAAT among MSM population in China.Methods Four thousand eight hundred and fifty-six samples were collected from MSM population from April 2008 to September 2009 among with 4 156 were in Heilongjiang province and 700 were in Beijing in China. After standard testing with an HIV ELISA and WB confirmation testing, HIV antibody-negative samples were pooled and screened for HIV using NAAT.A three-stage pooling strategy was adopted.The HIV positive rate estimated by the four HIV screening strategies was calculated.In addition, 4 156 HIV positive specimens from Heilongjiang province were screened with the BED capture enzyme immunoassay (BED-CEIA).The HIV-1 incidences were estimated by BED-CEIA assay and pooling NAAT individually.ResultsOne hundred and forty-three of 4 856 subjects were HIV infected.130 were 3rd and 4th generation ELISA positive; 13 were antibody-negative but acutely HIV infected.According to the evaluation of four HIV screening strategies, routine HIV screening test together with pooling NAAT was more effective than other strategies for screening out window period generation ELISA+WB+pooling NAAT' were 2.68%(95% confidence interval CI=2.22%-3.14%), 2.82%(95%CI=2.35%-3.29%), 2.94%(95%CI=2.46%-3.42%) and 2.94%(95%CI=2.46%-3.42%), respectively.The differences were not significant (χ2=0.854 3, P=0.836 4).Of the 88 HIV positive samples from Heilongjiang province, 44 participants were tested as recent HIV infections by BED-CEIA assay. The estimated HIV-1 incidence was 2.36% (95%CI=1.63%-3.08%) and 2.92% (95%CI=1.01%-4.83%) based on BED-CEIA assay and pooling NAAT,respectively.Conclusions Pooling NAAT is a effective screening test in HIV negative population to detect window period infection among MSM population in China.     

运用单样本核酸扩增检测技术对提高深圳地区HIV检出率的效果分析

目的分析运用单样本核酸扩增检测技术(SS-NAT)对提高深圳地区HIV检出能力的效果,探讨SS-NAT对降低输血感染HIV残余风险的作用。方法采用Procleix Tigris单样本核酸检测系统和第三代、第四代两种酶联免疫吸附试验(ELISA)试剂对2015年1月至2017年8月采集的269 228份无偿献血者血液标本进行平行检测。对ELISA检测无反应性而SS-NAT有反应性的标本进行HIV鉴别试验,并对鉴别有反应性的献血者进行追踪检测。所有ELISA或SS-NAT HIV鉴别试验有反应性的样本均送到深圳市疾病预防控制中心(CDC)做免疫印迹法(WB)确证试验。结果 269 228份样本HIV第三代ELISA试剂检测有反应性188份,有反应性率为0.698‰(188/269 228),第四代ELISA试剂检测有反应性340份,有反应性率为1.263‰(340/269 228),两种ELISA试剂共检测有反应性422份,有反应性率为1.567‰(422/269 228),SS-NAT检测有反应性共103份,有反应性率为0.383‰(103/269 228),其中有4份ELISA无反应性而SS-NAT有反应性标本,对应献血者随访追踪血液标本ELISA和SS-NAT均呈有反应性。所有ELISA或SS-NAT HIV鉴别试验有反应性标本经CDC确认有103份标本呈阳性。ELISA检测后HIV窗口期检出率为1∶67 307(4/269 228)。结论 SS-NAT应用于血液筛查可提高HIV检出率,缩短HIV检测窗口期,降低输血感染HIV残余风险,从而有效提高输血安全性。     

ELISA试剂联合检测HIV结果分析

目的选择有效的艾滋病检测模式。方法用国产第四代酶联免疫吸附试验(ELISA)法作为临床标本的艾滋病毒(HIV)筛查;对筛查阳性标本进一步用国产第三代、进口第四代ELISA法复检;复检两种试剂均为阳性或其中任一试剂为阳性,则送重庆市疾病预防控制中心用免疫印迹法(western blot,WB)进行确认。结果国产第四代ELISA法检出144例HIV阳性标本,WB确认阳性132例,阳性符合率为91.67%(132/144);其中131例3个厂家ELISA法均为阳性,且WB确认为阳性,阳性符合率为100%;11例国产第三、四代ELISA法为阳性,进口第四代ELISA法和确认为阴性;1例国产和进口第四代均为阳性,国产第三代ELISA法和确认为阴性;1例国产和进口第四代为阳性,国产第三代为阴性,经确认为阳性。结论用国产第四代ELISA法筛查患者HIV,联合进口第四代ELISA法复检,最后以免疫蛋白印迹法确认的艾滋病检测模式。既节约了成本又缩短HIV检测的窗口期,对预防控制HIV蔓延、减少医院感染和医疗纠纷具有重要意义。     

HIV抗原抗体联合检测试剂在高危人群筛查中的应用

目的：应用第四代人类免疫缺陷病毒（HIV）抗原抗体联合检测试剂,对静脉吸毒及性乱人群、同性恋人群和临床可疑HIV感染患者进行HIV筛查,以了解第四代试剂的检测灵敏度和特异度。方法：分别用第三代和第四代HIV抗原抗体检测试剂,对静脉吸毒及性乱、同性恋、可疑HIV感染人群的样本进行检测,阳性反应样本用免疫印迹法（Westernblot,WB）进行确认;第三代试剂检测为阴性而第四代试剂呈阳性反应的标本,除进行WB确认试验外,再加作P24抗原检测和HIV-1RNA检测。结果：第三代和第四代试剂检测HIV感染的灵敏度均为100%,特异度则分别为97.99%和96.36%。但在早期感染样本中,第四代试剂的阳性反应较第三代试剂强;在检测静脉吸毒及性乱人群样本中,第四代试剂的特异度为99.37%,假阳性率为0.62%（95%可信区间为0.3%～1.2%）;在检测同性恋人群样本中,第三代试剂和第四代试剂的特异度分别为99.03%和98.45%。在可疑HIV感染患者样本中,第三代和第四代试剂筛查呈阳性反应经WB确认的阳性符合率分别为92.86%和89.00%。结论：相对于第三代HIV检测试剂,第四代HIV抗原抗体联合检测试剂诊断HIV感染的灵敏度与之相同,而特异度则稍低。     

无偿献血者中HIV阳性者的病毒载量分析

目的分析无偿献血者艾滋病病毒(HIV)阳性标本的病毒载量水平及无偿献血人群HIV的携带状态,为评估无偿献血人群HIV感染风险提供依据。方法收集2016—2018年国内25家血站HIV筛查反应性(R)的血浆标本683(人)份,根据HIV反应性类型分为ELISA双试剂反应性组(ELISA R-R)、核酸检测(NAT)反应性组(NAT R),ELISA单试剂反应性组(ELISA R-NR),使用电化学发光试剂法做HIV抗原抗体检测,使用核酸定量试剂做HIV RNA定量检测,核酸定量检测低于检测下限(80 IU/mL)的标本以WB法确认。结果本组无偿献血者筛查R标本中,1)HIV确认阳性率为27.1%(185/683),确认阳性样本ELISA R-R标本占89.2%(165/185),ELISA NR-NR+NAT-R占8.1%(15/185),ELISA R-NR占2.7%(5/185),3(种)组病毒载量(IU/mL)分别集中在10~(4.605±0.047)、10~(3.472±0.328)和10~(5.196±0.655)(P0.05);HIV窗口期标本病毒载量(IU/mL)10~5者占20.0%(4/20),其中2例来自ELISA R-NR组,2例来自NAT R组;30.0%(6/20)为10~4者,其中2例来自ELISA R-NR组,2例来自NAT R组;其余50.0%(10/20)为10~1—10~3者,其中1例来自ELISA R-NR组,剩余9例来自NAT R组。2)在HIV确认阳性者中发现3名疑似HIV精英控制者(ECs)。结论我国无偿献血者中HIV ELISA R-R感染者病毒载量较抗原抗体窗口期感染者高;HIV窗口期感染者中多为低载量病毒感染者。疑似HIV ECs的发现揭示我国无偿献血人群HIV感染状态日益复杂多样化,需要加强对血液筛查实验室检测质量的管理,探究更合理的HIV筛查策略。     

核酸检测技术(NAT)在献血者人类免疫缺陷病毒筛查中的应用

目的应用核酸扩增检测(Nucleic Acid Amplification Testing,NAT)技术对人类免疫缺陷病毒(human im-munodeficiency virus,HIV)酶联免疫吸附测定(Enzyme-Linked Immuno Sorbent Assay,ELISA)合格的献血者血液标本进行核酸检测,探讨NAT技术对缩短ELISA检测HIV感染"窗口期"的作用。方法对献血者血液标本进行HIV抗原抗体、乙型肝炎病毒表面抗原、丙型肝炎病毒抗体、梅毒螺旋体抗体2遍ELISA检测,将检测结果合格的血液标本进行核酸检测。结果在177229例ELISA检测合格的献血者标本中发现HBV DNA阳性献血者24例,HIV-1RNA阳性献血者1例,未发现HCV RNA阳性献血者。对HIV-1RNA阳性献血者追踪调查并在献血后的d4、d11、d16、d37采样检测,d4病毒载量由献血时的4.61×102copy/ml上升至5.10×104copy/ml,P24抗原和抗体仍为阴性;d11P24抗原检测阳性,HIV抗体检测仍为阴性。d16HIV抗体检测结果阳性,免疫印迹法(Western blot,WB)确证试验结果为HIV抗体不确定;d37WB确证试验结果为HIV-1抗体阳性。结论 HIV-1RNA阳性献血者,经追踪调查及对不同时间采集的标本采用各种方法学检测,证实该献血者为HIV感染早期ELISA法漏检的"窗口期"献血者。因此,NAT检测技术比ELISA检测能更进一步地缩短HIV检测的"窗口期"。     

多引物小型集合HIV核酸检测技术的建立及在男男性接触者急性感染检测中应用

目的 建立结合多重反转录巢式PCR技术检测HIV RNA的小型集合NAT,用于MSM人群急性感染的筛查诊断.方法 利用2008年10月至2009年3月期间从3名HIV窗口期感染者、30名HIV慢性感染者、97名健康人采集冻存的EDTA抗凝血浆建立小型集合NAT.将10份待测标本混合组成1个集合,离心富集病毒,提取RNA;针对HXB2的nt5783-nt6228和nt1235-nt2012区分别设计2对引物;采用多重RT-PCR、巢式PCR扩增2个目标区的核酸片段,对结果阳性的集合中标本进一步分别检测.确定小型集合NAT的灵敏度,并进行验证.应用建立的方法对1 005份与上述标本同一时期收集的MSM人群的HIV抗体阴性血浆进行检测.结果 (1)成功扩增出目标区的2条特异性片段,灵敏度为162拷贝/ml;(2)对3份HIV窗口期感染者标本用小型集合NAT方法盲法验证的结果和预期一致;(3)用多重RT-PCR和巢式PCR对30份HIV抗体阳性标本检测,阳性率100%(30/30);(4)发现1 005份血浆标本中有1份为HIV RNA阳性,追踪随访发现HIV-1抗体转阳.结论 本研究中建立多引物小型集合RT-PCR、巢式PCR结合的小型集合NAT的敏感性好,可用于MSM人群HIVG感染窗口期筛查检测.     

泉州市318例HIV抗体筛查阳性的确认结果分析

目的通过对318例HIV抗体筛查阳性标本的WB确认结果,分析了解筛查阳性结果与确诊结果之间的关系。方法按《全国艾滋病检测技术规范》进行检测及判断,分析HIV抗体筛查试验为阳性而免疫印迹试验倒B）为不同结果的因素以及相关资料。结果318份筛查阳性标本经WB确认后,227份确认为HIV-1抗体阳性（71．4％）,48份确认为HIV—1抗体不确定（15．1％）,43份确认为HIV-1抗体阴性（13．5％）。阳性标本中ELISA的S／CO值均〉6,ELISA和快速试剂复检结果为双阳性的标本,确认试验阳性符合率97．8％（227／232）。在不确定标本中,p24出现的几率最高,为85．4％,其次是gp160,58.3％。结论高S/CO值预示HIV抗体阳性的可能性较大且ELISA结合快速试验有助于提高复检的准确率,不确定标本出现较多．确认方法有待改进．     

献血者HIV RNA窗口期标本的追踪和随访

目的对处于HIV RNA窗口期的献血者做追踪、随访和验证。方法分别使用第3、4代酶联免疫试验(ELISA)方法(试剂)、免疫印迹试验(WB),以及核酸检测技术(NAT)定性和定量等方法,对在血液筛查中检出的1例献血者HIV窗口期不同时间(根据献血者的配合度间隔4-8 d)的血液标本做追踪和随访检测。采用ELISA方法以双试剂检测抗-HIV;同时采用全自动NAT单检分析系统,对该例血液标本做了HBV、HCV、HIV 3项NAT联检和鉴别试验。结果该例献血者标本首次检测:ELISA抗-HIV非反应性,NAT定性试验反应性;随后NAT定量试验和抗-HIV确认试验(WB)也同为阴性。采用双试剂ELISA和WB确认方法对献血者追踪、随访检测4次,至3周后确认为血清学抗-HIV转阳,获得到了1个完整的血清学转化结果。结论首次追踪、随访检测得以确认1例重庆地区病毒载量较高的HIV RNA窗口期献血者;NAT检测有利于阻截该HIV RNA窗口期献血者的血液流向临床。     

Specificity and sensitivity of first and second generation anti-HCV ELISA in a low prevalence population

Specificity and sensitivity of the second generation enzyme immunosorbent assay for hepatitis C antibodies were calculated from data on 208,554 blood donors screened with either the first or the second generation tests (ELISA I, ELISA II) or both (4,639 donors). The second generation ELISA was no more specific than the first generation test in this low-prevalence blood donor population (specificity 99.7% vs 99.6%). Most of the donors (93.5%) who were found to be reactive using ELISA II were negative or indeterminate according to a supplemental test, the second generation recombinant immunoblot assay (RIBA II). The second generation ELISA was found to be more sensitive than the first. It identified all 16 donors who were positive according to RIBA II during screening with ELISA I. The latter found only 13 out of 30 donors (43%) who were positive according to RIBA II during screening with ELISA II. If the number of RIBA II positive donors found during the first year of screening with ELISA I (74, 0.024%), and the number of RIBA II positive but ELISA I negative donors found during screening with ELISA II, are taken into consideration it can be estimated that the added sensitivity due to using ELISA II is about 40%.     

内源性物质对第2、3代抗-HIV ELISA初筛试验的影响

酶联免疫吸附试验(ELISA)是人类免疫缺陷病毒抗体(抗-HIV)筛选试验中最常用的方法,目前国外已有第四代产品上市,由于受抗原研制水平等因素的限制,国内使用的抗-HIV ELISA试剂仍以第2代试剂(间接法)及第3代试剂(双抗原夹心法)为主.应用这两代试剂进行HIV抗体初筛时,常常会遇到假阳性现象,尤以第2代试剂更为常见,笔者就其影响因素进行了探讨.     

Anti-hepatitis C virus serology in patients affected with congenital coagulation defects: a comparative study using three second generation ELISA tests

We determined the prevalence of anti-hepatitis C virus (HCV) antibodies in 34 patients affected with congenital coagulation disorders attending the Haemophilia Centre of Padua, Italy. Serological tests were carried out by three second generation enzyme linked immunosorbent assays (ELISA), two based on recombinant proteins (Ortho and Abbott) and one based on synthetic peptides (Behring) as antigenic substrate. The repeatedly reactive specimens were further assayed by the supplemental 4-antigen recombinant immunoblot assay (RIBA) (Chiron and Ortho). Moreover, we performed the dot-blot Matrix test (Abbott) on the samples showing discrepant results by the three ELISA tests. Twenty-six patients (76.5%) were anti-HCV positive using all three ELISA tests; 25 were confirmed by the supplemental RIBA test, the other one was indeterminate. Two samples were in a gray-zone only using the anti-HCV ELISA Abbott. These were positive by the RIBA; in contrast, such samples showed no reactivity with the Matrix test. In accordance with the current literature, these data show an equivalence between the 2nd generation screening tests (ELISA), at least when applied to a high risk population as in the present study. Further, these screening tests demonstrated a reliable specificity, since most of the ELISA-reactive specimens were confirmed by the supplemental RIBA test. In contrast, combined use of the anti-HCV tests could be useful when high sensitivity is requested, as in the case of blood donor pretransfusion screening.     

ELISA for human proinsulin

A micro enzyme-linked-immunosorbent-assay (ELISA) for monitoring circulating human proinsulin (hPI) was developed. A micro test plate was coated with guinea pig anti-insulin antibody. As labelling system peroxidase-labelled F(ab1)2-fragments of a guinea pig anti-human-C-peptide was used. The detection limit in buffer (95% level) was 0.6 pmol/l corresponding to 0.06 fmol/incubation well and to 1.2 pmol/l in serum, since samples were diluted 50%. Standard operating range was from 0-160 pmol/l. Interassay variation was 9% estimated from two human control materials (assayed within the range 6-9 pmol/l and 9-14 pmol/l, respectively). Insulin in samples did not interfere in concentrations below 400 pmol/l. Human C-peptide, porcine, and bovine proinsulins did not cross-react even at 10 000 pmol/l. In 38 healthy fasting subjects a reference range less than 1.2-13 pmol/l with a median of 4.1 pmol/l was found. Serum from total pancreatectomised patients showed values below the detection limit. The value from a patient with an insulinoma was 263 pmol/l. When stored at -20 degrees C human proinsulin appeared stable in serum or plasma for at least 9 mth. This ELISA, although among the most sensitive immunoassays for human proinsulin, is still not sensitive enough to measure the concentrations expected in samples from IDDM patients in the fasting state. In spite of this the method is useful in characterising beta-cell function in stimulated situations, as well as in the diagnosis of insulinoma.     

ELISA assay for colon cancer

The high mortality rate for patients with colon cancer results largely from the inability to diagnose the condition in its early stages. The assay described in this report may be useful in early detection of colon cancer. In the study we use the cotton-top tamarin, Saguinus oedipus, as an animal model for studying human colon cancer. This New World monkey develops a high incidence of colitis and colon cancer. Antibodies that recognize adenocarcinoma cells and antigens from these cells can be detected in the sera of tamarins with colon cancer. The antibodies are not found in sera of healthy animals. In one procedure, tamarin adenocarcinoma cells are used to coat the wells of a microtiter plate. In an alternate procedure, a glycoprotein adenocarcinoma antigen is used. The antigen is extracted from a cultured tamarin colon cancer line by detergent solubilization followed by affinity chromatography. Test sera are examined by adding biotinylated immunoglobulin serum fractions to the coated wells. The wells are washed and an avidin-enzyme conjugate is added. Positive sera are identified by the addition of the substrate. The presence of the autoantibodies in the sera may be taken as evidence that the animal has colon cancer.     

ELISA法测定血清瘦素

目的 建立ETJSA测定血清瘦索的方法。方法 制备瘦素单克隆抗体，以双抗体夹心法测定血清瘦素。结果 方法的平均回收率为89．7—92．1％。取浓度为1．21μg／L、6．32μg/L瘦素标本其批内变异分别为4．4％和2．6％；批间变异分别为5．7％和4．9％。方法的线性为：1．25—20μg／L。与放射免疫法比较有良好的相关性（r^2=0．9988）。参考值范围为：5．26—5．92μg／L。结论 该法简便、快速、特异、敏感，适于临床常规应用。     

ELISA联合检测方法的建立及应用

目的在微孔板平台上建立多指标联合检测的方法,为急诊、门诊及基层等多种医疗机构提供1种新的血清学检测手段。方法本研究根据酶联免疫吸附法(ELISA法)原理,以卵泡刺激素(FSH)、泌乳素(PRL)、黄体生成素(LH)、生长激素(GH)为检测靶标,在自行设计的聚苯乙烯板孔上完成反应体系的优化,包括FSH、PRL、LH、GH包被抗体浓度及酶标抗体浓度,建立1种并行分析样品中多种指标的方法。结果成功确定4种垂体激素联合检测的条件,包括4种激素抗体包被浓度、酶标抗体浓度等,并成功应用于临床样本的检测。结论本研究首次建立了1种简单、特异性高、成本低、并行分析4种垂体激素的联合检测方法,提高了常规ELISA法的检测效率。     

Measurement of transcobalamin by ELISA

BACKGROUND: Transcobalamin is essential for the cellular internalization of cobalamin. Methods to quantify the unsaturated protein are available, but few attempts have been made to develop methods to quantify the sum of unsaturated and cobalamin saturated transcobalamin. METHODS: gamma-Globulins from two polyclonal rabbit antibodies against recombinant human transcobalamin were used as capture and detection antibodies, and recombinant human transcobalamin was used as calibrator in an ELISA design. RESULTS: The ELISA is specific for transcobalamin and has a detection limit of <1.6 pmol/L. The imprecision (CV) is 4-6% for mean concentrations of 13-70 pmol/L. The central 95% interval for serum from healthy blood donors (n = 77) was approximately 600-1500 pmol/L and showed limited variation with age and sex. No correlation was observed between the marker of acute phase reaction, C-reactive protein, and transcobalamin in plasma. CONCLUSIONS: The ELISA measures total transcobalamin in serum and thus can be used for measurement of transcobalamin in patients treated with cobalamin.