肺炎支原体抗原酶联免疫检测方法的建立

目的采用ELISA技术,建立肺炎支原体（Mycoplosma pneumonia）抗原检测方法。方法制备肺炎支原体的多克隆抗体,建立酶联免疫吸附法,检测标本中的肺炎支原体,对其敏感性和特异性进行检测。结果本方法可以检测毒株的1／2^12的稀释样品,对甲型流感病毒（H3N2亚型、H1N1亚型）、乙型流感病毒、副流感病毒（Ⅰ型、Ⅲ型）、呼吸道腺病毒（Ⅲ型、Ⅶ型）、肺炎衣原体无特异性反应。结论本肺炎支原体抗原检测方法可用于疑似肺炎支原体感染样品的临床诊断和鉴别诊断。     

甲型流感病毒NS1抗原捕获ELISA的建立

目的 建立基于单克隆抗体的甲型流感病毒非结构蛋白1(NS1)抗原检测的酶联免疫吸附(ELISA)法.方法 用甲型流感病毒NS1特异性单克隆抗体,通过抗体的优化组合,建立双抗体夹心抗原捕获ELISA,检测不同来源的流感病毒及副流感病毒.结果 对多种抗体组合进行反复筛选,最终确定了特异性检测到甲型流感病毒的NS1蛋白,而与乙型流感病毒和副流感病毒不发生交叉反应的最佳抗体组合.该方法 检测重组H5N1-NS1[A/HongKong/486/97(H5N1)-NS1和A/Vietnam/1194/04(H5N1)-NS1]蛋白的灵敏度最低检测值分别为15.6 ng/ml和240 pg/ml.结论 成功建立了甲型流感病毒NS1抗原捕获ELISA,为建立甲型流感病毒感染早期诊断新方法 奠定基础.     

甲型流感病毒NS1抗原捕获ELISA的建立

目的 建立基于单克隆抗体的甲型流感病毒非结构蛋白1(NS1)抗原检测的酶联免疫吸附(ELISA)法.方法 用甲型流感病毒NS1特异性单克隆抗体,通过抗体的优化组合,建立双抗体夹心抗原捕获ELISA,检测不同来源的流感病毒及副流感病毒.结果 对多种抗体组合进行反复筛选,最终确定了特异性检测到甲型流感病毒的NS1蛋白,而与乙型流感病毒和副流感病毒不发生交叉反应的最佳抗体组合.该方法 检测重组H5N1-NS1[A/HongKong/486/97(H5N1)-NS1和A/Vietnam/1194/04(H5N1)-NS1]蛋白的灵敏度最低检测值分别为15.6 ng/ml和240 pg/ml.结论 成功建立了甲型流感病毒NS1抗原捕获ELISA,为建立甲型流感病毒感染早期诊断新方法 奠定基础.     

甲型流感病毒NS1抗原捕获ELISA的建立

目的 建立基于单克隆抗体的甲型流感病毒非结构蛋白1(NS1)抗原检测的酶联免疫吸附(ELISA)法.方法 用甲型流感病毒NS1特异性单克隆抗体,通过抗体的优化组合,建立双抗体夹心抗原捕获ELISA,检测不同来源的流感病毒及副流感病毒.结果 对多种抗体组合进行反复筛选,最终确定了特异性检测到甲型流感病毒的NS1蛋白,而与乙型流感病毒和副流感病毒不发生交叉反应的最佳抗体组合.该方法 检测重组H5N1-NS1[A/HongKong/486/97(H5N1)-NS1和A/Vietnam/1194/04(H5N1)-NS1]蛋白的灵敏度最低检测值分别为15.6 ng/ml和240 pg/ml.结论 成功建立了甲型流感病毒NS1抗原捕获ELISA,为建立甲型流感病毒感染早期诊断新方法 奠定基础.     

用间接ELISA检测抗H9亚型AIV独特型单克隆抗体的研究

目的为制备抗H9亚型A型流感病毒(AIV)独特型杂交瘤细胞系,运用异种动物间共有独特型理论建立的间接ELISA进行检测.方法本试验采用兔抗H9亚型低致病力AIV IgG作为检测抗原,通过预试验确定了包被抗原的工作浓度为800μg/mL,以间接ELISA方法检测融合细胞培养上清液,筛选到产生抗AIV鸡和兔种间共有独特型抗体的杂交瘤细胞.结果间接ELISA试验中P/N值达12,效价达到2-4,证明杂交瘤细胞株分泌目的单克隆抗体的能力强.结论该检测方法排除了分泌抗鸡同种型表位以及超变区其他表位抗体的杂交瘤细胞,从而成为筛选分泌抗H9亚型AIV独特型单克隆抗体杂交瘤细胞株的可靠方法.     

2009甲型H1N1流感流行期间北京急性呼吸道感染儿童常见呼吸道病毒的研究

目的了解2009至2010年甲型H1N1流感大流行期间北京地区急性呼吸道感染患儿中,除流感病毒外的其他几种常见呼吸道病毒感染的流行情况。方法设计并建立检测包括呼吸道合胞病毒（RSV）A/B亚型,副流感病毒（PIV）1、2、3型,腺病毒（ADV）和人博卡病毒（HBoV）在内的多重实时荧光PCR方法,并应用该方法对2009年6月至2010年2月甲型H1N1流感大流行期间,对首都儿科研究所附属儿童医院就诊的急性呼吸道感染患儿中甲型H1N1流感病毒检测阴性的咽拭子标本进行上述呼吸道病毒的核酸检测。结果新建立的多重RT-PCR方法最低可检测的目标基因含量为10～300拷贝数,未见与其他非目标病毒的交叉反应。本研究共检测标本849份,病毒检测总阳性率为39.0%（331份）,5岁以下占87.6%（290/331份）。各病毒的检测阳性率分别为RSV-A亚型1.4%（12份）,RSV-B亚型8.4%（71份）,PIV-1型8.2%（70份）,PIV-2型0.5%（4份）,PIV-3型3.9%（33份）,ADV13.9%（118份）,HBoV2.7%（23份）。RSV检出以B亚型为主（85.5%）,流行高峰在2009年11月至2010年2月。PIV检出以PIV-1型及PIV-3型为主,PIV-1型的流行高峰在2009年7月至2009年10月,PIV-2型及PIV-3型的流行高峰在2009年6～9月。ADV病毒在研究期间均有较高检出率（平均为13.9%）,HBoV的流行高峰在2009年9～12月。结论除流感病毒外,ADV、RSV-B及PIV可能也是2009甲型H1N1流感流行期间引起儿童急性呼吸道感染的重要病原。比较以往的资料可见各病原在2009甲型H1N1流感流行期间的流行季节性及检出率基本未受到新型流感病毒的影响。     

流感病毒型别及亚型的多重RT-PCR方法快速检测

目的为适应流感疫情监测中快速诊断的需要,建立敏感特异的流感病毒多重逆转录PCR(MRTPCR)检测方法。方法对甲1型(H1N1)、甲3型(H3N2)、乙型流感病毒的血凝素(HA)基因保守区域分别设计引物进行MRTPCR。另设计了两对引物对H1N1和H3N2亚型流感病毒的神经氨酸酶(NA)N1、N2作亚型判断。结果MRTPCR可特异性检测出各型流感病毒的目的片段,相互间无交叉反应。二次PCR反应后对H1N1、H3N2流感病毒的检测灵敏度可达0.10TCID50/50μl以下,对乙型流感病毒的检测灵敏度可达0.01TCID50/50μl以下。应用此方法也可特异性地检测出H1N1和H3N2流感病毒的NA基因。结论用MRTPCR从临床患者含漱液标本中检出相关流感病毒的灵敏度要高于用狗肾传代细胞(MDCK)或鸡胚分离的灵敏度,达到了快速、敏感、正确检测流感病毒及其亚型的目的。     

禽流感病毒血凝素H5特异性单克隆抗体的制备及ELISA捕获法的建立

目的 制备和鉴定禽流感病毒(H5N1)血凝素(H5)特异性单克隆抗体(mAb),建立H5抗原的双抗体夹心ELISA捕获法.方法 以H5血凝素和携带H5全长基因的质粒免疫Balb/c小鼠制备mAb,利用血凝抑制(HI)实验筛选和鉴定,通过竞争抑制试验分析抗体识别表位,并采用抗体配对试验筛选捕获抗体和检测抗体,建立测定H5抗原的双抗体夹心ELISA捕获法.结果 获得16株特异性针对H5的单克隆抗体,与A型流感病毒H1、H3、H7、H9和B型流感病毒的血凝素无HI交叉反应,对H5血凝素的血凝抑制效价为1:100～1:51 200;通过配对实验,建立以单克隆抗体H5M9为捕获抗体,辣根过氧化物酶标记单克隆抗体H5M11为检测抗体的双抗体夹心ELISA;检测多株H5N1病毒和H5血凝素的最低检出值为1/32血凝单位,检测A型流感病毒H1N1、H3N2、B型流感病毒以及H7、H9血凝素均为阴性.结论 建立了一种灵敏度高、特异性强的测定H5抗原的ELISA捕获法,可应用于禽流感病毒H5N1感染的实验室早期诊断.     

用间接ELISA检测抗H9亚型AIV独特型单克隆抗体的研究

目的为制备抗H9亚型A型流感病毒(AIV)独特型杂交瘤细胞系，运用异种动物间共有独特型理论建立的间接ELISA进行检测。方法本试验采用兔抗H9亚型低致病力AIV IgG作为检测抗原，通过预试验确定了包被抗原的工作浓度为800μg/mL，以间接ELISA方法检测融合细胞培养上清液，筛选到产生抗AIV鸡和兔种间共有独特型抗体的杂交瘤细胞。结果间接ELISA试验中P／N值达12，效价达到2^-4，证明杂交瘤细胞株分泌目的单克隆抗体的能力强。结论该检测方法排除了分泌抗鸡同种型表位以及超变区其他表位抗体的杂交瘤细胞，从而成为筛选分泌抗H9亚型AIV独特型单克隆抗体杂交瘤细胞株的可靠方法。     

H5N1流感病毒M1蛋白免疫制备的单克隆抗体的研究

目的 制备抗人流感病毒H5N1株M1蛋白的单克隆抗体,为流感的快速诊断和研究提供新的工具.方法 应用在大肠埃希菌中表达的人H5N1亚型禽流感病毒(A/Anhui/1/2005)株M1蛋白,以纯化的表达产物免疫BALB/c小鼠,取脾细胞与sp2/0细胞系作细胞融合后,间接ELISA法筛选阳性的杂交瘤细胞,并应用间接免疫荧光法对抗体的特异性进行鉴定.结果 获得3株能稳定分泌抗禽流感病毒M1抗原的McAb杂交瘤细胞株,交叉反应试验及间接免疫荧光检测表明,三株McAb具有型特异性.结论 用H5N1禽流感病毒M1蛋白免疫制备的单克隆抗体,具有一定的交叉反应性,可用于多种亚型甲型流感病毒的检测.     

Detection of Nonhemagglutinating Influenza A(H3) Viruses by Enzyme-Linked Immunosorbent Assay in Quantitative Influenza Virus Culture

To assess the efficacy of novel antiviral drugs against influenza virus in clinical trials, it is necessary to quantify infectious virus titers in respiratory tract samples from patients. Typically, this is achieved by inoculating virus-susceptible cells with serial dilutions of clinical specimens and detecting the production of progeny virus by hemagglutination, since influenza viruses generally have the capacity to bind and agglutinate erythrocytes of various species through their hemagglutinin (HA). This readout method is no longer adequate, since an increasing number of currently circulating influenza A virus H3 subtype (A[H3]) viruses display a reduced capacity to agglutinate erythrocytes. Here, we report the magnitude of this problem by analyzing the frequency of HA-deficient A(H3) viruses detected in The Netherlands from 1999 to 2012. Furthermore, we report the development and validation of an alternative method for monitoring the production of progeny influenza virus in quantitative virus cultures, which is independent of the capacity to agglutinate erythrocytes. This method is based on the detection of viral nucleoprotein (NP) in virus culture plates by enzyme-linked immunosorbent assay (ELISA), and it produced results similar to those of the hemagglutination assay using strains with good HA activity, including A/Brisbane/059/07 (H1N1), A/Victoria/210/09 (H3N2), other seasonal A(H1N1), A(H1N1)pdm09, and the majority of A(H3) virus strains isolated in 2009. In contrast, many A(H3) viruses that have circulated since 2010 failed to display HA activity, and infectious virus titers were determined only by detecting NP. The virus culture ELISA described here will enable efficacy testing of new antiviral compounds in clinical trials during seasons in which nonhemagglutinating influenza A viruses circulate.     

A multiplex real-time RT-PCR for detection and identification of influenza virus types A and B and subtypes H5 and N1

A multiplex real-time RT-PCR method for the simultaneous detection of influenza virus types A and B and identification of subtypes H5 and N1 in a single tube is described. The method was developed with four sets of primers and probes which were specific to influenza virus (sub)types A, B, H5, and N1, and evaluated by using a total of 40 influenza virus reference strains, including 17 avian influenza A (12 H5N1, 1 H1N1, 1 H3N2, 1 H4N6, 1 H7N3, and 1 H9N2), 18 human influenza A (11 H3N2, 6 H1N1 and 1 H5N1) and 5 influenza B viruses. The method exhibited a high specificity and sensitivity of approximately 10(1)-10(2)copies/microl for each (sub)type and a high reproducibility with intra- and inter-assay CV from 0.13 to 4.24%. In an analysis of 189 clinical samples from patients during the year 2004 and 2005, the method identified 81 positive samples (42.9%) and identified simultaneously 14 type B samples and 11 subtype N1 samples, in comparison only 46 positive samples (24.3%) identified by the conventional culturing method. The method would be a useful molecular diagnostic tool for large-scale screening of clinical samples for influenza virus.     

Monitoring epidemic viral respiratory infections using one-step real-time triplex RT-PCR targeting influenza A and B viruses and respiratory syncytial virus

Rapid and specific diagnosis of influenza A/B and respiratory syncytial virus (RSV) viruses is needed for optimal management of patients with acute respiratory infections. In this study, a one‐step triplex real‐time RT‐PCR assay was developed for rapid diagnosis of influenza A/B and RSV infections to optimize diagnosis efficiency of acute respiratory infections. Cell‐culture supernatants and clinical samples were used to evaluate specificity and sensitivity of the assay. The assay was used routinely during two winter epidemics for testing respiratory specimens from 2,417 patients. The limit of detection in cell‐culture supernatant was 1–10 plaque forming units/input (influenza A/B) and 2 × 10^?2 50% tissue culture infectious dose/input (RSV). In clinical samples, the assay was as sensitive as commercial molecular assays for the detection of each influenza A/B and RSV (Flu‐A/B and RSV‐A/B r‐gene?) individually, and far more sensitive than antigen detection. During the winter 2008–2009, the assay identified 145 RSV, 42 influenza A, and one mixed RSV‐influenza A infections among 298 patients. The next winter, the assay was used in two independent hospital laboratory settings. 776 patients were tested in one hospital and 1,343 in the other, resulting in 184 and 501 RSV, 133 and 150 influenza A, and 1 and 11 mixed RSV‐influenza A infections, respectively, being detected. This new user‐friendly assay allows rapid (within hours), effective molecular diagnosis of single or mixed infections involving influenza A (including seasonal A H1N1 and H3N2, and A(H1N1) 2009), influenza B, and RSV(A/B). The assay is very valuable for managing patients during winter epidemics when influenza and respiratory syncytial viruses co‐circulate. J. Med. Virol. 83:695–701, 2011. © 2011 Wiley‐Liss, Inc.     

流感病毒快速检测方法在儿童流感样病例病原诊断中的应用

目的对一种流感病毒快速检测方法在儿童流感样病例病原诊断中的应用效果进行评估。方法 2010年12月至2011年4月采集流感样病例患儿咽拭子标本350例,使用甲型及乙型流感病毒抗原检测试剂盒（QuickNaviTM-Flu,胶乳免疫层析法）进行抗原检测,并与病毒分离法进行比较。对于抗原检测和病毒分离法结果不相符的标本采用RT-PCR验证。结果 QuickNaviTM-Flu抗原快速检测流感病毒的结果与病毒分离法的一致性好,其检测甲型流感病毒的敏感度为89.9%,特异度为94.4%。经RT-PCR验证,14例抗原检测与病毒分离法结果不相符样本中13例结果为阳性（与抗原检测一致）,使得该抗原检测方法的敏感度和特异度升至91.0%和99.6%。抗原检测乙型流感病毒经RT-PCR验证前后的结果一致,敏感度和特异度分别为87.5%和100%。该方法检测出的阳性标本中包括了甲3型、乙型（Victoria和Yamagata系）流感病毒和新发的2009甲型H1N1,并与常见的呼吸道病毒之间无交叉反应。结论 QuickNaviTM-Flu作为流感病毒抗原检测的试剂盒,可一次同时检测出甲型和乙型流感病毒,耗时短,操作简便,具有良好的敏感度和特异度,适用于流感样病例病原的快速诊断。     

Interferon production by human mononuclear leukocytes: differences between respiratory syncytial virus and influenza viruses.

The ability of respiratory syncytial virus (RSV) to induce interferon production by human mononuclear leukocytes was compared with that of influenza viruses. Cell culture fluids were assayed for interferon activity 1, 3 and 7 days after exposure to RSV or to one of two subtypes of influenza A virus (H0N1 and H3N2). RSV induced interferon production inconsistently and in low titers. Varying the multiplicity of infection did not improve the ability of RSV to induce interferon production. In contrast, influenza viruses were effective inducers of interferon production. Seropositivity to the influenza virus strains was not associated with increased interferon titers. Interferon produced after exposure to RSV or to the influenza viruses was resistant to low pH treatment. The data suggest that interferon production may not be a major component of human immunological defense against RSV infection.     

Evaluation of a rapid test for detection of H5N1 avian influenza virus

The performance of H5 Dot ELISA, a rapid test for detection of avian H5N1 influenza virus, was evaluated using 30 H5N1 strains belonging to 10 major genetic groups of H5N1 influenza virus, 14 strains of non-H5N1 influenza virus and 652 field samples collected from healthy and diseased chickens from markets and poultry farms. The detection limit of the test for all 30 strains of H5N1 virus was < or = 0.1 hemagglutinin (HA) units and the test yielded a negative result when tested against 100 HA units of the non-H5N1 viruses. The test gave a positive result for 87 of the 106 poultry samples from which H5N1 virus was isolated by culture and 3 of 546 culture-negative poultry samples. Compared with virus culture, the overall prediction rate of the test was determined to be 96.6%; the positive prediction rate was 96.7% and negative prediction rate, 96.6%. The false positive rate was 0.5% and false negative rate 17.9%. Considering that the test is also convenient to use, it was concluded that H5 Dot ELISA is suitable for field use in the investigation of H5N1 influenza outbreaks and surveillance in poultry.     

Detection of influenza a subtypes in community-based surveillance

A rapid microtitre cell enzyme immuno assay (cell-EIA) was developed for the detection of influenza A subtypes in nasopharyngeal(NPS) swabs taken for surveillance. During the 1997/1998 influenza season in the United Kingdom, cell-EIA was compared to cell culture for the detection and typing of influenza A viruses in NPS obtained by sentinel general practitioners in community surveillance. The cell EIA can also be used to detect different influenza A subtypes (H3N2, H1N1, H5N3, H5N1, H7N7, and H9N2) and was used as a rapid detection assay for the screening of individuals returning from Hong Kong with influenza-like illness suspected to be due to H5N1 in 1997/98, providing a rapid, efficient, inexpensive method for the screening of influenza A cases during an outbreak or pandemic situation. The cell-EIA results reflected the results obtained by traditional virus culture within the age distribution of samples, clinical symptoms, and time between date of illness onset and sampling of cases, indicating its usefulness in surveillance of human and non-human influenza viruses. During two outbreaks of influenza in schools, Directigen Flu-A, a near patient test, the cell-EIA, and tissue culture were compared. The cell-EIA gave higher sensitivity and specificity (74% and 90%) than Directigen Flu-A (65% and 84.6%) in comparison with cell culture.