应用单克隆抗体酶免疫斑点试验检测抗传染性喉气管炎抗体

本文提出了硝酸纤维作固相载体，辣根过氧化物酶标记的抗传染性喉气管炎病毒（ＩＬＴＶ）的单克隆抗体（ＭｃＡｂ），邻苯二胺为底物，检测了ＩＬＴＶ抗体的免疫斑点试验方法（Ｄｏｔ－ＥＬＩＳＡ）。该方法较常规方法敏感，特异，省时，该方法的建立为鸡群疫监测，免疫鸡群抗体水平的检测提供了新的可靠方法。     

抗鸡传染性喉气管炎病毒单克隆抗体的研制及在诊断上的应用

鸡传染性喉气管炎王岗株病毒（ＩＬＴＶ）经ＳＰＦ鸡肾细胞增殖，差速离心及蔗糖密度梯度离心纯化，电镜观察。以纯化的病毒４次免疫ＢＡＬＢ／ｃ鼠，按常规方法进行细胞融合，采用有限稀释法克隆，经ＥＬＩＳＡ筛选出３株（８Ｅ２、１３Ｇ６、９Ｃ４）分泌抗ＩＬＴＶ特异ＭｃＡｂ的杂交瘤细胞。特异性试验表明它们与鸡的传染性支气管炎、痘病毒、新城疫病毒、马立克氏病病毒、白血病病毒及鸡肾细胞均无交叉反应。在获得的三株单抗建立单抗夹心－ＥＬＩＳＡ法基础上，首次建立了快速检测喉气管炎感染的ＥＬＩＳＡ试剂盒，对ＩＬＴＶ纯病毒的最小检出量为３１．０ｎｇ／ｍｌ病毒蛋白。以该试剂盒对黑龙江省哈尔滨地区、辽宁省沈阳、大连地区、山东省济南及上海等地６５６５份喉部株拭样品进行检测，共检出阳性１１５４头份。对部分ＥＬＩＳＡ阳性和阴性样品进行平行病毒分离，结果阳性符合率为１００％（１１２／１１２），阴性符合率为９５％（３８／４０）。研究表明，该试剂盒特异性强，重复性好。该方法的建立为鸡群疫病监测，免疫鸡群抗体水平检测提供了新的可靠方法。     

鸡传染性喉气管炎病毒单克隆抗体的建立及其应用

应用鸡传染性喉气管炎病毒（ＩＬＴＶ）作免疫原建立了８株分泌抗ＩＬＴＶ单克隆抗体（ＭｃＡｂ）的杂交瘤细胞株。这８株ＭｃＡｂ均具有荧光抗体的特性，没有中和病毒的能力，分别属于ＩｇＧ２ａ，ＩｇＧ３和ＩｇＭ，应用异硫氰酸荧光素标记ＭｃＡｂ，建立了直接荧光抗体试验，用其检测ＩＬＴＶ抗原与分离病毒的符合率为９２．８％。     

光生物素标记DNA探针检测传染性喉气管炎病毒感染

用光生物素标记４．３ｋｂ的传染性喉气管炎病毒（ＩＬＴＶ）ＤＮＡ片段作为探针，检测５只人工接种ＩＬＴＶ的ＳＰＦ鸡在不同时期采集的喉拭子样品或血清，并检测采自自然发病鸡群的喉试子样品。结果表明，用核酸探针点杂交方法在人工感染鸡喉气管中检出ＩＬＴＶ的时间为接种后６～１０天；该法敏感，特异，对诊断ＩＬＴＶ感染有实用价值，特别适用于进出口检疫和ＳＰＦ鸡群的监测。     

鸡传染性喉气管炎病毒单克隆抗体的特性和应用

应用鸡传染性喉气管炎病毒（ＩＬＴＶ）作免疫原建立８株分泌抗ＩＬＴＶ单克隆抗体（ＭｃＡｂ）的杂交瘤细胞株。这８个ＭｃＡｂ均具有ＦＡ特性、没有中和病毒能力，它们分别属于ｌｇＧ２ａ、ｌｇＧ３和ｌｇＭ。应用异硫氰酸荧光素（ＦＩＴＣ）标记ＭｃＡｂ，建立直接荧光抗体试验（ＤＦＡ），检测ＩＬＴＶ抗原与分离病毒，其符合率为９２．８％。ＤＦＡ具有准确、快速、方便等特点。     

鸡传染性喉气管炎病毒中国王岗株gX基因的克隆及鉴定

以ｐＵＣ１９质粒为载体克隆鸡传染性喉气管炎病毒（ＩＬＴＶ）中国王岗株的ＤＮＡ，构建了鸡传染性喉气管炎病毒ＤＮＡ的ＫｐｎⅠＤＮＡ文库。参考ＩＬＴＶ－ＳＡ２株ｇＸ基因的核酸序列，设计并合成了分别为１２ｂｐ和１３ｂｐ的１对引物。以ＩＬＴＶ中国王岗株ＤＮＡ为模板，用ＰＣＲ方法特异性地扩增出０．８４ｋｂ的ＩＬＴＶ－ｇＸ基因片段。以地高辛标记该０．８４ｋｂ的片段为探针，经Ｓｏｕｔｈｅｒｎ杂交从ＩＬＴＶ中国王岗株ＫｐｎⅠＤＮＡ文库中筛选出３个含５．２ｋｂ外源ＩＬＴＶＤＮＡ片段的ｇＸ基因阳性重组子。经酶切分析、Ｓｏｕｔｈｅｒｎ杂交、ＰＣＲ检测和该片段部分酶谱分析表明，ＩＬＴＶ中国王岗株ＤＮＡ５．２ｋｂ的ＫｐｎⅠ片段无论是片段大小还是酶切图谱均与ＩＬＴＶ－ＳＡ２株完全相同，而且Ｓｏｕｔｈｅｒｎ杂交和ＰＣＲ检测均为ｇＸ阳性，证明其中含有完整的ｇＸ基因     

鸡传染性喉气管炎ELISA诊断方法的研究──SPA—ELISA检测室内外ILTV病鸡效果

鸡传染性喉气管炎ＥＬＩＳＡ诊断方法的研究──ＳＰＡ—ＥＬＩＳＡ检测室内外ＩＬＴＶ病鸡效果黄承锋，吕敏娜，彭万强，孔庆飞，朱治远，幸桂香，杨海金（广东省农科院兽医研究所广州５１０６４０）用ＳＰＡ—ＥＬＩＳＡ诊断方法，在室内检测ＩＬＴＶ人工接种鸡胚尿囊膜...     

抗原捕获聚合酶链式反应检测鸡传染性喉气管炎病毒

用针对传染性喉气管炎病毒（ＩＬＴＶ）不同抗原表位的４株单抗（ＭｃＡｂ），混合包被Ｅｐｐｅｎ－ｄｏｒｆ管，捕捉ＩＬＴＶ，同时加入包含ＩＬＴＶＴＫ基因的两个引物，建立了能检测ＩＬＴＶ的抗原捕获聚合酶链式反应，得到了与预计大小一致的１２６２ｂｐ的ＰＣＲ产物，用ＴＫ基因内部酶切位点ＥｃｏＲＩ进行酶切，得到了预计大小为５９５ｂｐ和６６７ｂｐ的两个片段，证明了ＰＣＲ的产物的特异性，该方法的建立为传染性喉气管炎的快速确诊打下了基础，对于传染性喉气管炎的防制具有重要意义     

用单抗介导的荧光抗体技术检测鸡尿囊细胞内传染性支气管炎病毒的研究

用传染性支气管炎病毒（ＩＢＶ）Ｈ１２０、Ｈ５２、Ｍ４１、ＡＲＫ、澳大利亚Ｔ株、野外分离株ＲＳ、ＲＹ及鸡新城疫病毒（ＮＤＶ）、鸡传染性法氏囊病毒（ＩＢＤＶ），鸡传染性喉气管炎病毒（ＩＬＴＶ）、减蛋综合症病毒（ＥＤＳＶ）等分别接种９日龄ＳＰＦ鸡胚，３７℃孵育４８小时后，将其尿囊液离心，沉淀用ＰＢＳ悬浮，涂片，用抗ＩＢＶ单抗ＭＣ作一抗、进行间接荧光抗体检测。结果：Ｈ１２Ｏ、Ｈ５２、Ｍ４１“ＡＲＫ、Ｔ株及ＲＳ、ＲＹ均显阳性，而ＮＤＶ、ＩＢＤＶ、ＩＬＴＶ、ＥＤＳＶ均为阴性。结果表明、用此法检测鸡胚尿囊液中ＩＢＶ．具有快速、敏感、特异的优点。     

应用间接免疫荧光法检测禽网状内皮组织增生病病毒抗体的研究

用禽网状内皮组织增生病病毒（ＲＥＶ）感染ＳＰＦ鸡胚次代成纤维细胞涂片为抗原,建立了检测ＲＥＶ抗体的间接免疫荧光法（ＩＦＡ）。确定了待检血清稀释度１∶６４和兔抗鸡ＩｇＧ荧光抗体的稀释度１∶３２的工作浓度。应用该ＩＦＡ方法对人工感染ＲＥＶ的２０只３０日龄ＳＰＦ鸡进行了检测,接种后４天时均呈阴性反应,７天时８只鸡呈阳性反应,１４天２０只全部呈阳性的反应。通过对ＮＤＶ、ＩＢＤＶ、ＡＬＶ、ＭＤＶ、ＣＩＡＶ、ＡＩＶ等标准阳性血清的交叉试验,证明该方法特异性强。应用该ＩＦＡ方法对我国辽宁、山东、黑龙江省部分鸡群进行ＲＥＶ抗体检测,证明该方法特异性强、敏感性高,适于在生产中推广应用。     

Seroprevalence of avian influenza virus, infectious bronchitis virus, reovirus, avian pneumovirus, infectious laryngotracheitis virus, and avian leukosis virus in Nigerian poultry

Eight poultry farms in Nigeria, including chickens from nine breeder, 14 broiler, 28 pullet, 11 layer, and three cockerel flocks, were tested for antibody seroprevalence to the following poultry viruses of potential economic importance: infectious bronchitis virus (IBV), avian reovirus, avian pneumovirus (APV), infectious laryngotracheitis virus (ILTV), avian influenza virus (AIV), and avian leukosis virus (ALV). Serum samples were collected between 1999 and 2004 and were tested for antibodies using commercial enzyme-linked immunosorbent assay (ELISA) kits. Seroprevalence was very high for IBV (84%); intermediate for reovirus (41%), APV (40%), and ILTV (20%); and very low for ALV (<5%) antibodies. By commercial ELISA, the seroprevalence of antibodies against AIV was, in some flocks, up to 63%. However, more specific assays did not confirm AIV antibodies, indicating that all flocks tested were free of avian influenza antibodies. Birds seemed to be first infected by IBV (at about 7 wk of age), then by reovirus at 12 wk, before they became infected by APV (week 25) and ILTV (week 30). This is the first report of serological evidence of the above viruses in West Africa. Further studies are necessary to assess economic losses due to these avian viruses and the costs and benefits of countermeasures.     

禽传染性喉气管炎病毒gD蛋白单克隆抗体的制备

为制备抗鸡传染性喉气管炎病毒(ILTV)糖蛋白gD的单克隆抗体(MAb),本研究通过原核表达gD重组蛋白,纯化后免疫6周龄雌性BALB/c小鼠,经细胞融合筛选获得一株稳定分泌抗ILTV gD蛋白的杂交瘤细胞株,MAb亚型经鉴定为IgG1,轻链为κ链。Western blot结果显示,这株杂交瘤细胞分泌的MAb能够识别ILTV。ILTV gD蛋白的MAb的制备,为ILTV检测方法的建立奠定了基础。     

应用改良阻断ELISA检测禽网状内皮组织增殖病血清抗体

应用禽网状内皮组织增殖病病毒纯化抗原和抗ＲＥＶ单克隆抗体建立了改良阻断ＥＬＩＳＡ用于鸡血清中ＲＥＶ抗体检测，并对北京地区鸡群中随机采样的３６份血清样本进行了检测，阳性率为５．６％。与间接ＥＬＳＩＡ的检测结果进行了统计学比较，两种方法的阳性率无显著差异。结果表明本试验所建立的改良阻断ＥＬＩＳＡ可以用于鸡群ＲＥＶ感染的血清学调查。     

The application of the ELISA to the diagnosis and control of avian encephalomyelitis

An ELISA for measuring serum antibody against avian encephalomyelitis virus (AEV) was evaluated for its application to the diagnosis and control of avian encephalomyelitis (AE). A scoring system was developed for this ELISA (AE ELISA-Index) so that the overall level of antibody in the flock could be presented in a single, convenient number. During suspected outbreaks of disease thought to have been caused by AEV infection, the AE ELISA-Index increased in sequential serum samples. High levels of antibody against AEV were measured in 13 flocks experiencing egg productivity problems. Variable levels of antibody activity against infectious bronchitis virus (IBV) were also observed in 11 of these flocks. The AE ELISA-Index was correlated with the embryo susceptibility test. Application of the AE ELISA has indicated that natural exposure to the virus does not occur in all flocks, and vaccination failures were detected sufficiently early for revaccination to be administered before the onset of lay.     

Expression of infectious laryngotracheitis virus glycoproteins in Escherichia coli and their application in enzyme-linked immunosorbent assay

Three glycoproteins of infectious laryngotracheitis virus (ILTV), gC, gE, and gp60, were expressed in Escherichia coli as fusion proteins with a 6-histidine tag at their amino termini. The proteins expressed, designated as r-gC, r-gp60, and r-gE, all retain their antigenicity, as revealed by Western blot with chicken antiserum against ILTV. However, only r-gp60 and r-gE, but not r-gC, were found to be soluble. The soluble r-gp60 and r-gE were purified by a nickel column and then used as the enzyme-linked immunosorbent assay (ELISA) antigen for detecting ILTV-specific antibodies. The diagnostic potential of r-gE and r-gp60 ELISA was assessed with the use of sera prepared from vaccinated or unvaccinated chickens of either specific-pathogen-free (SPF) or field origins. The result shows that r-gp60 and r-gE ELISA could discriminate vaccinated SPF chickens from unvaccinated ones 2 wk postvaccination. Moreover, r-gp60 and r-gE ELISA could also discriminate vaccinated field flocks from unvaccinated ones. This result indicates that r-gp60 and r-gE might serve as an alternative ELISA antigen for detecting ILTV-specific antibodies. Moreover, r-gp60 or r-gE ELISA might play an important role in the eradication of infectious laryngotracheitis (ILT) in the future when the gp60- or gE-deleted marker vaccine of ILT is available.     

Field basis evaluation of Eimeria necatrix-specific enzyme-linked immunosorbent assay (ELISA) for its utility in detecting antibodies elicited by vaccination in chickens

Eimeria necatrix-specific ELISA, using a recombinant antigen (the cDNA-clone NP19 expressing protein), was utilized to detect antibodies against E. necatrix in breeder pullet flocks that had previously received an attenuated live vaccine to E. necatrix. Vaccinated flocks were discriminated significantly from non-vaccinated flocks by their antibody titers and antibody positive rates at 30-55 days post-vaccination. In addition, E. necatrix-oocysts were confirmed in fecal samples of vaccinated flocks using PCR in the case where the antibody positive rates rose. These findings implied that the vaccination prompted repeated infections, and consequently the chickens generated antibodies and secured their protection against virulent field-E. necatrix. Therefore, the ELISA was suggested to be a useful tool to estimate the immune state of chickens as a result of vaccination with a live E. necatrix-vaccine.     

Detection of antibodies against reticuloendotheliosis viruses by an enzyme-linked immunosorbent assay

A microplate indirect enzyme-linked immunosorbent assay (ELISA) for antibodies against reticuloendotheliosis virus (REV) was consistently more sensitive than indirect immunofluorescent-antibody tests. Limits of antibody detection were comparable to those obtained in virus neutralizations. Detection of REV-infected chickens long after infection and after immunofluorescent antibody has waned makes ELISA especially suitable for screening chicken flocks.     

Detection of antibodies against serotypes 1 and 2 infectious bursal disease virus by commercial ELISA kits

Two distinct serotypes of infectious bursal disease virus (IBDV) are recognized in chicken and turkey flocks in the United States. Serologic testing of chicken flocks for serotype 1 viruses is routinely performed to monitor disease status and vaccination. Earlier studies indicated that enzyme-linked immunosorbent assay (ELISA) test detects antibodies to both serotypes of the virus, while the virus neutralization (VN) test is serotype specific. It is useful to evaluate currently available commercial ELISA kits for their ability to differentiate between antibodies elicited by the two serotypes. Three trials were performed in which chickens were orally inoculated with either a high or a low dose of serotype 1 STC or serotype 2 OH strains of IBDV. Sera collected at 0, 7, 14, and 21 days from these chickens and antisera procured from naturally infected broiler (n=20) and layer (n=30) flocks were tested with five different commercial ELISA kits and by VN. All ELISA kits detected different levels of antibodies elicited against serotype 1 of the virus and moderate and high levels of antibodies against serotype 2 virus. A correlation existed between the ELISA and the VN titers of experimentally infected chickens. All serum samples tested from the commercial layer flocks and 65% of the broiler flocks had antibodies against the OH strain. However, no correlation between the VN titers and ELISA titers was observed for the commercial broilers and layers sera by the majority of the kits. The results indicated that currently available commercial ELISA kits detect antibodies elicited by the two serotypes of IBDV. Hence, the prevalence of serotype 2 antibodies in the flocks should be considered while determining antibody profiles of the flocks against serotype 1 viruses.