检测鸡传染性支气管炎病毒抗体的三种血清学方法的比较

应用酶免疫吸附试验（ＥＬＩＳＡ），琼脂扩散沉淀试验（ＡＧＰ）和鸡气管环培养中和试验（ＳＮ ｉｎＴＯＣｓ）三种常规血清学方法对实验鸡血样的鸡传染性支气管炎病毒抗体进行了检测。从实验鸡血样的检测结果表明，ＥＬＩＳＡ和气管环中和灵敏度较好，而ＡＧＰ的灵敏度相对较差，但三者均有较好的特异性。     

检测鸡慢性呼吸道病抗体ELISA方法的建立

用败血支原体（ＭＧ）Ａ５９６９株制备ＥＬＩＳＡ抗原,与抗鸡ＩＧ单抗ＩＢ７酶结合物建立了检测鸡血清抗体水平的间接ＥＬＩＳＡ方法,交叉试验、阻断试验、重复性试验等表明该方法重复性好、特异性强、灵敏度高。确立了将鸡血清６４倍稀释监测ＥＬＩＳＡ效价（ＥＴ）的回收方程ｙ＝１．３８３＋０．２２４ｘ,可用于定量测定,血凝抑制试验（ＨＩ）与ＥＬＩＳＡ比较试验表明,ＥＬＩＳＡ法比ＨＩ试验敏感性高４倍以上。     

用抗传染性氏囊病毒单克隆抗体建立夹心阻断ELISA检测鸡血清抗体及 …

用酶标记抗传染性法氏囊病毒（ＩＢＤＶ）单克隆抗体，建立夹心阻断ＥＬＩＳＡ，检测ＩＢＤＶ鸡血清抗体。用Ｄ７８细胞毒免疫２４日龄的雏鸡，每周采血一次，共４次，用夹心阻断ＥＬＩＳＡ、微量细胞中和试验（ＶＮ）、琼脂扩散试验（ＮＧＰ）检测鸡血清抗体，结果表明：夹心阻断ＥＬＩＳＡ同ＶＮ之间具有较高的相关性（ｒ＝０．８１２６），与ＡＧＰ的相关性较低（ｒ＝０Ｘ．７５７５）。     

快速检测鸡新城疫病毒的聚乙二醇单抗夹心ELISA试验的建立和应用

以抗鸡新城疫病毒（ＮＤＶ）单抗夹心ＥＬＩＳＡ试验为基础，在６０００，建立了ＰＥＧ－ＥＬＩＳＡ法，使用此法检测临诊样品，与单抗夹心ＥＬＩＳＡ相比，时间缩短７０分钟且提高了ＯＤ４９０值，易于识别。结果表明，ＰＥＧ－ＥＬＩＳＡＩ法具有实际应用价值。ＰＥＧ能加强抗原－抗体反应的速率和强度，这种效应在固相夹心ＥＬＩＳＡ第二步表现尤其明显。ＰＥＧ的这种非特异性效应对于检测其它抗原或抗体的ＥＬＩＳＡ试验可能具有     

抗鸡IgG重链单克隆抗体的制备与应用

以提纯鸡ＩｇＧ做抗原免疫Ｂａｌｌ／ｃ小鼠，取鼠细胞在ＰＥＧ１０００作用下与小鼠骨髓细胞（Ｓｐ２／ｏＡｇ１４）融合，采用间接免疫荧光（ＩＦＡ）和酶联免疫吸附试验（ＥＬＩＳＡ）检测上清抗体，阳性孔经有限稀法进行细胞克隆，共获得了７株分泌抗鸡ＩｇＧ单克隆抗体的杂交瘤细胞（２Ｈ８、４Ｄ８、４Ｄ８、１Ｂ７、２Ａ７、２Ｂ３、１Ｇ１２、３Ｄ１２）将这些细胞分别接种间系小鼠制备出腹水抗体，ＥＬＩＳＡ效价可达１０＾     

应用ELISA和AGP检测鸡白血病病毒的比较

应用ＥＬＩＳＡ和ＡＧＰ检测羽随和蛋清中鸡白血病病毒ＡＬＶ，样品采用同一品系的普通原种鸡群。当用此二种方法同时检测同一种样品中ＡＬＶ的群特异性抗原时发现，ＥＬＩＳＡ的阳性率高于ＡＧＰ，ＥＬＩＳＡ显示出较高的敏感性。当同时用ＡＧＰ检测羽髓样品和用ＥＬＩＳＡ检测蛋清样品来鉴定同一鸡群中潜在的ＡＬＶ感染母鸡时，结果表明ＥＬＩＳＡ的阳性率高于ＡＧＰ，而且有一定比例的ＡＧＰ阳性鸡用ＥＬＩＳＡ检测时为阴性，因此     

间接ELISA检测鸭肝炎病毒抗体的研究

以蔗糖密度梯度离心法纯化的病毒作为包被抗原，建立了检测鸭肝炎病毒（ＤＨＶ）抗体的间接ＥＬＩＳＡ方法。经特异性及重复性试验，效果良好。ＥＬＩＳＡ效价与琼扩、中和效价存在平行关系。经ＥＬＩＳＡ检测，１日龄雏鸭免疫后，４日龄可检出ＥＬＩＳＡ抗体，１０日龄达到峰值。ＤＨＶ高免血清在雏鸭体内作用维持时间为１０ｄ左右。攻毒保护试验表明，攻毒前雏鸭的血清抗体水平与攻毒后雏鸭存活率具直接相关性。     

间接酶联免疫吸附试验检测禽流感抗体的最佳工作条件

禽流感病毒（ＡＩＶ）感染的鸡胚尿囊液经差速离心后,再经蔗糖密度梯度离心,提纯ＡＩＶ,纯化的ＡＩＶ经ＮＰ４０处理并反复冻融,即为ＡＩＥＬＩＳＡ抗原,用该抗原包被聚苯乙烯微量反应板。将健康鸡ＩｇＧ提纯后免疫兔,制备兔抗鸡ＩｇＧ,用过碘酸钠法制备辣根过氧化物酶标记的兔抗鸡ＩｇＧ。确立了间接酶联免疫吸附试验（ＥＬＩＳＡ）检测禽流感抗体的最适工作条件,即：抗原包被浓度１．９～３．８μｇ／ｍｌ,每孔１００μｌ,４℃冰箱过夜;用含０．５％牛血清白蛋白（ＢＳＡ）的磷酸盐缓冲液,３７℃封闭６０分钟;待检血清最佳稀释度为１８０～１６４０,作用６０分钟;酶标抗体作１２０００稀释,作用６０分钟。根据对５２份ＳＰＦ鸡血清的检测结果制定了判定标准。     

异源抗原在建立ELISA检测传染性法氏囊病毒抗体中的应用

本文报告采用ｖｅｒｏ细胞增殖的ＩＢＤＶ抗原建立了间接酶联免疫吸附试验（ＥＬＩＳＡ），用于定量检测鸡传染性法氏囊病毒（ＩＢＤＶ）抗体。该法快速、敏感性高、特异性强、重复性好。同时，通过３０份血清样品ＥＬＩＳＡ效价（ＥＴ）的对数值（ｌｏｇＥＴ）与血清Ｐ／Ｎ值（待检血清ＯＤ值与阴性血清ＯＤ值之比）的线性回归分析，得直线方程ｙ＝３．０５８９＋０．０７３９ｘ（ｒ＝０．９１７４），从而血清样品的ＥＴ可通过血清单一稀释度的Ｐ／Ｎ值来计算。用不同来源抗原作ＥＬＩＳＡ表明，从ｖｅｒｏ细胞增殖的抗原比从鸡胚成纤维（ＣＥＦ）细胞增殖的抗原可提高检测血清ＯＤ值近２０％，表现出异源抗原具有更高的特异性     

分泌抗鸡Ig单抗杂交瘤细胞系的建立与单抗生物学特性的鉴定

从传染性法氏囊病病毒（ＩＢＤＶ）单克隆抗体（ＭｃＡｂ）杂交瘤细胞系１Ｄ１０、１Ｇ１中得到了３株能稳定分泌抗鸡免疫球蛋白（Ｉｇ）ＭｃＡｂ的杂交瘤细胞系１Ｂ７、１Ｄ７、３Ｇ６。其抗体类和亚类均属ＩｇＧ２ｂ，腹水的ＥＬＩＳＡ效价≥１∶２５６００，琼扩效价为１∶８～１∶１６。３株ＭｃＡｂ能与鸡血清中的Ｉｇ出现沉淀反应，琼扩在２４ｈ以内出现清晰的沉淀线，而不能和鸭、鸽、鹌鹑等禽类及异种动物血清出现沉淀线。纯化的鸡ＩｇＧ、ＩｇＭ经ＳＤＳ－ＰＡＧＥ后，分别用纯化并经辣根过氧化物酶（ＨＰＲ）标记的１Ｂ７、１Ｄ７、３Ｇ６单抗酶结合物进行免疫印迹试验证明，３株单抗识别的均为ＩｇＧ、ＩｇＭ分子的轻链     

A blocking ELISA for the detection of specific antibodies to bovine respiratory syncytial virus

A blocking enzyme-linked immunosorbent assay (ELISA) has been adapted to detect specific antibodies in bovine sera to respiratory syncytial virus using a horseradish peroxidase-labeled monoclonal antibody to the fusion protein of the virus. This assay plus an indirect blocking ELISA and indirect ELISA were used to detect antibodies to the bovine respiratory syncytial virus (BRSV) in 159 field-origin bovine sera. Results of these assays were compared with serum antibody titers measured by the serum neutralization (SN) test. Over a 56-day period, the mean neutralization titers and the mean delta absorbance values for the blocking ELISA, on the same sera, showed similar declines. However, the calculated correlation coefficients between mean SN titer and mean absorbance value for the blocking ELISA of the individual sera ranged from -0.2 to -0.5 depending on the source of sera. Similar values were obtained whether using crude or purified viral antigen in the assays. Corresponding calculated correlation coefficients were generally higher for the indirect blocking ELISA or indirect ELISA than for the blocking ELISA. The blocking ELISA was between 70 and 64% as sensitive as the serum neutralization test with a specificity of 100 or 90% using the crude and purified viral antigen, respectively. The indirect blocking ELISA and indirect ELISA had similar calculated sensitivities and specificities. The blocking ELISA was faster to run than either of the other ELISA's or the neutralization test. Further, nonspecific background absorbance was obviated because the blocking ELISA detects antibodies to 1 specific viral protein, the fusion protein. These studies suggest that the blocking ELISA should be useful as a serological test for BRSV antibodies.     

Enzyme-linked immunosorbent assay (ELISA) using staphylococcal protein A for the measurement of rabies antibody in various species

An ELISA was developed using staphylococcal protein A linked with horseradish peroxidase for detecting IgG antibody of rabies virus in human and carnivore sera (80 human, 270 fox, 40 cat, 35 marten, 5 badger and 4 polecat sera were tested in the present work). In comparison with the serum neutralization (SN) test in cell culture, close overall agreement was obtained particularly in human and cat sera (97.5%). Two post-vaccination human sera were found positive with ELISA values of 2.16 and 2.65 IU/0.2 ml, but with SN titers less than 1:10. All prevaccination human sera were found negative by both tests. Regression analysis on 30 post-vaccination human sera revealed better correlation between ELISA and SN test at a serum dilution of 1:100 than at lower serum dilutions of 1:80 or 1:20. The correlation coefficient (r) was 0.73 (p less than or equal to 0.0001).     

Labeled avidin-biotin enzyme-linked immunosorbent assay for detecting antibody to infectious laryngotracheitis virus in chickens

A labeled avidin-biotin enzyme-linked immunosorbent assay (LAB-ELISA) for detecting antibody to infectious laryngotracheitis (ILT) virus in chicken sera was developed and compared with ordinary ELISA. Purified ILT virus, biotin-labeled anti-chicken IgG rabbit IgG conjugate, and horseradish-peroxidase-labeled avidin were used in the LAB-ELISA. When sera from farm chickens were tested by serum neutralization (SN) and two kinds of ELISA, the correlation rate between SN and LAB-ELISA was 50/50 (100%), and that between SN and ordinary ELISA was 39/50 (78%). In LAB-ELISA, all of the sera that were antibody-negative by SN had low absorbance (A) values (below 0.05), and the A values were closely correlated with the SN indexes. In ordinary ELISA, however, the sera antibody-negative by SN had various A values ranging from 0.06 to 0.32. LAB-ELISA had much lower nonspecific reactions than ordinary ELISA against sera from ILT-negative chickens, even when chickens were 30 weeks old. ILT antibody production after ILT vaccination could be detected by LAB-ELISA. A values peaked 5 weeks postinoculation and were maintained for 17 weeks.     

Comparison of precipitin antibodies and virus-neutralizing antibodies to infectious bursal disease virus

Three hundred twenty-two serum samples from commercial pullets and multiplier breeders were analyzed for agar-gel precipitin (AGP) antibodies and virus-neutralizing (VN) antibodies to infectious bursal disease virus. Two hundred thirty-four of these sera were AGP-positive, and 88 were AGP-negative. The geometric mean of the reciprocal of the VN titers for the AGP-positive sera was 208.7, and 232 (99.1%) had a VN titer of 1:16 or greater. In contrast, the geometric mean of the reciprocal of the VN titers for the AGP-negative sera was 6.1, but 53 (60.2%) had a VN titer ranging from 1:4 to 1:256. When the AGP test was compared with the VN test, the sensitivity and specificity, respectively, of the AGP test were 81.5% and 100%.     

An enzyme-linked immunosorbent assay for the detection of bovine antibodies to vesicular stomatitis virus

An indirect enzyme-linked immunosorbent assay (ELISA) was developed to detect bovine antibody to vesicular stomatitis virus (VSV). Serum samples from cows experimentally infected with the New Jersey serotype of VSV (VSV-NJ) were assayed by the ELISA and serum-neutralization (SN) assay. The ELISA was as sensitive as the SN assay in detecting bovine antibody to VSV. The correlation between SN titers and ELISA values at absorbance at 405 nm was statistically significant. The ELISA was not specific for VSV-NJ, however, and could detect serum samples positive to the Indiana serotype of VSV that had SN titers of greater than or equal to 480. Nonspecific reactions were due to cross-reactive group-specific viral proteins that are shared by both serotypes. The cross-reactivity allows the use of a single rapid test in identifying both serotypes of VSV from the other exotic vesicular diseases, especially foot-and-mouth disease. The ELISA titers of serum samples positive for VSV-NJ were comparable with the corresponding SN titers of each sample. The sensitivity, rapidity, and ease of the ELISA system and the use of a single test in identifying both serotypes of VSV from the other exotic vesicular diseases make this ELISA suitable as a rapid diagnostic assay for VS.     

Rapid enzyme-linked immunosorbent assay for detecting antibodies to canine parvovirus

A rapid screening assay for determining antibodies to canine parvovirus in dog serum using monoclonal antibodies and enzyme-linked immunosorbent assay (ELISA) technology was developed. The ELISA could be read visually, and the results correlated well with serum neutralization (SN) and hemagglutination inhibition (HI) titers. Sera with SN less than or equal to 1:4 or HI less than or equal to 1:10 had an 87.9% correlation with ELISA and sera with SN greater than or equal to 1:64 or HI greater than or equal to 1:80 had a 94.4% correlation. The assay took only 10 to 15 minutes to perform and did not require specialized equipment. The ELISA should be useful in monitoring dogs for the presence of maternal antibodies against parvovirus and for determining seroconversion after vaccination.     

An enzyme-linked immunosorbent assay for the detection of antibody to avian reovirus by using protein sigma B as the coating antigen

An enzyme-linked immunosorbent assay using the expressed protein sigma B as the coating antigen (sigma B-ELISA) for detecting antibody to avian reovirus (ARV) in chickens was developed and compared with a conventional ELISA. Both ELISA s and a serum neutralisation (SN) test were used to test the sera from experimentally vaccinated and farm chickens. The sigma B-ELISA could clearly distinguish the SN-positive and -negative sera in 38-week-old chickens. The correlation rate between SN and a sigma B-ELISA was 100 per cent (65/65), and that between SN and conventional ELISA was 84 per cent (55/65). With the sigma B-ELISA, all SN-negative sera had low absorbance values (below 0.06), and the absorbance values correlated closely with the SN titres. However, the sera which were antibody-negative by SN had various absorbance values, ranging from 0.07 to 0.39 in the conventional ELISA. Hence, the sigma B-ELISA had lower non-specific binding reactions than the conventional ELISA against sera from ARV -negative birds. Antibody against ARV could be detected by sigma B-ELISA after vaccination. Absorbance values peaked 4 weeks after vaccination at 2 weeks of age and were maintained until the birds were 27 weeks old. The results suggest that the presence of antibody against viral protein sigma B in birds may be used as a good indicator by the sigma B - ELISA for detecting immune status of a chicken flock or to detect chickens infected with ARV.     

应用琼脂免疫扩散试验检测猪伪狂犬病抗体的研究

建立了ＡＧＩＤ用于猪伪狂犬病（Ｐｓｅｕｄｏｒａｂｉｅｓ,Ｐｒ）的诊断。对９８份被俭血清的ＡＧＩＤ结果与ＳＮ结果比较,当ＳＮ滴度大于１：８时两者的阳性检出符合率为１００％,ＳＮ滴度小于或等于１：８时,两者的阳性检出符合率为８７．５％,ＡＧＩＤ和ＳＮ总的阳性符合率为９４．４％,结果表明,ＡＧＩＤ对Ｐｒ可进行特异性诊断,流行病学调查和免疫动态监测。     

A comparative evaluation of two sensitive serum neutralization tests for bovine herpesvirus-1 antibodies.

Two sensitive serum neutralization (SN) tests for the detection of antibodies to bovine herpesvirus-1 (BHV-1) in bovine sera were evaluated. Both SN tests used a 24 h incubation of test sera with 100 CCID50 of BHV-1 before the addition of susceptible cells. The tests differed in the presence (C test) or absence (D test) of complement and were compared with a standard 1 h incubation SN test and the enzyme-linked immunosorbent assay (ELISA). Although the mean titer of the C test was twofold higher than the mean titer of the D test for 310 sera, the number of samples which were negative was not significantly different between tests. For 100 sera from herds with known reactors, which were negative in a 1 h incubation SN test, 32% tested positive in the C and D tests. Other investigations, including Western immunoblotting and radioimmune precipitation, suggest that the 24 h incubation tests produce some false positive results. In contrast, the 1 h incubation SN test and, to a much lesser extent, the ELISA appear to produce some false negative results. The C test was more sensitive than the D test for detecting an early immune response after experimental infection.     

Enzyme immunoassay studies on the serological response of turkeys to hemorrhagic enteritis virus

An enzyme-linked immunosorbent assay (ELISA) was developed for the detection of antibodies in turkey serum to hemorrhagic enteritis virus. The ELISA antigen was extracted from turkey spleens and partially purified with fluorocarbon. Antibodies were demonstrated in serum samples of breeding and meat flocks that had been naturally exposed to infection. These samples were also examined in parallel by agar-gel precipitin (AGP); most of the sera were AGP-positive. ELISA, however, was more sensitive in detecting antibodies in day-old sera that were AGP-negative. The passively acquired antibodies were no longer detected by 4 weeks of age. A brisk but short-lived secondary response was detected by ELISA in the sera of turkeys immunized with beta-propiolactone-inactivated extract of infected spleens.