免疫诊断用羧化聚苯乙烯载体微球的制备

采用“无乳化剂”乳液聚合法合成了表面“清洁”的聚苯乙烯-丙烯酸胶乳微球,并对影响微球粒径、单体转化率的诸因素进行了探讨.结果表明:所合成的胶乳微球呈圆球状,粒径大小可控制在0.1～0.6μm范围内,且单分散性良好.调节单体的含量和亲疏水性可控制微球粒径和表面性能.将此微球分别与血清抗原共价偶联,其抗原效价高于有乳化剂的胶乳微球.这表明免疫化的无乳化剂微球具有良好的生物特异性.     

ABC-ELISA法检测犊弓首蛔虫IgG抗体实验研究

首次以动物为模型,应用 ABC-ELISA 法对家兔血清中犊弓首蛔虫 IgG 抗体进行了测试研究。实验中对犊弓首蛔虫的成虫体壁抗原、体腔液抗原、生殖器官抗原、虫卵抗原、幼虫抗原进行了比较研究,结果显示:幼虫抗原对血清检测的 P/N 值及对被检血清的检出率最高,而检测对照组血清未出现假阳性反应.由此表明,幼虫抗原是最敏感和特异的抗原.在检测方法上,ABC-ELISA 法对被检血清的检出率为96.62%。常规 ELISA 法和 IHA 法的检出率分别为90%和56.67%。3种方法检测对照组血清未出现假阳性反应;在抗体检测滴度上,ABC-ELISA 法比常规 ELISA 法高1～4倍,比 IHA 法高4～128倍.经统计处理,ABC-ELISA 法比常规 ELISA 法敏感1.21倍,比 IHA 法敏感33.76倍.在特异性实验中,用 ABC-ELISA 法检测家兔血清中犊弓首蛔虫 IgG 抗体,与实验家兔乳突类圆线虫和肝片吸虫阳性血清均未出现交叉反应,表明该法检测犊弓首蛔虫抗体特异性良好.另外,对4份血清多次重复检测结果,批内重复和批间试验 OD 值变异系数不超过10%,表明该法稳定性良好.实验结果表明,ABC-ELISA 法具有敏感性高,特异性强,并有较好的稳定性,可用于犊弓首蛔虫抗体的检测,故该法的建立无疑具有理论和实践意义.     

几种免疫标记检测法对炭疽菌诊断的比较研究

本文采用免疫荧光标记技术、免疫酶标技术和葡萄球菌蛋白A(Staphylococcal Protein A.SPA)协同凝集反应对炭疽杆菌进行了快速诊断比较试验,结果均收到比较满意的效果,但以用SPA协同凝集反应,更表现出快速、简便、敏感、特异等优点。     

应用免疫印迹法检测异尖线虫病人及实验动物血清中的抗体

本实验应用简单异尖线虫幼虫制备的全虫抗原及分泌－代谢抗原，以免疫印迹法检测异尖线虫病人血清及人工感染实验动物血清中的抗体。在７份病人阳性血清及重复经口感染异尖线虫幼虫的大鼠血清中，均查出识别Ｐ４６蛋白成分的特异抗体。而在２５份蠕虫病人血清中（包括蛔虫病、犬弓蛔虫病、丝虫病、旋毛虫病、肝片吸虫病等）未出现此特异抗体。Ｐ４６抗原成分显然是异尖线虫病的特异抗原成分。免疫印迹法用来诊断慢性异尖线虫病是一种特异性较强的方法。     

兔脑炎微孢子虫病的免疫学研究进展

兔脑炎微孢子虫病是由兔脑炎微孢子虫引起的一种隐性、慢性感染或临床经过的人畜共患的原虫病。近十余年来 ,出现大量有关兔脑炎微孢子虫引起艾滋病患者致死性临床感染的报道 ,此病日益引起医学界的广泛关注和重视。就兔脑炎微孢子虫病的免疫学检测方法、细胞免疫应答、感染兔脑炎微孢子虫后人及动物的免疫学比较的研究状况进行了综述。     

Canine heterophilic antibodies as a source of false-positive B-type natriuretic peptide sandwich ELISA results

BACKGROUND: Interference by heterophilic antibodies is a well-known cause of false-positive sandwich ELISA results in human medicine. They are considered rarely in veterinary species and have not been characterized but could become important as newer, highly sensitive sandwich immunoassay technologies are developed. OBJECTIVES: The goals of this study were to use a B-type natriuretic peptide (BNP-32) sandwich ELISA to determine the effect of heterophilic antibodies on test performance; to characterize canine heterophilic antibodies; and to develop and test a method for heterophilic antibody removal. METHODS: A sandwich ELISA was developed using a mouse IgG(1)K monoclonal and a rabbit polyclonal antibody to two synthetic peptides of canine BNP-32. The effects on false-positive results of heterophilic antibody depletion and blocking by various techniques were compared. The titers of canine heterophilic antibodies were compared with various blood antigens from other species and the relative amount of canine IgG was compared with that of IgM heterophilic antibody. RESULTS: Heterophilic antibodies in dog plasma were shown to be capable of causing false-positive ELISA results. They reacted with blood proteins from a variety of animal species at relatively low titers and consisted of both IgG and IgM. Protein A agarose antibody precipitation, in conjunction with mouse IgG(1)K blocking antibody, was effective in eliminating false-positive sandwich ELISA results while retaining adequate test performance. CONCLUSIONS: Canine heterophilic antibodies can interfere with sandwich ELISA assays and cause false-positive test results. An effective technique for their removal that has a potentially broad application was developed, and allows measurement of canine blood constituents at low picomolar concentrations.     

重组CE18蛋白在绵羊绦虫蚴病诊断上的应用

 【目的】探讨细粒棘球蚴CE18重组蛋白作为绦虫蚴病免疫诊断抗原的应用价值,为筛选绦虫蚴病血清学诊断抗原提供依据。【方法】应用棘球蚴CE18重组抗原建立间接ELISA方法,分别对18份脑多头蚴、15份细颈囊尾蚴、19份棘球蚴感染绵羊血清及194份棘球蚴病疫区绵羊血清和13份健康羊血清进行检测,通过显著性差异分析评价CE18蛋白作为诊断抗原的意义。同时,应用生物学软件对CE18抗原蛋白同源序列进行分析,进一步从分子水平上提示CE18蛋白作为绦虫蚴病诊断抗原的依据。【结果】序列分析表明棘球蚴CE18蛋白基因为多种绦虫如泡状带绦虫、多头带绦虫、猪带绦虫等的共有序列,其蛋白质氨基酸序列相似性很高,不同种属之间高达99%,从分子水平上表明CE18蛋白为带绦虫蚴共同抗原成分之一。重组抗原CE18-ELISA方法检测绵羊血清抗体水平显示：脑多头蚴病、细颈囊尾蚴病、棘球蚴病和棘球蚴病疫区血清的阳性率分别为38.89%、73.33%、100%和76.14%,而对照组血清为阴性反应。【结论】CE18重组蛋白可作为绵羊棘球蚴病和细颈囊尾蚴病血清学诊断抗原,用于畜群活体检疫初筛试验。     

Diagnosis of Rinderpest in Tanzania by a Rapid Chromatographic Strip-test

A simple chromatographic strip-test based on Clearview technology, is under development as a pen-side test for the detection of rinderpest antigen in eye swabs taken from cattle in the field. An outbreak of rinderpest occurred in the northern zone of Tanzania from late February to June 1997. The affected cattle exhibited very mild clinical signs, which made clinical diagnosis difficult. One hundred and seven eye swabs were collected from cattle suspected of infection with rinderpest. These were tested in the field using a prototype of the pen-side test and 13 (12.15%) of the samples were found to be positive for the presence of rinderpest antigen. These were confirmed by ICE. The positive cases were predominantly found in the Ngorongoro district. This demonstrates the usefulness of such a simple, rapid pen-side diagnostic assay, particularly when clinically `mild' strains of rinderpest are present.     

大片吸虫分泌排泄抗原的分析

取广西牛源大片吸虫成虫制备出分泌排泄（ＥＳ）抗原，用ＳＤＳ－ＰＡＧＥ电泳，考马斯亮蓝染色显出７条蛋白带。免疫印迹试验（ＥＩＴＢ）测出其主要特异性免疫成分分子量为３６．３，２８．５及２５．５ｋＤａ，其中２８．５与２５．５ｋＤａ与法国肝片吸虫ＥＳ的部分抗原成分相同。两种片形吸虫与抗血清可以交叉使用无特异性，但与日本血吸虫抗原及抗血清均无交叉反应，人工感染大片吸虫２周后的兔血清即能识别此抗原。ＥＳ抗原提取方法简便，特异性好，敏感性高，可用于片形吸虫病免疫诊断。     

Development and characterization of a monoclonal antibody against Taura syndrome virus

We produced a panel of monoclonal antibodies (MAbs) from the fusion of Taura syndrome virus variants from Belize (TSV-BZ) immunized BALB/cJ mouse spleen cells and non-immunoglobulin secreting SP2/0 mouse myeloma cells. One antibody, 2C4, showed strong specificity and sensitivity for TSV in dot-blot immunoassay and immunohistochemistry (IHC) analysis. The MAb reacted against native TSV-BZ, TSV variants from Sinaloa, Mexico (TSV-SI) and TSV variants from Hawaii (TSV-HI) in dot-blot immunoassay. By IHC, the antibody identified the virus in a pattern similar to the digoxigenin-labelled TSV-cDNA probe for the TSV-BZ, TSV-HI and TSV-SI variants, but not for the TSV variants from Venezuela (TSV-VE) and the TSV variants from Thailand (TSV-TH). MAb 2C4 did not react against other shrimp pathogens or with normal shrimp tissue. Western blot analysis showed a strong reaction against CP2, a region of high antigenic variability amongst TSV variants. This antibody has potential diagnostic application in detection and differentiation of certain TSV biotypes.