猪支原体重组MSG1蛋白间接ELISA检测方法的建立

为确定猪支原体在临床的感染情况和进行血清流行病学调查,本研究以原核表达纯化的猪支原体MSG1重组蛋白为包被抗原,建立了检测猪支原体的间接ELISA诊断方法。通过对ELISA反应一系列条件的优化,确定了最佳抗原包被浓度为0.5μg/mL;最佳封闭条件为用1%BSA37℃温箱内封闭2 h;血清最适稀释度为1∶200,作用时间为1.5 h;酶标二抗最适稀释度为1∶15 000,最适作用时间为1 h;最后37℃显色15 m in。判定标准为OD450≥0.239时判为阳性,OD450<0.198时判为阴性,0.198≤OD450<0.239时判为可疑。敏感性、特异性和可重复性试验证明,该检测方法敏感性高、特异性强和可重复性好。该研究表明建立的间接ELISA方法为猪支原体的检测和区域流行病学调查提供了一种快速简便的血清学诊断方法。     

抗猪(嗜血)支原体MSG1蛋白单克隆抗体的制备及鉴定

以原核表达纯化的猪(嗜血)支原体MSG1蛋白免疫BALB/c小鼠,运用细胞融合技术筛选分泌针对MSG1蛋白抗体的融合细胞。通过间接ELISA方法筛选获得2株能稳定分泌抗体的融合细胞株,分别命名为1A7和3G6,Western blot结果证明这2株细胞分泌的抗体能够与重组MSG1蛋白发生特异性反应。细胞上清和腹水中的ELISA抗体效价分别为1∶4 096、1∶1 024和1∶1 638 400、1∶51 200,其单抗亚类鉴定均属于IgG1,轻链为κ型。抗原识别位点分析结果表明,2株单抗所识别的抗原位点相同。猪(嗜血)支原体MSG1蛋白特异性单克隆抗体的制备成功,为制备免疫诊断试剂盒和致病机制的研究奠定了基础。     

抗猪肺炎支原体IgA间接ELISA检测方法的建立

为了更准确地对猪肺炎支原体感染及免疫状况进行检测,作者拟建立抗猪肺炎支原体IgA间接ELISA检测方法.在比较了猪肺炎支原体全菌抗原和粘附因子P97R1原核表达蛋白后,选择后者作为包被抗原;以羊抗猪IgA为二抗,兔抗猪IgG-HRP作为酶标三抗,并分别对包被抗原的浓度、样品的孵育时间、二抗与三抗的最佳稀释度和作用时间以及显色液的作用时间作了优化.最终建立了稳定而特异的抗猪肺炎支原体IgA的间接ELISA检测方法.批间与批内试验结果证明该方法具有很好的稳定性.初步应用表明,该方法可用于猪肺炎支原体感染或免疫状态的临床监测.     

副猪嗜血杆菌间接ELISA抗体检测方法的建立

采用福尔马林灭活的副猪嗜血杆菌全菌体作为包被抗原,建立了检测副猪嗜血杆菌抗体的间接ELISA方法。经试验确定副猪嗜血杆菌全菌体的包被浓度为2·24×107CFU/孔、检测血清为1∶200稀释,同时确立了间接ELISA的最佳反应条件。该方法有很高的特异性和重复性,14个发病猪场100份血清检测结果Hps抗体阳性检出率为94%,明显高于细菌分离鉴定检测结果。     

酶标单抗阻断ELISA检测鸡白痢和鸡伤寒抗体

以辣根过氧化物酶标记的沙门氏菌O9单抗3-47-0与包被的鸡白痢沙门氏菌脂多糖抗原建立了一种抗体阻断EL ISA以检测鸡白痢和鸡伤寒沙门氏菌感染。该方法基于待检血清样品抑制酶标单抗与脂多糖的结合,以检测鸡白痢和鸡伤寒特异性抗体。对72份已知鸡白痢阳性血清(抑制率为(98.5±4.0)%)、54份已知鸡白痢阴性血清(抑制率为(15.3±8.0)%)、42份SPF鸡血清(抑制率为(0.8±7.2)%)检测的结果表明,该方法具有很强的区分能力。在人工感染试验中,从第2周开始,该方法能从全部鸡只中检测到特异性抗体,比全血玻板凝集试验(PAT)早1周时间。对344份种鸡血清的检测结果表明,单抗阻断EL ISA比PAT特异性好、敏感性高。另外,该方法也能检测出与鸡白痢和鸡伤寒沙门氏菌有共同抗原的沙门氏菌感染产生的抗体。     

猪嗜血支原体病研究进展

猪嗜血支原体可引起猪传染性贫血或猪嗜血支原体病,该病原体在世界范围内分布范围广,严重阻碍养猪业的发展。笔者等从猪嗜血支原体病的病原学、致病机理、临床症状、诊断及防制等方面进行综述,拟为该病的研究提供参考。     

猪流行性腹泻病毒N蛋白阻断ELISA抗体检测方法的建立及初步应用

旨在建立一种猪流行性腹泻病毒(PEDV)N蛋白阻断ELISA抗体检测方法.本研究将纯化的N蛋白作为包被抗原,通过棋盘滴定法优化ELISA反应条件,建立了检测PEDV抗体的阻断ELISA方法,并对其进行特异性、敏感性和重复性试验.对140份临床血清样品进行检测,并将检测结果与市售IDvet PEDV间接ELISA抗体检测...     

猪嗜血支原体PCR及荧光定量PCR检测方法的建立和比较

为了解猪嗜血支原体(Mycoplasma haemosuis)对猪群的感染情况并建立该病的检测方法,本研究根据GenBank登录的M.haemosuis 16S rRNA基因序列(FJ263944)设计合成PCR引物以及荧光定量PCR(FQ-PCR)引物和探针.以含16S rRNA基因的重组质粒为模板,通过对PCR反应...     

猪肺炎支原体融合蛋白MHP-P46-P36的表达及间接ELISA抗体检测方法的建立

利用生物学软件分析猪肺炎支原体P46蛋白和P36蛋白的抗原决定簇,将抗原表位富集区进行串联,表达融合蛋白MHP-P46-P36。以融合蛋白MHP-P46-P36作为包被抗原,优化反应条件建立肺炎支原体间接ELISA抗体检测方法。结果显示：融合蛋白MHP-P46-P36以可溶性形式高效表达;ELISA检测方法的最适抗原包被质量浓度10 mg/L, 1%BSA封闭60 min,一抗最佳稀释度1∶40且37℃60 min,二抗最佳稀释度1∶4 000且37℃60 min,最适显色时长15 min, cut-off值为D_{450 nm}=0.385;与猪瘟病毒、猪伪狂犬病病毒、猪鼻支原体、猪絮状支原体、猪蓝耳病病毒和猪圆环病毒阳性血清无交叉反应,具有良好的特异性;阴阳性血清的组内和组间变异系数均小于7%,具有较好重复性;52个样品临床样本检测结果显示,建立的ELISA方法与IDEXX猪肺炎支原体抗体检测试剂盒相比,阳性样本的符合率为83.09%。     

抗猪嗜血支原体中药单体的体外筛选

为体外筛选具有杀灭猪嗜血支原体(M.suis)作用的中药单体,应用血液直接PCR扩增中药单体作用不同时间后培养体系中的M.suis,通过比较电泳条带灰度值筛选出具有抗M.suis作用的中药单体;应用qPCR测定所筛选中药单体作用后培养体系中M.suis的拷贝数,通过杀灭率来评估中药单体对M.suis的杀灭效果。结果筛选出丹参酮ⅡA磺酸钠、甘草酸二钾、秦皮甲素、黄芩苷和肉桂酸5种具有体外抗M.suis作用的中药单体,其中在药物作用18h,丹参酮ⅡA磺酸钠、甘草酸二钾和秦皮甲素对M.suis杀灭率分别为76.9%,90.6%和79.2%。体外试验表明,丹参酮ⅡA磺酸钠、甘草酸二钾和秦皮甲素对M.suis的杀灭效果较好,是理想的抗M.suis目标药物,具有潜在的临床应用与研究价值。     

抗猪肺炎支原体特异性P36蛋白单克隆抗体的制备与鉴定

表达P36基因的重组菌BL21(6P-1-P36)经诱导表达,超声波裂解后高速离心,分别收集上清和沉淀。可溶性表达产物亲和层析纯化后用于单抗筛选;同时,用GST-P36包涵体抗原腹腔注射免疫BALB/c小鼠(400μg/只)。利用淋巴细胞杂交瘤技术,获得了1株能分泌特异性抗体的杂交瘤细胞株5A7-2。生物学特性鉴定表明,腹水单抗的间接ELISA效价为1∶2.5×106;免疫球蛋白亚类为IgG2a。免疫印迹结果显示,腹水单抗能与GST-P36融合蛋白反应而不与谷胱苷肽转移酶(GST)反应,并且在猪肺炎支原体(Mycop lasma hyopneumoniae,Mhp)蛋白36000位置也有明显的条带,说明5A7-2所分泌的是针对MhpP36蛋白的单抗。P36蛋白是Mhp种特异性蛋白,其单克隆抗体的制备,为Mhp种特异性检测方法的建立奠定了基础。     

非洲猪瘟病毒p30蛋白单克隆抗体的制备及阻断ELISA抗体检测方法的建立

为建立检测非洲猪瘟病毒(ASFV)抗体的阻断ELISA方法,本研究利用原核表达的ASFV p30重组蛋白免疫BALB/c小鼠制备单克隆抗体。以重组p30蛋白作为包被抗原,以辣根过氧化物酶(HRP)标记的p30单克隆抗体作为检测抗体,经条件优化,建立了一种检测ASFV抗体的阻断ELISA方法。ROC曲线分析显示,该方法最佳阻断率临界值为16.63%。该方法与CSFV、FMDV-O/A、PRRSV、PEDV、SVA的阳性血清均无交叉反应;最低能检出1∶128稀释的阳性血清;批内和批间变异系数(CV)均＜10%。用本方法与商品化试剂盒平行检测208份血清样品,Kappa值为0.96,表明具有高度一致性。上述结果表明,本研究建立的阻断ELISA方法具有较高的特异性和敏感性,可用于血清ASFV抗体的检测,为ASFV流行病学调查及猪群疫情监控提供技术支持。     

Development of a Neutralizing Monoclonal Antibody-based Blocking ELISA for Detection of Equine Herpesvirus 1 Antibodies

A single-dilution, sensitive and specific monoclonal antibody-based blocking enzyme-linked immunosorbent assay (B-ELISA) was developed as an alternative to the cumbersome virus neutralization test (VNT) for detection of equine herpesvirus-1 (EHV-1) antibodies. Neutralizing monoclonal antibodies (1H6 and 9C6) raised against EHV-1 (Hisar-90-7 strain) and sera from 70 horses (30 known negative and 40 known positive for EHV-1 antibodies by VNT) were used for standardization of the B-ELISA. Using a single serum dilution of 1:250 in B-ELISA, 100% specificity was obtained with both monoclonal antibodies (Mabs) in comparison to VNT. Similarly, the sensitivity of the B-ELISA was 92.5% and 100% with 1H6 and 9C6 Mabs, respectively. A very high correlation coefficient (r = 0.85) was observed between B-ELISA and VNT that was significant at the p < 0.01 level. B-ELISA detected a more than 3-fold rise in antibody titres in paired serum samples collected from mares aborting owing to EHV-1 infection. Mab 9C6 was chosen for testing 231 field sera from apparently healthy vaccinated and non-vaccinated horses from organized breeding farms belonging to 11 Indian states, and from Bhutan, by B-ELISA and VNT. There was very good agreement between the results obtained by both VNT and B-ELISA (K = 0.9438). Of 231 field sera, 144 samples were negative for EHV- 1 antibodies by both VNT and B-ELISA and 81 were positive by both tests. Two samples negative by VNT were found positive in B-ELISA. On the other hand, four weakly positive samples in VNT (VN antibody titre 0.9 1.2 log10) were negative in B-ELISA. The Mab (9C6)-based B-ELISA was found to be a suitable alternative to VNT for screening large numbers of field sera and enabled confirmatory EHV-1 serodiagnosis.     

Preparation of Cathepsin L1 Monoclonal Antibody Against Fasclala gigantica and Establishment of Double Antibody Sandwich ELISA

【Objective】 This study was intend to obtain cathepsin L1(rFgCat L1) specific monoclonal antibody and construct the double antibody sandwich ELISA.【Method】 Five BALB/c mice were immunized with 1 mg/mL rFgCat L1 protein for four times.Mouse splenocytes were isolated and fused with SP2/0 cells to construct hybridoma cells.Strong positive hybridoma cell lines were screened, 1×10⁶ cells were injected intraperitoneally per mouse to prepare monoclonal antibodies.Antibody titer and antigenic epitope were detected using ELISA method, antibody subtype and specificity were identified using Western blotting method.The double antibody sandwich ELISA was constructed by combining the anti-rFgCat L1 polyclonal antibody, and its sensitivity and specificity were tested.The positive and negative critical value was screened by 20 negative sera with positive control, and the constructed double antibody sandwich ELISA was verified by 47 goat positive sera and 47 dairy cow positive sera.【Result】 After immunization, the antibody titers in serum of 4 mice were all more than 10⁴.After isolated mouse with the highest immune response spleen cells were fused with SP2/0 cells total of 8 of them were positive cell lines were obtained after selective culture.5D5 and 7G6 were identified as strong positive strains with stable antibody secretion.After multiple subcloning screens and subcultures, the antibodies secreted in the cell supernatant were stable, with titers of 2⁹ and 2¹⁰ respectively, with ascites titers of 10⁷ and 10⁸.Western blotting and antibody subtype identification kits identified that the two antibodies were IgG1 type and the light chain was kappa type, both of which could specifically bind FgESP.According to the same antigen site was recognized by the two kinds of antibodies, the antigen titer of the two monoclonal antibodies were comparied, 7G6 was used as the coating antibody, and anti-rFgCat L1 was used as the enzyme-labeled secondary antibody.The optimized condition of method was that 7G6 was coated at a concentration of 2 μg/mL, the dilution concentration of anti-rFgCat L1 polyclonal antibody was 25 μg/mL, the dilution of Don-HRP-conjugated was 1∶4 000, 5% skimmed milk powder was selected as the blocking solution and the color development time was 25 min.The method was proved that could recognize the lowest antigen concentration of 0.625 μg/mL, also could specifically recognize antigen of Fasciola fasciatus.The constructed sandwich ELISA method was used for antigen detection of 47 dairy cow positive serum and 47 goat positive serum infective samples kept in the laboratory and the positive antigen rate were 72.3% and 78.7%, respectively.【Conclusion】 Anti-rFgCat L1 monoclonal antibody was successfully prepared and the double-sheet sandwich ELISA method for fascioliasis was constructed, which provided a good theoretical basis and material basis for the development of low-cost and rapid diagnostic kits.     

新霉素阻断ELISA试剂盒的研制与应用

本研究旨在建立新霉素(Neomycin,NEO)免疫学检测试剂盒.以制备的抗NEO单克隆抗体(NEO mAb)为基础,建立阻断ELISA分析方法,组装新霉素阻断ELISA试剂盒,并对试剂盒的性能进行鉴定.结果表明,NEO试剂盒(NEO-kit)标准曲线呈典型的S型,符合4参数logit曲线拟合,相关系数R2=0.990 3;检测范围为1.0～64.0μg·L-1,半数抑制浓度(IC50)为2.59 μg·L-1,灵敏度为0.75 μg·L-1,检测限为1.0 μg·L1.试剂盒除了和NEO阳性样品反应呈阳性外,与庆大霉素、链霉素、土霉素、沙丁胺醇、环丙沙星、二氟沙星、磺胺嘧啶及磺胺甲噁唑等其他药物均无交叉反应性.奶样、饲料样及肉样的平均添加回收率为89.50%、89.58%和87.92%;平均批内和批间变异系数均小于15%,而且批间变异系数小于批内变异系数;基质对NEO-Kit的检测结果影响比较小;NEO-Kit在4℃可保存6个月以上.试剂盒和HPLC-MS-MS对牛奶中新霉素回收率没有显著差异(P≥0.05).试剂盒和HPLC-MS-MS对饲料样检测结果也无显著差异(P≥0.05).本研究成功研制出敏感、特异、准确的NEO检测试剂盒.     

非洲猪瘟病毒p72蛋白阻断ELISA检测方法的建立

本研究旨在建立一种非洲猪瘟病毒(ASFV)p72蛋白阻断ELISA抗体检测方法。以纯化的重组p72蛋白作为包被抗原,HRP标记的6E5抗体作为阻断抗体,通过对反应条件进行优化,建立了基于ASFV p72蛋白的阻断ELISA方法。用建立的阻断ELISA方法检测119份临床阴性血清,计算血清阻断率确定临界值,确定了该方法的判定标准：当阻断率PI≥50%时判定为ASFV抗体阳性;PI≤40%时判定为ASFV抗体阴性;当阻断率介于两者之间时,判定为可疑。该方法与猪伪狂犬病病毒、猪繁殖与呼吸综合征病毒、猪瘟病毒、猪圆环病毒2型、A型塞内卡病毒、猪口蹄疫病毒、猪大肠杆菌、猪多杀性巴氏杆菌、副猪格拉瑟菌和猪胸膜肺炎放线杆菌的抗体阳性血清无交叉反应,批间、批内试验的变异系数均小于15%。用该方法与商品化ASFV抗体检测试剂盒同时检测447份猪临床血清样品,两种方法的相对敏感性和相对特异性分别为95.3%和94.5%,符合率为94.9%。本研究建立的阻断ELISA方法具有较高的敏感性和良好的特异性,可用于ASFV感染诊断和流行病学调查。     

非洲猪瘟病毒p54蛋白单克隆抗体的制备及阻断ELISA方法的建立

旨在建立检测非洲猪瘟病毒(ASFV)血清抗体的阻断ELISA方法.采用原核表达的ASFVp54蛋白作为包被抗原,并制备了针对p54蛋白的单克隆抗体,采用方阵滴定法确定了阻断ELISA方法的最佳反应条件,并对建立的方法进行了敏感性、特异性、重复性和符合性评价.结果显示,抗原最佳包被浓度为2.0 μg·mL-1,抗原包被温...