犬细小病毒血凝抑制抗体效价胶体金免疫层析检测方法的建立及应用

试验旨在利用胶体金免疫层析技术建立快速检测犬血清中犬细小病毒（canine parvo virus, CPV）血凝抑制（haemagglutination inhibition, HI）抗体效价的方法,用于CPV疫苗免疫效果评价。采用双抗体夹心法,以抗CPV血凝相关抗原的单克隆抗体制备CPV抗原检测试纸条;将犬血清进行不同比例系列稀释后,分别与定量CPV抗原充分反应,滴入CPV胶体金试纸条,根据试纸条检测线（test line,T线）消失时的血清最高稀释倍数判断血清中CPV抗体的HI效价;用此方法检测86份犬血清样品,并与传统血凝抑制试验方法进行分析比较。结果显示,成功制备CPV抗原检测试纸条,确定了试纸条检测犬血清CPV-HI效价的反应条件和结果判定标准。结果表明,在检测不同稀释倍数犬血清反应后的CPV抗原时,能使试纸条T线消失时的血清最高稀释倍数与HI效价具有正相关性,犬血清最高稀释倍数乘以4即为HI效价;两种方法的符合率达90.7%。本试验初步建立了胶体金试纸条检测CPV血凝抑制效价的方法,为检测CPV-HI效价提供了一种操作简单、快速的试验方法,可用于CPV疫苗免疫效果评价。     

猪繁殖与呼吸综合征胶体金抗体检测技术的建立和初步应用

用胶体金标记纯化后的猪繁殖与呼吸综合征病毒(PRRSV)基因工程表达抗原,建立一种以微孔滤膜为固相载体,以红色胶体金为标记物的检测PRRSV抗体的胶体金免疫层析法(GICA).特异性交叉试验证明GICA检测PRRSV抗体有较高的特异性.与其他方法对比检测证实了其敏感性.生产了一批免疫胶体金试纸条,检测36份临床样本,其中30份经免疫胶体金试纸条及ELISA、免疫荧光检测均为阳性.猪繁殖与呼吸综合征免疫胶体金抗体检测技术的建立为检测猪繁殖与呼吸综合征病毒(PRRSV)抗体提供了一种快速简便的方法.     

犬细小病毒胶体金检测试纸条的制备与初步评价

为快速检测及诊断犬细小病毒及其引起的传染性疾病,应用胶体金免疫层析技术．采用柠檬酸三钠还原法制备25nm的胶体金颗粒,标记抗犬细小病毒单克隆抗体CPV—F1株后包被于玻璃纤维膜作为金标垫,在硝酸纤维素膜上分别包被羊抗小鼠IgG二抗和抗犬细小病毒单克隆抗体CPV—B6株作为质控线和检测线,将吸水垫、硝酸纤维素膜、金标垫和样品垫分别粘贴于背衬板上制成犬细小病毒抗原胶体金检测试纸条。特异性试验及与血凝试验的对比结果表明,该试纸条具有良好的特异性和敏感性,与进口产品的总符合率为98％。本研究为进一步研发犬细小病毒检测试纸奠定了基础。     

检测犬抗狂犬病毒抗体的胶体金免疫层析法的建立及应用

为建立一种简便快速的胶体金免疫层析方法(GICA)以用于检测犬抗狂犬病毒抗体,本研究运用间接反应一步法原理,采用柠檬酸三钠还原法制备胶体金颗粒用以标记抗犬IgG抗体形成金-抗犬IgG抗体复合物,制成金标结合垫,加上包被有狂犬病毒糖蛋白的硝酸纤维膜,即制成胶体金免疫层析试纸条.样品中狂犬病?　 毒抗体与金标记抗体结合后沿硝酸纤维素膜移动,与膜上的糖蛋白特异结合形成肉眼可见的红色线条.试验结果显示,GICA试纸条与抗狂犬病毒抗体有特异性反应,与犬瘟热病毒、犬细小病毒等的抗体无交叉反应;GICA与标准ELISA法比较的总符合率为99.4%.结果表明,GICA试纸条检测抗狂犬病毒抗体特异性强、成本低,操作简便,不需任何仪器,特别适用于野外以及现场使用.     

A群牛轮状病毒胶体金免疫层析快速诊断方法的建立与初步应用

为建立A群牛轮状病毒(BRV)快速诊断方法,采用不连续蔗糖密度梯度离心法纯化的A群牛轮状病毒为抗原,利用淋巴细胞杂交瘤技术,制备了能够稳定分泌抗BRV抗体的5株杂交瘤细胞系,将其分别命名为1D5,1B5,1G9,1C7和3C10。用直径20 nm的胶体金颗粒标记提纯的BRV单克隆抗体1G9并制备金标垫,同时将BRV高免阳性血清与羊抗鼠IgG结合于硝酸纤维素膜上,组装BRV诊断试纸条;试验结果表明,该试纸条只能检测出BRV,且检测下限可达5.3μg/mL,其他对照病毒检测结果均为阴性;表明本试验建立的A群牛轮状病毒胶体金免疫层析技术(GICA)快速诊断方法特异性强,临床应用效果好。     

Development of a Rapid Gold lmmunochromatographic Strip Test for the Diagnosis of Foot-and-Mouth Disease Virus

为了兽医基层工作人员能够快速诊断口蹄疫病原,与其他传染病做鉴别诊断,有必要建立一种快速、简便区分它们的胶体金免疫层析方法.本试验采用柠檬酸三钠还原法制备胶体金.将纯化的Asia 1/China/05流行毒株12S偶联抗原的兔抗体制备免疫胶体金,喷免疫胶体金于玻璃纤维制成金标垫.将纯化A/AF72流行株12S偶联抗原的兔抗体和适量O/China/99流行毒株12S偶联抗原的兔抗体混合固定于硝酸纤维素膜上作为检测带.将羊抗兔抗体固定在硝酸纤维素膜的不同区域作为质控带,并组装成口蹄疫病毒通用型金标检测试纸条.利用其对阴性参考样品、各型阳性参考样品、已知背景的田间样品进行检测.灵敏度试验结果显示:建立的试纸条方法敏感性高、可检测到病毒最低含量为0.98×104 LD50;特异性试验显示:在检测与口蹄疫临床症状相似病原——猪水泡病病毒(SVDV)、水泡性口炎(VS)、水泡性疹(VES)抗原时无交叉反应;重复性试验显示:不同批次间、同一批次内检测结果完全一致;符合性试验显示:检测国家口蹄疫参考实验室已确定口蹄疫病毒血清型的样品90份,阳性符合率、阴性符合率分别为96.70％、100％.本试验研发的口蹄疫病毒通用型金标检测试纸条具有很好的灵敏度、特异性、重复性和符合性,适合国内流行的口蹄疫病原的鉴别诊断.     

犬病快速检测试纸条

犬病快速检测试纸条是采用胶体金标记免疫层析技术制成的，是一种快速检测犬体内特定抗原（抗体）的试纸。目前可检测犬传染病数十种，此试纸条具有快速、简便、实用等优点，现已被广泛应用在犬病的临床诊断中，同时它也作为犬饲养者家中自测犬病的首选工具。本文以犬瘟热病毒抗原检测试纸条举例说明。     

快速检测猪繁殖与呼吸综合征病毒胶体金免疫层析方法的建立

为建立一种快速、简便、灵敏的检测猪繁殖与呼吸综合征病毒(PRRSV)的胶体金免疫层析方法(GICA),本研究采用柠檬酸三钠还原法制备了胶体金颗粒,标记抗PRRSVN蛋白的单克隆抗体(MAb) 2D7制备免疫检测探针,将抗PRRSVN蛋白的MAb 1G7和羊抗鼠IgG抗体印迹在硝酸纤维素膜上,分别作为检测线和质控线,经条件优化,组装成胶体金免疫层析试纸条.本研究制备的PRRSV胶体金试纸条的最低检测限度为103.0 TCID50/mL;在特异性试验中,试纸条检测PRRSV呈阳性,其它主要猪病病原均为阴性;不同批次试纸条重复检测,结果无差异;对现地猪场送检的150份病料进行PRRSV病原检测,与RT-PCR相比较,试纸条的特异性和敏感性分别为98.13％和88.37％.两种方法的一致性Kappa值为0.882.建立的PRRSV抗原胶体金免疫层析检测方法具有良好的的敏感性、特异性、重复性及现地应用性.该试纸条的研制为PRRS的快速诊断及免疫预防提供了技术手段.     

犬病快速检测试纸条

犬病快速检测试纸条是采用胶体金标记免疫层析技术制成的,是一种快速检测犬体内特定抗原(抗体)的试纸。目前可检测犬传染病数十种,此试纸条具有快速、简便、实用等优点,现已被广泛应用在犬病的临床诊断中,同时它也作为犬饲养者家中自测犬病的首选工具。本文以犬瘟热病毒抗原检测试纸条举例说明。检测方法:用生理盐水沾湿的棉签收集病犬的眼     

牛结核病抗体胶体金快速检测技术的建立和应用

为了建立一种快速检测牛分支杆菌抗体的新方法用于诊断牛结核病,利用胶体金免疫层析技术原理,用原核诱导表达的牛分支杆菌抗原蛋白MPB83和MPB70分别作为胶体金标记抗原和检测线上的捕获抗原,制备牛结核抗体检测试纸条.结果表明,粒径为40 nm的胶体金制备的试纸条敏感性最高,胶体金最佳标记pH为6.0,MPB83抗原最适标记量为每毫升胶体金6.5 μg,MPB70抗原的最适包被浓度为3.0 mg/mL,抗MPB83蛋白IgG的最佳包被浓度为2.5 mg/mL,交叉试验证明试纸条不与牛的其他非相关疾病的阳性血清反应,具有较高的特异性.比较试验证明其敏感性显著高于韩国进口试纸条.在上述试验条件下生产了一批胶体金试纸条进行临床样品检测,并与细菌分离培养、结核菌素皮内变态反应(TST)和韩国试纸条比较.本试纸条与牛分支杆菌分离培养的符合率为85%,与TST的符合率为79.73%,与韩国试纸条的符合率为98.75%.快速检测牛结核抗体的免疫层析试纸条具有敏感、特异、简便、快速的特点,适用于对牛结核病进行普查和检疫,也可作为TST的辅助诊断方法,在牛结核病根除计划中具有良好的应用前景.     

Establishment and Application of Colloidal Gold Immune Chromatography Test Method for Detection of Canine Parvovirus Hemagglutination Inhibition Antibody Titer

The study was aimed to use colloidal gold immune chromatography technology to establish a rapid method for detection of canine serum canine parvovirus (CPV) hemagglutination inhibition (HI) titer and CPV vaccine immunization effect assessment.Double antibody sandwich method and monoclonal antibodies of anti-CPV hemagglutination antigen were used to prepare CPV antigen test strip.Canine serum with different proportion respectively was mixed with quantitative CPV antigen for full reaction,then dropped the mixture into the CPV colloidal gold test strip,so according to the highest serum dilution ratios when the test strip line T (line T) vanishes,it was to judge CPV antibodies in serum of the HI titer.This method had been used to detect 86 canine serum samples,at the same time,analyzing and comparing it with traditional hemagglutination inhibition test method.The results showed that the CPV antigen detection test strip was successfully prepared,and the reaction conditions and results of the test strip for detecting the titer of CPV-HI in canine serum were determined.The results indicated that when detecting CPV antigen after the dilution of different ratios of canine serum,the highest serum dilution ratios when the strip line T vanished and the HI titer had positive correlation.The highest dilution ratios of canine serum multiplied by 4 was the HI titer.The results of two methods had 90.7% consistency.This experiment established the colloidal gold immune chromatography test strip for the detection of CPV-HI titers method initially.This CPV-HI detection provided a simple and fast test method for the effect evaluation of CPV vaccine immune.     

Hemagglutination by canine parvovirus: serologic studies and diagnostic applications

Conditions for canine parvoviral hemagglutination (HA) and hemagglutination-inhibition (HI) reactions were defined. The HA phenomena were used to differentiate canine parvovirus (CPV) from feline panleukopenia virus (FPV), mink enteritis virus (MEV), and minute virus of canines. Serologic comparisons of the CPV, FPV, and MEV by HA-HI and serum-neutralization tests indicated that CPV, FPV, and MEV were antigenically similar but were different from minute virus of canines. Diagnostic application of HA tests to fecal samples from acute cases of enteritis was discussed. Combinating HA tests with HI tests on fecal samples provided a rapid and specific diagnostic method for CPV infection. Secular seroprevalence studies indicated the emergence of CPV infeciton in the United States dog population-at-large in 1978.     

Application of a dot enzyme-linked immunosorbent assay for evaluation of the immune status to canine parvovirus and distemper virus in adult dogs before revaccination.

A growing body of literature has been published indicating that the current practice of annual vaccination of dogs may not be beneficial and in some cases may even be harmful. A number of publications have proposed assessing the immune status of dogs before annual revaccination. In this study the usefulness of a commercially available dot-ELISA kit was evaluated to determine the duration IgG antibody titers to canine parvovirus (CPV) and canine distemper virus (CDV) in 158 dogs vaccinated at least one year ago. Overall, the percentage of dogs with protective antibody titers to both CPV and CDV was 84%. The percentage of dogs with borderline antibody titers was 11% for CPV and 10% for CDV. Four percent of the dogs had no detectable antibody to CPV and 6% had no antibody to CDV. The results reported here are in good agreement with other studies measuring IgG antibody levels. It is concluded that the kit offers veterinarians the opportunity of determining antibody titers and revaccinating only those pets whose antibody titers to specific diseases have waned.     

Accuracy of a point-of-care ELISA test kit for predicting the presence of protective canine parvovirus and canine distemper virus antibody concentrations in dogs

Canine parvovirus (CPV) and canine distemper virus (CDV) are highly infectious and often fatal diseases with worldwide distributions, and are important population management considerations in animal shelters. A point-of-care ELISA test kit is available to detect serum antibodies to CPV and CDV, and presumptively to predict protective status. The aim of this study was to determine the diagnostic accuracy of the test compared to CPV hemagglutination inhibition titers and CDV serum neutralization titers determined by a reference laboratory, using sera collected from dogs housed at animal shelters. The ELISA test was used under both field and laboratory conditions and duplicate specimens were processed using an extra wash step. The test kit yielded accurate results (CPV: sensitivity 92.3%, specificity 93.5%; CDV: sensitivity 75.7%, specificity 91.8%) under field conditions. CDV sensitivity was improved by performing the test under laboratory conditions and using an optical density (OD) meter (laboratory performed 94.0%; OD 88.1%). Point-of-care ELISA testing for serum CPV and CDV antibody titers was demonstrated to be a useful tool for determining antibody status when making decisions regarding the need for CPV and/or CDV vaccination and also in animal shelters for population management.     

犬瘟热病毒单克隆抗体的研制及胶体金试纸条检测方法的建立

本研究利用原核表达、纯化的犬瘟热病毒(Canine distemper virus,CDV)N 蛋白免疫BALB/C小鼠,成功筛选到两株分泌CDV N 蛋白单克隆抗体的杂交瘤细胞株,分别命名为D3、D6。2株杂交瘤细胞分泌单克隆抗体敏感性、特异性良好,能识别不同来源的犬瘟热病毒株,单抗亚类均为IgG1。以D3作为金标抗体,D6作为检测抗体,兔抗鼠IgG作为质控线抗体,制备犬瘟热病毒胶体金检测试纸条,检测犬瘟热病毒敏感性为1000TCID50,能有效检测区分犬瘟热病毒、犬细小病毒(Canine parvovirus,CPV)、犬腺病毒2型(Canine adenovirus type 2,CAV2)、狂犬病病毒(Rabies virus,RV)。综上,本研究建立的胶体金试纸条检测方法,灵敏度高、特异性强,适用于犬瘟热病毒临床快速诊断。     

Canine parvovirus type 2c identified from an outbreak of severe gastroenteritis in a litter in Sweden

A litter of recently-vaccinated puppies in Sweden experienced signs of severe haemorrhagic gastroenteritis. Canine parvovirus (CPV) was suspected as the cause of this outbreak on the basis of the clinical signs and the presence of parvoviral antigen in the faeces from one of the affected pups - confirmed using a commercial in-clinic faecal antigen ELISA test kit. A concern was raised about whether the vaccine (which contained a live, attenuated strain of CPV) could have caused the disease and so further faecal samples from the affected pups were submitted for laboratory virus isolation and identification.On cell culture, two out of four faecal samples were found to be virus-positive. This was confirmed as being canine parvovirus by immuno-staining with CPV specific monoclonal antibody. The virus was then tested using a series of PCR probes designed to confirm the identity of CPV and to distinguish the unique vaccine strain from field virus. This confirmed that the virus was indeed CPV but that it was not vaccine strain. The virus was then typed by sequencing the 426 amino acid region of the capsid gene which revealed this to be a type 2c virus.Since its emergence in the late 1970s, canine parvovirus 2 (CPV2) has spread worldwide and is recognised as an important canine pathogen in all countries. The original CPV2 rapidly evolved into two antigenic variants, CPV2a and CPV2b, which progressively replaced the original CPV2. More recently a new antigenic variant, CPV2c, has appeared. To date this variant has been identified in many countries worldwide but there have been no reports yet of its presence in any Scandinavian countries. This case report therefore represents the first published evidence of the involvement of CPV2c in a severe outbreak of typical haemorrhagic gastroenteritis in a susceptible litter of pups in Scandinavia.     

Evaluation of enzyme-linked immunosorbent assays based on monoclonal antibodies for the serology and antigen detection in canine parvovirus infections

An enzyme-linked immunosorbent assay (ELISA) system was developed for the detection of canine parvovirus (CPV) or CPV antigen in dog faeces and two other ELISA systems were developed for the detection of CPV-specific antibodies in dog sera. The ELISA's were based on the use of CPV-specific mouse monoclonal antibodies, which recognise different epitopes of the haemagglutinin of CPV and which also neutralise the virus. A double antibody sandwich (DAS) ELISA for the detection of CPV in dog faeces was compared with the haemagglutination (HA) test. The DAS-ELISA proved to be more specific, sensitive and easier to perform than the HA assay. An indirect ELISA and a competitive ELISA for the detection of CPV-specific antibodies in dog sera were compared with the haemagglutination inhibition (HI) test. Both ELISA systems proved to be specific and easy-to-use methods for the detection of CPV-specific antibodies. The indirect ELISA, specially, proved to be more sensitive than the HI test. The higher sensitivity and specificity of the ELISA's as compared to HA and HI tests, and their ease of use, make them suitable for routine use in the serology and diagnosis of CPV infections.     

犬细小病毒特异性免疫球蛋白的临床应用效果观察

旨在观察犬细小病毒特异性免疫球蛋白治疗犬细小病毒病的临床应用效果,本文收集了中国农业大学动物医院自2016年1月—2019年11月接治的犬细小病毒病患犬的病历资料,筛选出病历资料完整的并使用了犬细小病毒单抗或犬细小病毒特异性免疫球蛋白治疗的患犬病例进行跟踪以及回访。对收集的病例数据进行了总治愈率、各初始抗体水平的治愈率、各月龄段的治愈率和治愈病例的病程分析。结果显示,犬细小病毒特异性免疫球蛋白和犬细小病毒单克隆抗体在总治愈率、相同初始抗体水平治愈率、相同月龄段治愈率均无显著差异（P>0.05）。但使用特异性免疫球蛋白的病例痊愈时间显著低于使用单克隆抗体的病例（P=0.02<0.05）。综上表明,犬细小病毒特异性免疫球蛋白的临床应用效果良好,可为犬细小病毒病的治疗提供新的药物选择。     

犬细小病毒HZ0761株的分离与鉴定

采集疑似细小病毒(CPV)感染犬的粪便,采用同步培养法接种胎猫肾细胞(F81)进行病毒分离鉴定。通过PCR检测、HA试验、IFA鉴定、电镜观察和空斑纯化,获得1株犬细小病毒,并命名为HZ0761。感染的F81细胞48h后出现明显的细胞病变;在病料和感染的F81细胞中均扩增出CPV VP2基因的特异性片段(221 bp);病毒液可凝集猪红细胞,血凝价为1∶28,其血凝性能被特异性抗体抑制;IFA可见特异性亮绿色荧光;电镜观察感染的F81细胞核内可见20 nm左右的病毒颗粒;病毒液的TCID50为10-4.8/mL,VP2基因序列分析显示该毒株为CPV-2 a型。