马疱疹病毒1型感染马疾病模型的建立及评价

试验旨在建立马疱疹病毒1型（Equine herpesvirus type1,EHV-1）人工发病模型,确定EHV-1感染马的半数感染量（ID₅₀）及感染发病的判定标准,为该病的预防与治疗药物的研发奠定基础。以新疆伊犁地区某发病马场流产胎儿中分离的EHV-1 XJ2015株为研究对象,设立4组不同病毒剂量感染组及对照组,经鼻内喷雾感染马,5 mL/匹,每天观察试验马的临床症状和发病情况,14 d后进行剖检,观察各组织脏器病理变化并应用实时荧光定量PCR方法检测鼻腔排毒及病毒分布情况。结果显示,EHV-1 XJ2015株感染马的ID₅₀为10^-6.67/5 mL,其病毒含量为10^4.33 TCID₅₀/mL。与对照组相比,1×10⁶和1×10⁵ TCID₅₀/mL感染组马临床评分显著升高,主要表现为体温升高（高达39.5 ℃,一般持续2~6 d）、食欲不振、流浆液性鼻液和下颌淋巴结肿大;且1×10⁶和1×10⁵ TCID₅₀/mL感染组试验马均表现出不同程度的排毒,肺脏及脑组织中可检测出大量病毒,与对照组相比极显著或显著升高（P<0.01;P<0.05）;病理学检查发现,患马脑组织出现非化脓性脑炎及神经元水肿,肺脏组织出现间质性肺炎、嗜中性粒细胞、炎性细胞浸润、出血和肺泡间隔增厚。以上结果表明,EHV-1 XJ2015株对马具有较强的致病性,患病马临床症状典型,病毒主要随鼻液排出,并富集在肺脏及脑组织,通过上述指标确定EHV-1感染马发病的判定标准,本试验成功建立EHV-1感染本体动物疾病模型。     

含EGFP基因的马疱疹病毒1型新疆株gE基因缺失株的构建

为筛选马鼻肺炎（equine rhinopneumonitis,ER）基因缺失减毒活疫苗的候选毒株,本研究参考GenBank中EHV-1（登录号：KF644579.1）目的基因序列设计同源臂引物,以本地区流行株XJ2015株DNA为模板PCR扩增gE基因同源臂gEH1、gEH1,以EGFP表达盒（CMV+EGFP+polyA）为标记基因,酶切后依次连接至载体pUC-19,成功构建重组质粒pUC-gEH1H2-EGFP。将XJ2015基因组与质粒pUC-gEH1H2-EGFP共转染至RK-13细胞进行同源重组,以EGFP为标记进行gE基因缺失毒株的筛选及纯化,并测定重组毒株效价。结果显示：经5轮荧光噬斑纯化、PCR及测序鉴定,成功获取一株携带EGFP基因的重组毒株XJ2015-△gE-EGFP,且重组毒株效价（10^7.1TCID₅₀/0.1 mL）较原毒株（10^8.8TCID₅₀/0.1 mL）下降约10^1.7TCID₅₀/0.1 mL。采用同源重组技术成功构建了1株马疱疹病毒1型流行株gE基因缺失突变株,为未来筛选马鼻肺炎基因缺失弱毒疫苗奠定了基础。     

马疱疹病毒1型主要毒力基因分析及TK基因缺失载体的构建

为了解新疆马疱疹病毒1型（EHV-1）主要毒力基因遗传进化情况并构建TK基因缺失株,本研究以EHV-1 XJ2015株DNA为模板,对其主要毒力基因TK、gI和gE全长进行克隆、测序及生物信息学分析,并扩增TK基因左右重组臂TKL和TKR,构建质粒pUC-TKLR,将扩增后的增强绿色荧光蛋白（EGFP,含有CMV+polyA）插入pUC-TKLR质粒,构建TK基因缺失打靶质粒。TK、gI和gE基因同源性分析结果显示,XJ2015株与国外EHV-1分离株TK、gI和gE基因同源性均较高,分别为99.8%~100.0%、99.6%~100.0%和99.9%~100.0%;与EHV-3分离株同源性均最低,分别为72.9%、59.4%和62.1%;遗传进化分析显示,3个基因均与国外EHV-1同属于一个遗传进化分支,与EHV-9和EHV-4进化关系较近,但与EHV-3进化关系较远,表明XJ2015毒株与国外EHV-1毒株TK、gI、gE基因核苷酸上差异不明显,没有明显的地域性特征,功能基因保守且进化缓慢,同源基因功能相同或相近;经PCR扩增、酶切、测序及转染鉴定,本试验成功构建了用于TK基因缺失的打靶质粒pUC-TKLR-EGFP。通过对EHV-1主要毒力基因的分析及TK基因缺失打靶载体的构建,为新疆地区马鼻肺炎流行病学调查分析、TK基因缺失株的构建提供理论依据。     

马疱疹病毒1型LAMP检测方法的建立

本试验旨在建立一种检测马疱疹病毒1型（EHV-1）的快速、灵敏、特异的环介导等温扩增技术（LAMP）,同时评价该方法的可靠性。根据马鼻肺炎糖蛋白B（gB）基因特异保守序列设计多对LAMP引物,利用LAMP Real Time Turbidimeter LA-320仪监测反应进程,进行引物筛选和反应条件的优化,建立能特异性扩增EHV-1 DNA的LAMP检测方法,并加入SYBR GreenⅠ通过肉眼判断结果。该方法在65 ℃恒温下作用50 min,使EHV-1 DNA获得了高效率的特异性扩增,与其他马易感病毒如马疱疹病毒4型（EHV-4）等无交叉反应;且具有极高的灵敏性,可检测到10^-4稀释的目标病毒,比普通PCR的灵敏度高10倍;反应结束后加入SYBR GreenⅠ肉眼观察的结果与LAMP Real Time Turbidimeter LA-320仪监测结果一致。通过将4份临床样品的LAMP检测结果与已得到验证的PCR结果进行比对,结果显示符合率为100%。本研究建立的LAMP检测方法具有快速、特异、灵敏、简单易操作且设备要求低等特点,具有实地检测EHV-1的前景。     

鸭疱疹病毒1型套式PCR检测方法的建立及应用

为建立一种快速鸭疱疹病毒1型(Anatid herpesvirus 1,AHV-1),又名鸭肠炎病毒(duck enteritis virus,DEV)病原检测方法,本研究根据GenBank上登录的DEV基因序列,设计合成内、外2对引物,建立了检测DEV的套式PCR方法。该方法对正常鸭胚、健康鸭肝肠组织、鸡传染性喉气管炎病毒、伪狂犬病病毒、减蛋综合征病毒、鸭肝炎病毒和新城疫病毒的扩增结果均为阴性;该方法第1次扩增的敏感性是10 ng,第2次扩增的敏感性是0.1 ng,第2次比第1次扩增的敏感性高100倍。建立的套式PCR方法具有良好的特异性、敏感性,可以准确快速检测出极低含量的DEV,将为鸭病毒性肠炎的病原检测及分子流行病学调查等提供一种高效、快速、特异、灵敏的检测方法。     

牛疱疹病毒gD-PCR鉴别检测方法的建立

建立一种PCR技术,既能快速检测疱疹病毒1型成员牛传染性鼻气管炎病毒(bovine infectious rhinotracheitisvirus,IBRV),又能区分牛疱疹病毒5型和伪狂犬病毒。根据基因库中牛传染性鼻气管炎病毒的gD基因序列,应用primer 5.0软件设计了gD PCR引物,建立PCR方法,反应条件是:94℃预变性5min,94℃1min,58℃1min,72℃1min,30个循环,72℃7min,4℃5min。该方法能从IBRV阳性样本和参考毒株中扩增出372bp的目的片段,而从同属的牛疱疹病毒5型中扩增出440bp和206bp两条目的片段,从同属的伪狂犬病毒中扩增出303bp的目的片段,但不能从非疱疹病毒属成员猪呼吸与繁殖综合征病毒中扩增出目的条带。该PCR检测IBRV的灵敏度可达1PFU/mL以上。鉴于其灵敏度高、特异性好,可望在牛疱疹病毒感染快速鉴别检测方面发挥重要作用。     

Evaluation of the Usefulness of a PCR Assay Performed at a Clinical Laboratory for the Diagnosis of Respiratory Disease Induced by Equine Herpesvirus Type 1 in the Field

A PCR assay for the diagnosis of respiratory disease induced by equine herpesvirus type 1 (EHV-1) was performed at the clinical laboratory in the Racehorse Clinic of the Ritto Training Center of the Japan Racing Association from December 2007 to March 2008. The assay was performed without the trouble of contamination throughout the study and its turnaround time was approximately 6 hr. The PCR detection rates of EHV-1 among seroconverted horses were 22.2% for nasal swabs and 33.3% for blood samples. However, EHV-1 DNA was also detected in horses without seroconversion at a low rate. These results indicated that the PCR assay should be used as an adjunct method, but would help to make an early diagnosis of EHV-1 infection.     

Neuropathogenic and non-neuropathogenic genotypes of Equid Herpesvirus type 1 in Argentina

Infection with Equid Herpesvirus type 1 (EHV-1) leads to respiratory disease, abortion, and neurological disorders in horses. Molecular epidemiology studies have demonstrated that a single nucleotide polymorphism (A₂₂₅₄/G₂₂₅₄) in the genome region of the open reading frame 30 (ORF30), which results in an amino acid variation (N₇₅₂/D₇₅₂) of the EHV-1 DNA polymerase, is significantly associated with the neuropathogenic potential of naturally occurring strains. In order to estimate the prevalence of the EHV-1 neuropathogenic genotype in our country, we analyzed the ORF30 genome region of Argentinean EHV-1 isolates. The study was carried out by real time allelic discrimination PCR in 90 equine EHV-1-positive samples, being 89 from 54 cases of abortion outbreaks (two of which were in association with neurological disease) and one from the respiratory tract of a healthy horse in training. Our results indicate that 7% (4/54) of the abortion outbreaks studied were induced by the neuropathogenic (G₂₂₅₄) genotype of EHV-1 and 50% (2/4) of them were associated with simultaneous neurological disease. This information emphasizes the necessity to extreme the hygienic and preventive measures to diminish EHV-1 infections and consequently reduce the risk of epizootic neurological disease as has been recently observed in other countries.     

Detection and Management of an Outbreak of Equine Herpesvirus Type 1 Infection and Associated Neurological Disease in a Veterinary Teaching Hospital

Background: Because of the serious disease sequelae associated with equine herpesvirus type 1 (EHV‐1) infections, awareness and control measures used to control outbreaks are important issues for all horse populations. Objectives: Describe the occurrence and management of an outbreak of EHV‐1 infection at a veterinary hospital. Animals: Horses hospitalized at a referral veterinary hospital. Methods: A horse with myeloencephalopathy associated with EHV‐1 infection (EHM) was admitted for diagnostic evaluation and treatment under strict infection control procedures. We describe the occurrence and management of a nosocomial outbreak of EHV‐1 infections associated with admission of this patient. Results: Despite institution of rigorous biosecurity precautions at the time of admission of the index case, EHV‐1 infections spread to 6 other horses that were hospitalized at the James L. Voss Veterinary Teaching Hopsital, including 2 that served as sources of infection for horses on their home premises after discharge. Infection with EHV‐1 was confirmed by polymerase chain reaction (PCR) and by seroconversion documented by glycoprotein G ELISA. A voluntary quarantine was imposed and admissions were restricted to prevent additional horses from being exposed. Quarantine duration was abbreviated by serial testing of all horses with PCR. Conclusions and Clinical Importance: These findings illustrate the contagious disease risk that can accompany management of horses with EHM. Horses with active nasal EHV‐1 shedding should be isolated in an airspace that is separate from other horses by strictly enforced biosecurity and isolation procedures. Serial testing with PCR may be a useful adjunct to determine when the risk of transmission has been minimized.     

鸭2型疱疹病毒的分子生物学依据

鸭2型疱疹病毒，是一种可侵害番鸭、半番鸭等不同品种鸭的疱疹病毒科新成员，经生物学特性测定、血清学试验及致病性试验表明该病毒不同于鸭瘟病毒。采用SDS-PAGE分析表明该病毒的结构蛋白带有14条，主要结构蛋白带有7条，其分子量分别为310、163、95、79、69、39、15KD，不同于鸭瘟病毒。依据鸭瘟病毒UL6基因的序列，设计了一对引物，经PCR扩增、琼脂糖凝胶电泳表明只有鸭瘟病毒核酸提取物可扩增出大约420bp的DNA片段，而鸭2型疱疹病毒核酸提取物、鸡传染性喉气管炎病毒核酸提取物和正常细胞培养物均未扩增出目的基因片段，可见鸭2型疱疹病毒与鸭瘟病毒在DNA分子水平上也存在差异。本研究揭示了该病毒与鸭瘟病毒在结构蛋白和核酸水平上的差异，进一步表明该病毒不同于鸭瘟病毒，为该病毒的确切分类提供了分子生物学依据。     

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.     

多重PCR方法检测锦鲤疱疹病毒基因

根据对已报道的PCR检测方法灵敏性评价,以常用KHV病毒PCR检测的目的基因KHVSphI片段(AY568590)、KHV5/9(AF411803)和KHVTK基因(AJ535112)作为靶基因,设计并选择3对特异性引物建立的多重PCR检测体系用于KHV病毒多基因的检测。本研究建立的多重PCR体系具有较高的特异性,能够特异性扩增出KHVSphI片段290bp、KHV5/9片段484bp和KHVTK基因片段409bp,对锦鲤和鲤鱼的另外一种病毒性病原鲤春毒血症病毒检测结果为阴性。多重KHV病毒PCR体系检测KHVSphI、KHV5/9和KHVTK基因片段单一模板的检测下限分别为:10fg、100fg和100fg,在相同模板浓度的情况下,KHVSphI、KHV5/9和KHVTK基因片段同时被检出的检测下限为100fg。对KHV病毒感染组织的检测结果表明,多重KHV病毒PCR检测结果与常规PCR检测结果基本吻合,在多重PCR检测体系中KHVTK基因片段检测的灵敏度高于检验检疫行业标准方法。结果表明,多重KHV病毒PCR检测方法能够快速、准确和灵敏地检测KHV病毒基因。     

鸭甲型肝炎病毒1型与3型双重TaqMan实时荧光定量PCR检测方法的建立与应用

旨在建立一种针对鸭甲肝病毒1型（DHAV-1）和鸭甲肝病毒3型（DHAV-3）的高效快速、高灵敏度和高特异性的双重TaqMan实时荧光定量PCR （q-PCR）检测方法并应用于临床疑似样品检测。根据DHAV-1和DHAV-3的VP1基因保守区域,分别设计合成了2对特异性引物和探针,在此基础上建立并优化了双重TaqMan实时荧光定量PCR方法。结果显示：优化后标准曲线的相关系数（R²）均在0.999以上,扩增效率（E）在105%~110%,其组内变异系数（i-CV）与组间变异系数（c-CV）均在0.77%以下。运用双重q-PCR方法对不同稀释度的混合质粒与病毒核酸进行检测,结果表明,建立的双重TaqMan q-PCR特异性高;同时检测DHAV-1和DHAV-3的灵敏度均可达10个拷贝,分别是常规PCR方法的1 000倍和100倍。对40份来自苏中、苏北地区的疑似鸭肝炎病毒感染的鸭组织病料进行检测,结果表明,q-PCR方法检出36份阳性病料,阳性率为90%;而常规PCR方法未能检出高Ct值的样品,阳性率为72.5%（29份阳性病料）。建立的双重TaqManq-PCR检测方法为DHAV-1与DHAV-3的临床样品检测提供了高效、灵敏、特异的工具,推动了临床分子流行病学调查及病毒定量分析等研究。     

猪圆环病毒3型荧光定量PCR检测方法的建立及其在猪体中的组织分布研究

为了解猪圆环病毒3型(PCV3)在猪体中的组织分布情况,针对PCV3 Cap蛋白基因设计筛选出一对特异性引物和探针,通过对荧光PCR引物、探针浓度进行优化,建立了基于TaqMan探针实时荧光定量PCR技术的PCV3检测方法,并应用该方法对人工感染PCV3猪的多种组织器官进行病毒含量检测。结果显示,建立的PCV3实时荧光定量PCR检测方法特异性较好且灵敏度高,可检测低至1 copy/μL的PCV3病毒核酸量,而对其他几种常见猪病毒病原的检测结果均为阴性。PCV3主要存在于肺脏、淋巴结,在扁桃体和脾脏中有少量存在。试验表明,所建立的荧光定量PCR检测方法可用于PCV3的快速定量检测,对PCV3在猪体中的组织分布情况的研究为进一步揭示PCV3的组织嗜性和致病机理提供理论依据。     

检测马疱疹病毒4型抗体间接ELISA方法的建立及应用简

In order to establish an indirect ELISA method for detection of equine herpesviruses type 4 （EHV4） antibody, the glycoprotein G （gG） protein with specific epitope worked as a detection antigen. After optimizing conditions, the indirect ELISA method was developed successfully,specificity and repeatability tests were determined. The result was that the EHV4 gG only reacted with antibodies against EHV4;but not with antibodies against EHV1; both the intro-batch and inter-batch variation coefficiencies were lower than 10%.Concordance of the indirect ELISA relative to commercial EHV1/4 antibody kit was above 90%.The results indicated that the indirect ELISA method could be used for the detection and epidemiological surveys of EHV4 infection.     

猪圆环病毒2型巢式PCR检测方法的建立与初步应用

猪圆环病毒2型(porcine circovirus type 2,PCV2)给养猪业造成了重大的经济损失,建立经济、快速的检测方法尤为重要。本研究旨在利用巢式PCR技术,建立高灵敏度PCV2检测平台,以加强对猪圆环病毒病的防控。根据PCV2 ORF2基因保守区,设计内、外2对巢式PCR引物,通过优化PCR反应条件,建立巢式PCR检测方法,并对猪场临床样本进行检测。结果显示,本研究建立的巢式PCR检测方法灵敏度高、重复性强,最低检出量为10拷贝/μL,检出率达97.3%。本研究建立的巢式PCR检测方法为快速、高效地检测PCV2以及为猪圆环病毒病的防控提供有力手段。     

Establishment and Preliminary Application of Nested PCR for the Detection of Porcine Circovirus Type 2

Porcine circovirus type 2 (PCV2) caused significant economic losses of swine industry,it's very important to establish a economy and rapid detection method.To strengthen the prevention and control of porcine circovirus disease,rapid and high sesitive detection method of PCV2 was established using nested PCR.According to PCV2 ORF2 gene conservative region,we designed two pairs of nested PCR primers,constructed ORF2 gene recombinant plasmid for standard template and optimizated the PCR reaction conditions to establish nested PCR detection method of PCV2 and detect the clinical samples of pig farms.Our results showed that the sensitivity and repeatability of this method were very high,the minimum detection level was 10 copies/μL and detection rate of clinical samples was 97.3%.In brief,the established nested PCR detection method of PCV2 in this study provided powerful means for quick and efficient detection of PCV2,and prevention and control of porcine circovirus disease in the swine industry.     

牛疱疹病毒I型二重LUX荧光PCR鉴别检测方法的建立

采用LUX新型荧光PCR技术原理，建立了快速检测牛疱疹病毒I型（BHV-1）以及鉴别野毒感染和基因缺失疫苗免疫动物的二重实时荧光PCR方法。结果显示，该方法对多株BHV-1病毒均呈典型gE、gC双基因阳性反应，对其他常见动物疱疹病毒以及健康牛基因组DNA等均呈阴性反应；对细胞增殖病毒液的gE、gC双基因鉴别的检测敏感性可达0．4～O．04TCID50比常规PCR方法高100倍以上；对带毒牛血清、抗凝全血、牛新鲜精液和冷冻精液基因鉴别的检测敏感性分别达0．04TCID50、0．4TCID50、0．4TCID50和4TCID50。采用该方法从临床牛血样、鼻拭子样品中检出IBRV阳性样品，检测全程仅需约2h。对单基因克隆质粒的检测进一步证实该方法能特异地鉴定gE、gC基因，检测灵敏度分别达90、30拷贝。结果表明，该方法可应用于临床快速诊断BHV-1病毒感染，鉴别BHV-1病毒感染与对应的基因缺失疫苗免疫动物。     

1种布鲁氏菌微滴式数字PCR检测方法的建立

本研究旨在构建1种布鲁氏菌(Brucella)微滴式数字PCR方法(droplet digital PCR,ddPCR).以布鲁氏菌BCSP31基因为靶基因,选取保守区域设计引物和探针,构建了布鲁氏菌微滴式数字PCR方法.然后优化了ddPCR反应中的引物、探针浓度及退火温度,并进行方法的灵敏度、特异性和重复性试验.结果...     

牛副流感病毒3型3种基因型多重RT-PCR检测方法的建立

为建立检测牛副流感病毒3型（bovine parainfluenza virus type 3,BPIV3）3种基因型的多重RT-PCR方法,根据GenBank上发表的BPIV3 3种基因型病毒株的HN基因序列设计特异性引物,优化反应体系建立多重RT-PCR方法。结果显示,方法可同时扩增出BPIV3 A型150 bp、B型253 bp和C型342 bp的特异性片段,与牛传染性鼻气管炎病毒（IBRV）、牛呼吸道合胞体病毒（BRSV）、牛病毒性腹泻病毒（BVDV）、小反刍兽疫病毒（PPRV）、牛支原体、牛布鲁氏菌、羊布鲁氏菌、牛源多杀性巴氏杆菌A型和B型均无交叉反应,A、B、C基因型BPIV3最低阳性质粒检测量分别为0.89×10⁴、0.92×10⁴和1.53×10⁴拷贝/μL。本试验建立的多重RT-PCR检测方法操作方便、特异性强,应用于临床样本的检测,可快速检测BPIV3 3种基因型。