牛腺病毒5型TaqMan探针实时荧光定量PCR检测方法的建立

建立针对牛腺病毒5型六邻体(Hexon)基因的实时荧光定量TaqMan PCR检测方法。根据牛腺病毒5型Hexon基因高度保守区设计引物和TaqMan探针,绘制标准曲线,对其灵敏度、特异性、重复性进行验证,建立牛腺病毒5型实时荧光定量TaqMan PCR快速检测方法。结果显示,构建的重组质粒pUC57-BAV5,标准曲线在10~2～10~7拷贝数之间有较好的线性关系,相关系数为0.975 2,建立检测方法的最低检测限为32拷贝/μL;应用建立的方法检测牛传染性鼻气管炎病毒、牛轮状病毒、牛呼吸道合胞体病毒无交叉反应;重复性试验表明,同一浓度的20个平行样品的变异系数为1.4%。牛腺病毒5型TaqMan探针荧光定量PCR方法具有灵敏度高、特异性强、重复性好等特点,可以用于牛腺病毒5型的快速、准确的检测。     

鸭腺病毒3型Hexon基因的克隆及SYBR GreenⅠ实时荧光定量PCR方法的建立

鸭腺病毒3型(duck adenovirus type 3,DAdV-3)是近年来我国新发鸭源禽腺病毒。本试验根据NCBI数据库中DAdV-3 Hexon基因特征,设计特异性引物,获得番鸭源DAdV-3福建株(命名为W1FJ株)Hexon基因全长,明确其分子特征,并基于此建立检测DAdV-3的SYBR GreenⅠ实时荧光定量PCR方法。结果表明,克隆的W1FJ株Hexon基因全长为2 814 bp,编码937个氨基酸,和DAdV-3(CH-GD-12-2014株)核苷酸同源性为100%,但和鸭源禽腺病毒B型(也称鸭腺病毒2型,DAdV-2,GR株)核苷酸同源性仅为76.6%。Hexon蛋白遗传进化分析表明,W1FJ株和CH-GD-12-2014株在遗传进化上形成一个独立的分支,与鸭源禽腺病毒B型和鹅源禽腺病毒A型(goose aviadenovirus A)在遗传进化上明显不同,建议将其命名为鸭源禽腺病毒C型(duck aviadenovirus C)。建立的检测DAdV-3的SYBR GreenⅠ实时荧光定量PCR方法,灵敏度高,最低检测限为61拷贝/μL;特异性强,和鸭群常见传染病病原均无交叉反应,扩增产物的熔解曲线只出现1个特异性单峰,Tm值为(81.48±0.25)℃;重复性好,组内和组间重复试验变异系数分别为0.49%～1.64%和0.67%～2.40%。本试验为DAdV-3的科学分类和后续开展DAdV-3感染的流行病学调查及致病机理研究奠定基础。     

鸭痘病毒TaqMan荧光定量PCR检测方法的建立

为建立检测鸭痘病毒的TaqMan荧光定量PCR方法,本试验克隆了鸭痘病毒P4b基因,构建重组质粒pMD-DPV-P4b,并将其作为标准阳性模板。参照GenBank收录的禽痘病毒P4b基因设计合成1对特异性引物及与该引物相匹配的特异探针。以定量的10倍系列稀释的质粒pMD-DPV-P4b为标准品,通过对反应条件进行优化,建立了一种检测鸭痘病毒的TaqMan荧光定量PCR方法。结果显示,该方法与禽流感病毒、鸭黄病毒、鸭肝炎病毒、新城疫病毒、鸭瘟病毒和小鹅瘟病毒等其他水禽病毒,以及山羊痘病毒和鸡痘病毒等其他痘病毒均无交叉反应,特异性好。该方法最低检测限为1.29×10²拷贝/μL,比普通PCR检测方法高100倍。组内和组间变异系数均小于2%。结果表明,本试验所建立方法具有灵敏、特异、安全、快速的特点,适用于鸭痘病毒的检测。     

鸭腺病毒3型SYBR GreenⅠ实时荧光定量PCR检测方法的建立与应用

为建立鸭腺病毒3型(duck adenovirus 3,DAdV-3)一种基于SYBR Green I染料的荧光定量PCR诊断方法,本试验根据DAdV-3基因组序列中相对保守的Fiber-2基因,通过普通PCR扩增,构建pMD19-Fiber2重组质粒为阳性标准品,在此基础上设计合成特异性引物进行实时荧光定量PCR方法的建立,对其灵敏性、特异性和重复性进行评价,并初步应用于临床样本检测。结果显示,针对DAdV-3的Fiber-2基因建立的SYBR Green I荧光定量PCR检测方法线性关系良好,相关系数0.998 9;检测DAdV-3的灵敏度为3.6×10² copies/μL,敏感性比普通PCR检测方法高100倍;该方法对鸭腺病毒1型、鸭疫里默杆菌等其他常见病原均无交叉扩增反应,批内、批间变异系数均小于5%;临床样本检测与普通PCR符合率100%。以上结果表明,所建方法特异性强、敏感性高且重复性好,适用于临床检测,该方法可为DAdV-3的临床诊断、流行病学调查以及防控提供技术支持。     

实时荧光定量TaqMan-PCR检测鸭瘟病毒方法的建立

根据GenBank中鸭瘟病毒UL6和UL7基因的序列,设计了一对特异性引物及TaqMan探针,扩增位于UL6和UL7基因第891￣991位长度为101bp片段。以DPV标准强株DNA为模板,建立了实时荧光定量PCR检测鸭瘟病毒的方法。该方法只能在鸭瘟病毒DNA样本中检出荧光信号,最小检出量为1.57×102copies(23.7fg);线性范围达8个数量级;平行复管检测,组内变异系数为0.84%(n=20),同一组样本(n=6)间隔30d重复检测,结果无显著性差异;对试验感染鸭肝脏和脑组织中鸭瘟病毒的检出率为100%(40/40),对临床病例的检测结果与病毒分离鉴定结果一致;从核酸提取到报告检测结果仅需3h;对鸭正常组织、鸡传染性喉气管炎病毒、鸭病毒性肝炎病毒、鸡源大肠杆菌、鸭源多杀性巴氏杆菌、鸭副伤寒沙门氏菌等非鸭瘟病毒DNA检测,不出现非特异性荧光信号。     

鸭甲肝病毒2型TaqMan实时荧光定量PCR方法的建立

研究利用全基因合成技术合成DHAV-2全基因组序列,并以此为标准品建立检测DHAV-2的TaqMan实时荧光定量PCR方法。结果表明:建立的方法敏感性高,最低检测限仅为33.7拷贝/μL;特异性强,对鸭甲肝病毒1型(DHAV-1)、鸭甲肝病毒3型(DHAV-3)、禽流感病毒(Avian influenza virus,AIV)、番鸭呼肠孤病毒(Muscovy duck reovirus,MDRV)、新型鸭呼肠孤病毒(Novel duck reovirus,N-DRV)、鸭源禽Ⅰ型副黏病毒(Duck-origin avian paramyxovirus type 1,APMV-1)和禽坦布苏病毒(Avian Tembusu virus,ATmV)均无交叉扩增;重复性佳,组内和组间变异系数最高分别为1.68%和2.19%。对2018年福建地区临床收集的128份鸭源病料进行检测,结果未检测DHAV-2感染阳性。研究结果为DHAV-2的快速检测试剂盒研究及储备DHAV-2检测技术奠定了基础。     

马疱疹病毒8型TaqMan实时荧光定量PCR检测方法的建立

为了建立一种能够快速检测马疱疹病毒8型(EHV-8)的方法,本试验以EHV-8的全基因组序列为模板,针对糖蛋白B(gB)基因的保守序列,进行对比分析,设计EHV-8的特异性引物和探针,优化反应条件,建立EHV-8 TaqMan实时荧光定量PCR检测方法,并对该方法的敏感性、特异性和重复性进行验证,使用该方法进行临床样本检测。结果显示,建立的EHV-8 TaqMan实时荧光定量PCR检测方法对EHV-8 DNA模板的最低检测限为1.1×10² copies/μL,敏感性高;EHV-8与EHV-1、EHV-4、马流产沙门氏菌和肠产毒性大肠杆菌均无交叉反应,特异性强;批内重复性试验和批间重复性试验均表明该方法重复性好。对132份临床样本的检测结果显示,阳性检出率为10.61%,基因测序正确。由此可见,本试验建立的EHV-8 TaqMan实时荧光定量PCR检测方法能够满足EHV-8的检测需求,且该方法敏感性高、特异性强、重复性好,为EHV-8的进一步研究提供了有效的辅助检测手段。     

鸭坦布苏病毒TaqMan荧光定量PCR方法的优化

为提高鸭坦布苏病毒(DTMUV)TaqMan荧光定量PCR方法的敏感性和简化反应条件,本研究在前期建立的TaqMan荧光定量PCR方法的基础上,设计一条特异性的反转录引物,优化反应体系,建立了简便、快速、敏感的TaqMan荧光定量PCR方法。该荧光定量PCR方法最低检测限为10拷贝,敏感性是未优化的荧光定量PCR方法的5倍、是普通PCR方法的100倍,并且该方法对DTMUV的最低检测限是0.01半数鸡胚致死量(ELD50)。通过批内和批间实验的变异系数表明优化的荧光定量PCR方法的重复性比未优化的荧光定量PCR方法好。通过该优化的荧光定量PCR方法检测其它常见的鸭病病毒的DNAs或RNAs,证明了该方法特异性好。对现地60份疑似DTMUV的样品进行检测,用该方法检出57份样品为阳性,明显高于普通PCR,并且在区分35Ct值左右样品试验中敏感性优于未优化的荧光定量PCR方法。该优化的DTMUV TaqMan荧光定量PCR方法更适用于DTMUV的快速定量流行病学诊断。     

Establishment of TaqMan Real-time PCR Method for Detection of Duck Poxvirus

To establishment a TaqMan Real-time PCR method for detection of duck poxvirus (DPV),we cloned the P4b gene of DPV.The specific primers and probe were designed according to the nucleotide sequence of avipoxvirus available in GenBank.Recombinant plasmid pMD-DPV-P4b was employed as positive standard template for Real-time PCR.By optimization of reaction conditions,a TaqMan Real-time PCR method for detection of DPV was established.The results of specificity test proved this method had no cross-react with other waterfowl vial agents and poxviruses including avian influenza virus,duck flavivirus,duck hepatitis virus,Newcastle disease virus,duck entertitis virus,goose parvovirus,goatpox virus and fowlpox virus.The detection limit of the assay was 1.29×10² copies/μL of viral DNA,which was 100 times higher than that of the routine PCR.Reproducibility test showed that the CVs of intra assay and inter assay were both less than 2%.Above results supported that the assay was suitable for the detection of DPV very well.     

鸭副黏病毒和鸭圆环病毒二重荧光定量PCR检测方法的建立

根据鸭副黏病毒(DPMV)和鸭圆环病毒(DuCV)保守基因序列,设计了2对针对鸭副黏病毒和鸭圆环病毒的特异性引物和2条不同荧光基团标记的TaqMan探针,建立了鸭副黏病毒和鸭圆环病毒的二重荧光定量PCR检测方法。该方法敏感性好,对鸭副黏病毒和鸭圆环病毒的检测敏感性分别达到160和140个拷贝数;该方法特异性强,对鸭肝炎病毒、番鸭细小病毒、鸭瘟病毒和H9型禽流感病毒等病原体的检测全为阴性;应用该方法对118份临床病料进行检测,结果检出鸭副黏病毒和鸭圆环病毒阳性感染率分别为0.85%和8.47%,无混合感染。本试验建立的二重荧光定量PCR具有快速、特异、敏感和重复性好等优点,适用于鸭副黏病毒和鸭圆环病毒的快速诊断和监测。     

Cloning and Sequence Analysis of Hexon Gene of Duck Adenovirus A

In order to clarify the characteristics of the Hexon gene and the classification candidate of duck adenovirus A under the Adenoviridae family, the Hexon gene fragments of duck adenovirus A (designated as strain JX2016) were amplified. The results demonstrated that the cloned Hexon gene of duck adenovirus A (strain JX2016) was 2 733 bp in length, coding 910 amino acids. Nucleotide homology comparison showed that the strain JX2016 shared the highest nucleotide (99.8%) homology with reference strain FJ12025, also displayed higher than 99.4% nucleotide homology with other duck adenovirus A reference strains. However, the nucleotide homologies with strain GR (duck adenovirus 2, unclassified virus), Phelps (fowl adenovirus A) and P29 (goose adenovirus) were 54.5%, 53.6% and 55.2%, respectively. The genetic evolution analysis showed that all the duck adenovirus A strains were at the same subgroup, under the same Atadenovirus genus branch with ovine atadenovirus D (strain OAV287). Meanwhile, the duck adenovirus 2 (strain GR) at the same branch under Aviadenovirus genus branch with fowl adenovirus A (strain Phelps) and goose adenovirus (strain P29). Based on the Hexon protein genetic evolution analysis, we suggested renamed the duck adenovirus A as duck-origin atadenovirus and renamed the duck adenovirus 2 as duck-origin aviadenovirus.     

鸭腺病毒A型Hexon基因克隆与序列分析

为明确鸭腺病毒A型Hexon基因特征及其在腺病毒科病毒分类中的作用,本研究从前期分离鉴定的一株番鸭源鸭腺病毒A型分离株（JX2016株）中分段扩增获得其Hexon基因编码区。结果发现,鸭腺病毒A型JX2016株Hexon基因编码区为2 733 bp,编码910个氨基酸,与鸭腺病毒A型（FJ12025株）核苷酸同源性最高,达99.8%;与其他分离株Hexon基因核苷酸同源性均在99.4%以上;与鸭腺病毒2型（GR株,未明确分类地位）同源性仅为54.5%;与禽腺病毒A型Phelps株（鸡源）及P29株（鹅源）的核苷酸同源性分别为53.6%和55.2%。遗传进化树分析发现,所有鸭腺病毒A型分离株在遗传进化上均处于相同的亚分支,且与绵羊腺病毒D型（OAV287株）均处于富AT腺病毒属遗传进化分支。但鸭腺病毒2型（GR株）与禽腺病毒A型Phelps株（鸡源）、P29株（鹅源）却处于同一遗传进化分支,均属于禽腺病毒属遗传进化分支。基于Hexon蛋白的遗传进化分析,建议将鸭腺病毒A型重新命名为鸭源富AT腺病毒A型,将鸭腺病毒2型重新命名为鸭源禽腺病毒。     

血清1型鸭甲型肝炎病毒实时定量PCR检测方法的建立与初步应用

为建立了一种可检测血清1型鸭甲型肝炎病毒（DHAV-1）的实时定量PCR方法,根据GenBank中DHAV-1 5,非编码区的保守区,设计合成1对引物和1条TaqMan探针,以构建的重组质粒作为标准品,绘制标准曲线,并对所建立方法进行了特异性、敏感性和可重复性试验以及临床病料检测初步应用。结果,该方法与血清3型鸭甲型肝炎病毒、鸭瘟病毒、新城疫病毒、禽流感病毒、呼肠孤病毒、传染性支气管炎病毒等无交叉反应性;最低可以检测到10copies/μL;组内和组间变异系数均小于3%;临床病料的检测结果与测序检测结果一致。结果表明,所建立的实时定量检测方法具有特异、敏感、稳定等优点,可用于DHAV-1的快速检测与定量分析。     

化脓隐秘杆菌TaqMan实时荧光定量PCR检测方法的建立

本试验旨在建立检测化脓隐秘杆菌(Arcanobacterium pyogenes,A.pyogenes)特异、灵敏的TaqMan实时荧光定量PCR检测方法。根据GenBank公布的化脓隐秘杆菌溶血素(pyolysin,PLO)基因高保守序列,设计特异性引物和探针建立检测体系,用于化脓隐秘杆菌的快速检测,并对该方法的特异性和灵敏度进行检测。结果显示,本试验建立的TaqMan实时荧光定量PCR方法仅对化脓隐秘杆菌的检测结果为阳性;该方法最低检测DNA浓度为77.6 fg,最低检测细菌浓度为63 CFU/mL。采用本研究建立的方法检测23份林麝临床病例样品,共鉴定出16株化脓隐秘杆菌,与API Coryne生化鉴定方法的结果相同。本研究为化脓隐秘杆菌的检测提供了一种灵敏、特异、快速的检测方法,其可用于化脓隐秘杆菌的诊断和流行病学调查。     

Establishment of TaqMan Real-time PCR Assay for Detection of Arcanobacterium pyogenes

The study was aimed to establish a specific and sensitive TaqMan Real-time PCR assay for detection of Arcanobacterium pyogenes (A.pyogenes).Based on the conservative sequence of pyolysin (PLO) gene of A.pyogenes published in GenBank, specific primers and TaqMan probes were designed. The TaqMan Real-time PCR assay was established, and the specificity and sensitivity were tested.The specificity test results showed that only A.pyogenes exhibited typical curves.The detection sensitivity of this assay was 77.6 fg genomic DNA per 20 μL reaction, and 63 CFU/mL for pure cultures.16 out of 23 clinical samples were positive detected by the TaqMan Real-time PCR assay, which were consistent with API Coryne identification.The TaqMan Real-time PCR assay developed in this study was specific and sensitive for detection of A.pyogenes, and it could be used for identification and epidemiological investigation of A.pyogenes.     

猪劳森氏胞内菌TaqMan荧光定量PCR检测方法的建立

为建立一种快速有效的检测猪劳森氏胞内菌(LI)的方法,本研究根据该菌的天冬氨酸氨裂解酶基因保守序列设计合成一对特异性引物和一条TaqMan探针,建立了定量检测LI的荧光定量PCR方法,并对其进行敏感性、特异性、稳定性试验以及与套氏PCR方法的比较试验.结果表明,标准曲线的循环阈值与模板浓度呈现良好的线性关系,相关系数为0.998507;该方法对其他病原体的检测无特异性荧光信号;而且该方法灵敏度高于套式PCR方法.本研究为猪LI的检测提供了一种特异、敏感、快速的定量检测方法.     

Establishment of a Duplex TaqMan Real-time PCR Method for Detection of Bovine Viral Diarrhea Virus Types 1 and 2

【Objective】 This study was aimed to establish a duplex TaqMan Real-time PCR method for rapid detection of Bovine viral diarrhea virus types 1(BVDV1) and 2(BVDV2).【Method】 Specific primers were designed based on the 5'-non-coding region of 95 strains of BVDV1 and BVDV2 in GenBank.The positive plasmids containing the target fragments of BVDV1 and BVDV2 were constructed.The reaction conditions were optimized, the standard curve was constructed, the specificity, sensitivity and reproducibility of the duplex TaqMan Real-time PCR method were tested, and the established duplex TaqMan Real-time PCR assay was used to detect the clinical samples collected from Jilin province.【Result】 The results showed that the optimal annealing temperature of the duplex TaqMan Real-time PCR was 57.0 ℃, the optimum primer concentration was 0.5 μmol/L, and the optimum probe concentration was 0.3 μmol/L.The standard curves of BVDV1 and BVDV2 were Y=-3.54X+37.36 (R²=0.990) and Y=-3.18X+35.95 (R²=0.997), respectively.There was no specific amplification of Infectious bovine rhinotracheitis virus (IBRV), Bovine respiratory syncytial virus (BRSV) and Bovine parainfluenza virus type 3 (BPIV3), with intra- and inter-batch CV less than 3%, and the lower limit of detection was 10 copies/μL.The results of clinical samples showed that the overall positive rate was 23.1% (36/156), of which 17.9% (28/156) were positive for BVDV1 and 5.1% (8/156) were positive for BVDV2.【Conclusion】 In this study, a duplex TaqMan Real-time PCR method was established, which could identify BVDV types 1 and 2 simultaneously, quickly and accurately, and provided technical support for the prevention, control and purification of BVDV.