马立克氏病血清I型致瘤株病毒感染的早期检测

马立克氏病 (MD)是养禽业最重要的疫病之一 ,一直缺少有效的早期诊断方法。根据血清I型马立克氏病毒(MDV1)meq基因的核酸序列设计了一对寡苷酸核引物 ,分别对MDV1致瘤株 (京 - 1株 )、非致瘤株 (MD11/ 75C株、CV1988株 )、MDV2 (SB 1株 )、HVT(Fc 12 6株 )的核酸进行扩增。结果表明 :京 - 1株扩增到约 1 15kb核酸片段 ,MD11/ 75C株和CVI988株扩增到约 1 0kb核酸片段 ,而SB 1株、Fc 12 6株没得到任何扩增产物。PCR产物Dotblot结果显示 ,京 - 1株、MD11/ 75C株和CVI988株的扩增产物都与Digoxigenin标记的meq基因探针杂交 ,说明都是特异性的扩增产物。对MSB1细胞DNA及MDV感染鸡的血液及肝、肾肿瘤等DNA扩增都得到 1 15kb条带。将京 - 1株和CVI988株感染的细胞DNA混合再扩增 ,同时得到 1 15kb和 1 0kb的核酸条带 ,所以根据扩增产物大小可以区别致瘤株京 - 1株及非致瘤株CV1988株 ,这表示可从CVI988株病毒免疫鸡体内检测到MDV强毒 ,适于早期确诊强毒感染。

Early Detection of Oncogenic and Pathogenic Serotype I Marek's Disease Virus

Marek's disease is one of the most important infectious diseases in poultry farm, but still there are lack of effective methods for diagnosing it. A polymerase chain reaction(PCR) assay based on primers flanking meq gene of oncogenic MDV1 (J-l strain) was developed. These primers amplified a 1.15kb nucleotide band from oncogenic strain J-1 and a 1.0kb band from non-oncogenic strains(MD11/75c, CVI988). The MDV1 specific primers didn't amplify MDV2(SB-1) and HVT(Fc-126) DNA. Dot blot of the PCR products showed that the products of strains J-1,MD11/75c and CVI988 could hybridize with meq gene probe (labeled by digoxigenin). Mixing the J-1 DNA with CVI988 DNA as template, the results indicated the primers could amplify the two bands(1.15kb and 1.0kb) from the mixture, these primers can also amplify meq gene from MSB1 cell line and also from blood and tumor samples of J-l infected chickens. Therefore, using this primer, we can distinguish between oncogenic and non-oncogenic strain of MDV1.