猪Ⅱ型圆环病毒(PCV2)Henan株的分离与全基因组序列分析

Isolation and Genomic Sequence Analysis of Porcine Circovirus Type 2(PCV2) Henan Strain

用PCR方法从河南某猪场送检的1头疑似断奶仔猪多系统衰竭综合征病猪的腹股沟淋巴结中检测到了猪Ⅱ型圆环病毒（porcine circovirus type2，PCV2）核酸。将该病料研磨、过滤除菌后接种无PCV1和PCV2污染的PK-15细胞，盲传12代后，用PCR方法仍然能够在接种细胞中检测到PCV2核酸。从接种细胞中收获病毒，经超速离心纯化后电镜负染观察．可见直径约17nm、呈二十面体对称结构的病毒粒子，表明从发病猪中分离到了PCV2，将该毒株命名为PCV2Henan株。序列分析表明：该株病毒全基因组长1767bp，包含11个读码框，与PCV1同源性为76．2％～77．3％，与其他PCV2株的同源性为95．5％～99．6％。

The nucleic acid fragments of PCV2 were detected from the tissues of clinical pigs with postweaning multisystemic wasting syndrome（PMWS）. The positive samples were homogenized in TE（pH8.0） and filtered. The suspension was inoculated in PCV1 free PK-15 cells. After 12 passages,one isolate of porcine circovirus type 2 was isolated and named PCV2 Henan. Purified virus was observed in transmission electron microscope. Virus was a 17 nm in diameter and icosahedral virion. The result of sequence analysis showed that Henan isolate＇s complete genome was composed of 1 767 nucleotides containing 11 ORFs. Compared with PCV1 and PCV2 reference strains from GenBank ,genome of Henan isolate shared 76. 2%-77.3% homology with PCV1 and 95.5%0-99. 6% homology with PCV2.