Characterization of two newly emerged isolates of porcine reproductive and respiratory syndrome virus from Northeast China in 2013.
A newly emerged porcine reproductive and respiratory syndrome virus (PRRSV) that has caused severe reproductive losses in sows appeared in some regions of China in 2013. To explore the biology of this new PRRSV and understand more fully genetic diversity in PRRSV isolates from China, the complete genome of the two 2013 Chinese isolates, designated HLJA1 and HLJB1, were analyzed. Genomic sequence analysis showed that HLJA1 and HLJB1 shared 88.6-98.3% nucleotide identity with genotype 2 (North American type, NA-type) isolates, but only 61.1% with the genotype 1 (European type, EU-type) isolate of Lelystad virus, indicating that both these isolates belong to the NA-type PRRSV genotype. Phylogenetic analysis showed that the NA-type PRRSV isolates formed three subgroups (1, 2 and 3); representatives of these subgroups are VR-2332, CH-1a and HUN4, respectively. HLJA1 and HLJB1 belong to subgroup 2. Analysis of NSP2 revealed that HLJA1 has a 48-amino acid deletion at positions 473-480 and 482-521, unlike other HP-PRRSV isolates, while HLJB1 has only a 1-amino acid deletion at position 481 compared with CH-1a. Interestingly, HLJA1 replicated in PAM cells but not in MARC-145 cells, whereas HLJB1 replicated in both cell types. The neutralizing antibody titer of pig hyperimmune sera against HUN4 was significantly higher than that of HLJA1 or HLJB1. Additionally, genetic variability in GP5 and GP3 proteins and in the novel ORF5a protein was evident. In addition to elucidating the genetic relationships between PRRSV isolates, our results suggest that Chinese PRRSV will remain a pandemic virus.
College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China.
Chao-liang
CL
Leng
State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China. Electronic address: tzj@hvri.ac.cn.
Zhi-jun
ZJ
Tian
State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China.
Wu-chao
WC
Zhang
State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China.
Hong-liang
HL
Zhang
State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China.
Hong-yue
HY
Zhai
State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China.
Tong-qing
TQ
An
State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China.
Jin-mei
JM
Peng
State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China.
Chao
C
Ye
College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China.
Long
L
Sun
State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China.
Qian
Q
Wang
State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China.
Yan
Y
Sun
State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China.
Lin
L
Li
State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China.
Hong-yuan
HY
Zhao
State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China.
Dan
D
Chang
State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China.
Xue-hui
XH
Cai
College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China. Electronic address: guihongzh@scau.edu.cn.
Gui-hong
GH
Zhang
College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China; Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China. Electronic address: gztong@shvri.ac.cn.
Guang-zhi
GZ
Tong
D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D002681:China; D014644:Genetic Variation; D005838:Genotype; D010802:Phylogeny; D019318:Porcine Reproductive and Respiratory Syndrome / Q000821:virology*; D019316:Porcine respiratory and reproductive syndrome virus / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D016415:Sequence Alignment; D017384:Sequence Deletion; D017386:Sequence Homology, Amino Acid; D013552:Swine
Genetic diversity; NSP2; ORF5a; PRRSV