HP-PRRSV is attenuated by de-optimization of codon pair bias in its RNA-dependent RNA polymerase nsp9 gene

Li Gao; Lianghai Wang; Chen Huang; Longlong Yang; Xue-Kun Guo; Zhibin Yu; Yihao Liu; Peng Yang; Wen-Hai Feng

doi:10.1016/j.virol.2015.07.012

HP-PRRSV is attenuated by de-optimization of codon pair bias in its RNA-dependent RNA polymerase nsp9 gene

Virology. 2015 Nov:485:135-44. doi: 10.1016/j.virol.2015.07.012. Epub 2015 Aug 4.

Authors

Li Gao¹, Lianghai Wang², Chen Huang², Longlong Yang³, Xue-Kun Guo², Zhibin Yu², Yihao Liu², Peng Yang⁴, Wen-Hai Feng⁵

Affiliations

¹ China Academy of Medicine Sciences, Peking Union Medical College, Institute of Medicinal Plant Development, Beijing 100193, China.
² State Key Laboratory of Agrobiotechnology, Department of Microbiology and Immunology, College of Biological Sciences, China Agricultural University, Beijing 100193, China; Department of Microbiology and Immunology, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
³ The Hamner Institutes for Health Sciences, Research Triangle Park, NC 27709-2137, USA.
⁴ Beijing Senkang Biotech Development Co., Ltd, Beijing 101400, China.
⁵ State Key Laboratory of Agrobiotechnology, Department of Microbiology and Immunology, College of Biological Sciences, China Agricultural University, Beijing 100193, China; Department of Microbiology and Immunology, College of Biological Sciences, China Agricultural University, Beijing 100193, China. Electronic address: [email protected].

PMID: 26247624
DOI: 10.1016/j.virol.2015.07.012

Abstract

There is an urgent need to develop new vaccines against highly pathogenic PRRS virus (HP-PRRSV) variant in China. The actual use of each codon pairs is more or less frequent than that of the statistical prediction and codon pair bias (CPB) usage affects gene translation. We "shuffled" the existing codons in HP-PRRSV genes GP5, M, nsp2 and nsp9, so that the CPB of these genes could be more negative. De-optimization of nsp9, the RNA-dependent RNA polymerase, significantly decreased PRRSV replication in porcine alveolar macrophages (PAMs). In vitro study showed that HV-nsp9(min) and HV-nsp29(min) were remarkably attenuated in PAMs, and inoculation of pigs with 2 ml⁎10(5.0) TCID50/ml of HV-nsp9(min) or HV-nsp29(min) did not cause PRRS. Importantly, pigs immunized with HV-nsp29(min) were fully protected against different HP-PRRSV strains׳ lethal challenges. Our results imply that the CPB de-optimized HV-nsp29(min) has the potential to be used as a live vaccine candidate against HP-PRRSV.

Keywords: Attenuation; Codon pair bias; HP-PRRSV; RNA dependent RNA polymerase; Vaccine.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Antibodies, Neutralizing / biosynthesis
Antibodies, Viral / biosynthesis
Codon / chemistry*
Codon / immunology
Genetic Engineering
Immunization
Macrophages, Alveolar / drug effects*
Macrophages, Alveolar / immunology
Macrophages, Alveolar / virology
Porcine Reproductive and Respiratory Syndrome / immunology
Porcine Reproductive and Respiratory Syndrome / mortality
Porcine Reproductive and Respiratory Syndrome / prevention & control*
Porcine Reproductive and Respiratory Syndrome / virology
Porcine respiratory and reproductive syndrome virus / drug effects*
Porcine respiratory and reproductive syndrome virus / genetics
Porcine respiratory and reproductive syndrome virus / immunology
Protein Biosynthesis
RNA-Dependent RNA Polymerase / administration & dosage
RNA-Dependent RNA Polymerase / genetics
RNA-Dependent RNA Polymerase / immunology*
Survival Analysis
Swine
Vaccines, Attenuated
Viral Load
Viral Proteins / administration & dosage
Viral Proteins / genetics
Viral Proteins / immunology*
Viral Vaccines / administration & dosage
Viral Vaccines / genetics
Viral Vaccines / immunology*
Virus Replication / drug effects

Substances

Antibodies, Neutralizing
Antibodies, Viral
Codon
Vaccines, Attenuated
Viral Proteins
Viral Vaccines
RNA-Dependent RNA Polymerase