Epitope mapping and characterization of a novel Nsp10-specific monoclonal antibody that differentiates genotype 2 PRRSV from genotype 1 PRRSV

Virology Journal

Xin Guo¹  Hanchun Yang¹  Xinna Ge¹  Zhibang Zhang¹  Lei Zhou¹  Xuexia Wen¹  Jianguo Dong¹ 

[1] Key Laboratory of Animal Epidemiology and Zoonosis of the Ministry of Agriculture, College of Veterinary Medicine and State Key Laboratory of Agrobiotechnology, China Agricultural University;

关键词: Porcine reproductive and respiratory syndrome virus (PRRSV);    Non-structural protein 10 (Nsp10);    Monoclonal antibody (mAb);    B-cell epitope;    Differential diagnosis;   

DOI  :  10.1186/s12985-017-0782-9

来源: DOAJ

【 摘 要 】

Abstract Background Porcine reproductive and respiratory syndrome virus (PRRSV), the causative agent of PRRS, has two distinct and highly diverse genotypes (genotype 1 and genotype 2) in the field. Accurate diagnosis and differentiation of the two genotypes of PRRSV are critical to the effective prevention and control of PRRS. The non-structural protein 10 (Nsp10) plays a vital role in viral replication and is one of the most conserved proteins of PRRSV, thus constituting a good candidate for PRRSV diagnosis. Results In this study, we generated a monoclonal antibody (mAb) 4D9 against Nsp10 by immunizing BALB/c mice with purified recombinant Nsp10 expressed by an Escherichia coli system. Through fine epitope mapping of mAb 4D9 using a panel of eukaryotic expressed polypeptides with GFP-tags, we identified the motif 286AIQPDYRDKL295 as the minimal unit of the linear B-cell epitope recognized by mAb 4D9. Protein sequence alignment indicated that 286AIQPDYRDKL295 was highly conserved in genotype 2 PRRSV strains, whereas genotype 1 PRRSV strains had variable amino acids in this motif. Furthermore, a mutant of the motif carrying two constant amino acids of genotype 1 PRRSV, Cys290 and Glu293, failed to react with mAb 4D9. More importantly, the mAb 4D9 could differentiate genotype 2 PRRSV strains from genotype 1 PRRSV strains using Western blotting and immunofluorescence analysis. Conclusion Our findings suggest that Nsp10-specific mAb generated in this study could be a useful tool for basic research and may facilitate the establishment of diagnostic methods to discriminate between genotype 1 and genotype 2 PRRSV infection.

【 授权许可】

Unknown