Expression of the nucleocapsid protein of Porcine Reproductive and Respiratory Syndrome Virus in soybean seed yields an immunogenic antigenic protein
Porcine reproductive and respiratory syndrome (PRRS), caused by the PRRS virus (PRRSV), is a serious disease of swine and contributes to severe worldwide economic losses in swine production. Current vaccines against PRRS rely on the use of an attenuated-live virus; however, these are unreliable. Thus, alternative effective vaccines against PRRS are needed. Plant-based subunit vaccines offer viable, safe, and environmentally friendly alternatives to conventional vaccines. In this study, efforts have been undertaken to develop a soybean-based vaccine against PRRSV. A construct carrying a synthesized PRRSV-ORF7 antigen, nucleocapsid N protein of PRRSV, has been introduced into soybean, Glycine max (L.) Merrill. cvs. Jack and Kunitz, using Agrobacterium-mediated transformation. Transgenic plants carrying the sORF7 transgene have been successfully generated. Molecular analyses of T0 plants confirmed integration of the transgene and transcription of the PRRSV-ORF7. Presence of a 15-kDa protein in seeds of T1 transgenic lines was confirmed by Western blot analysis using PRRSV-ORF7 antisera. The amount of the antigenic protein accumulating in seeds of these transgenic lines was up to 0.65% of the total soluble protein (TSP). A significant induction of a specific immune response, both humoral and mucosal, against PRRSV-ORF7 was observed following intragastric immunization of BALB/c female mice with transgenic soybean seeds. These findings provide a ‘proof of concept’, and serve as a critical step in the development of a subunit plant-based vaccine against PRRS.
KeywordsPRRS viral subunit Plant-based vaccine Transgenic soybean Immunogenicity
This research was supported by DOE-CPBR project GO12026-220.
- Bernard NF, David MK, Peter MH (1996) Fields virology. Lippincott-Raven Publishers, PhiladelphiaGoogle Scholar
- Chia M-Y, Hsiao S-H, Chan H-T, Do Y-Y, Huang P-L, Chang H-W, Tsai Y-C, Lin C-M, Pang VF, Jeng C-R (2011) Evaluation of the immunogenicity of a transgenic tobacco plant expressing the recombinant fusion protein of GP5 of porcine reproductive and respiratory syndrome virus and B subunit of Escherichia coli heat-labile enterotoxin in pigs. Vet Immunol Immunopathol 140:215–225PubMedCrossRefGoogle Scholar
- Darwich L, Gimeno M, Sibila M, Diaz I, de la Torre E, Dotti S, Kuzemtseva L, Martin M, Pujols J, Mateu E (2011) Genetic and immunobiological diversities of porcine reproductive and respiratory syndrome genotype I strains. Vet Microbiol. doi: 10.1016/j.vetmic.2011.01.008
- Dea S, Deen J, Rossow K et al (2002) Mechanical transmission of porcine reproductive and respiratory syndrome virus throughout a coordinated sequence of events during cold weather. Can J Vet Res 66:232–239Google Scholar
- Monger W, Alamillo JM, Sola I, Perrin Y, Bestagno M, Burrone OR, Sabella P, Plana-Duran J, Enjuanes L, Garcia JA, Lomonossoff GP (2006) An antibody derivative expressed from viral vectors passively immunizes pigs against transmissible gastroenteritis virus infection when supplied orally in crude plant extracts. Plant Biotechnol J 4:623–631PubMedCrossRefGoogle Scholar
- Rosales-Mendoza, S, Soria-Guerra, R, Moreno Fierros L, Herrera-Díaz A, Korban SS, Alpuche-Solís AG (2011) Immunogenicity of nuclear encoded LTB:ST fusion protein from Escherichia coli expressed in tobacco plants. Plant Cell Rep, doi: 10.1007/s00299-011-1023-0 (in press)
- Soria-Guerra R, Alpuche-Solís A, Rosales-Mendoza S, Moreno-Fierros L, Bendik EM, Martinez-Gonzales L, Korban SS (2009) Transplastomic tobacco plants expressing a multi-epitope fusion DPT protein retain antigenicity and immunogenicity of all three components. Planta 229:1293–1302PubMedCrossRefGoogle Scholar