Influenza virus-like particles produced by transient expression in Nicotiana benthamiana induce a protective immune response against a lethal viral challenge in mice
Article first published online: 12 NOV 2008
© 2008 Medicago Inc. Journal compilation © 2008 Blackwell Publishing Ltd
Plant Biotechnology Journal
Volume 6, Issue 9, pages 930–940, December 2008
How to Cite
D’Aoust, M.-A., Lavoie, P.-O., Couture, M. M.-J., Trépanier, S., Guay, J.-M., Dargis, M., Mongrand, S., Landry, N., Ward, B. J. and Vézina, L.-P. (2008), Influenza virus-like particles produced by transient expression in Nicotiana benthamiana induce a protective immune response against a lethal viral challenge in mice. Plant Biotechnology Journal, 6: 930–940. doi: 10.1111/j.1467-7652.2008.00384.x
- Issue published online: 12 NOV 2008
- Article first published online: 12 NOV 2008
- Received 30 April 2008; revised 5 September 2008; accepted 19 September 2008.
- Nicotiana benthamiana;
- transient expression;
- virus-like particle
A strain-specific vaccine represents the best possible response to the threat of an influenza pandemic. Rapid delivery of such a vaccine to the world's population before the peak of the first infection wave seems to be an unattainable goal with the current influenza vaccine manufacturing capacity. Plant-based transient expression is one of the few production systems that can meet the anticipated surge requirement. To assess the capability of plant agroinfiltration to produce an influenza vaccine, we expressed haemagglutinin (HA) from strains A/Indonesia/5/05 (H5N1) and A/New Caledonia/20/99 (H1N1) by agroinfiltration of Nicotiana benthamiana plants. Size distribution analysis of protein content in infiltrated leaves revealed that HA was predominantly assembled into high-molecular-weight structures. H5-containing structures were purified and examination by transmission electron microscopy confirmed virus-like particle (VLP) assembly. High-performance thin layer chromatography analysis of VLP lipid composition highlighted polar and neutral lipid contents comparable with those of purified plasma membranes from tobacco plants. Electron microscopy of VLP-producing cells in N. benthamiana leaves confirmed that VLPs accumulated in apoplastic indentations of the plasma membrane. Finally, immunization of mice with two doses of as little as 0.1 µg of purified influenza H5-VLPs triggered a strong immune response against the homologous virus, whereas two doses of 0.5 µg of H5-VLPs conferred complete protection against a lethal challenge with the heterologous A/Vietnam/1194/04 (H5N1) strain. These results show, for the first time, that plants are capable of producing enveloped influenza VLPs budding from the plasma membrane; such VLPs represent very promising candidates for vaccination against influenza pandemic strains.