Dengue is a pathogenic mosquito-borne virus belonging to the Flaviviridae family that causes 390 million infections per year. A safe, effective vaccine is needed.
Researchers used a variety of tobacco (Nicotiana benthamiana) to transiently express [virus-like particles, or] VLPs using technology pioneered at the John Innes Centre by Professor Lomonossoff. After extraction and purification, the VLPs were shown to stimulate an immune response to the virus in experiments on mice.
“This is the first of what would be many steps along the path towards making dengue vaccines in plants,” said corresponding author Dr Hadrien Peyret of the John Innes Centre.
Using the metabolism of plants to produce these valuable molecules potentially offers an affordable and low-tech solution to vaccine development.
VLPs are authentic mimics of the virus containing the protein coat but without the infectious material. This as the basis for a vaccine is enough to train the immune system without causing an infection.
“What we’ve made is not a candidate dengue vaccine: at best it’s a quarter of a candidate dengue vaccine. But for experts in this field the exciting aspect is the production and purification of enveloped VLPs in plants without using the influenza virus HA transmembrane domain which would have been an alternative strategy,” said Dr Peyret.