QuotePlants have been used to produce a new vaccine against poliovirus in what is hoped to be a major step towards global eradication of the disease.
A cross-cutting team of scientists, including Dr Johanna Marsian working in Professor George Lomonossoff's Lab at the John Innes Centre, Norwich, has produced the novel vaccine with a method that uses virus-like particles (VLPs) - non-pathogenic mimics of poliovirus which are grown in plants.
https://medicalxpress.com/news/2017-08-plant-produced-polio-vaccines-eradicate-age.html
Sounds like a new step in disease eradication. The BBC radio article said that they were using a "tobacco like plant". Let's hope they can make some other vaccines in cash crops (but not tobacco) that poor countries can grow and process themselves.
If it one is the solanaceae (https://en.m.wikipedia.org/wiki/Solanaceae) there might be scope.