Immunization with potato plants expressing VP60 protein protects against rabbit hemorrhagic disease virus

The major structural protein VP60 of rabbit hemorrhagic disease virus (RHDV ) has been produced in transgenic potato plants under the control of a caul iflower mosaic virus 35S promoter or a modified 35S promoter that included two copies of a strong transcriptional enhancer. Both types of promoters al lowed the production of specific mRNAs and detectable levels of recombinant VP60, which were higher for the constructs carrying the modified 35S promo ter. Rabbits immunized with leaf extracts from plants carrying this modifie d 35S promoter showed high anti-VP60 antibody titers and were fully protect ed against the hemorrhagic disease.