Several categories of proteins are targets for plant production systems, including food and feed additives, antibodies, industrial proteins, animal health products, and human pharmaceuticals. In this review, we will focus primarily on industrial proteins, antibodies, and animal and human health products - the majority of the past two years of work have been done in these areas. We will also discuss downstream processing and new technologies that have been added to the arsenal. We will conclude with some predictions for future direction. Vaccines Vaccines for human and animal disease prevention comprise the most competitive area for plant-based production of xenogenic proteins.
Traditional vaccines utilize either killed or attenuated whole disease-causing organisms.
Plant-based vaccines allow the use of selected subunits of the disease organism to generate an immune response in the host, avoiding the risk of causing the disease, as is possible with whole organisms. The greatest advantage of the plant system, how- ever, is the possibility of utilizing the plant material directly as a feed, thus generating an edible vaccine. Plant-based vaccines may be particularly useful for inducing immunity to disease organisms that colonize mucosal surfaces where large doses are needed to induce a strong IgA response. Several milestones must be met to create commercially valuable plant-produced vaccines. First, the plant must express the antigenic protein of choice.