Plant-based vaccines: Expression and oral immunogenicity

The use of plants for production and delivery of vaccine proteins has shown promise in research conducted during the past decade. Genes encoding bacterial and viral antigens are faithfully expressed, processed, and assembled in plant cells to form immunogenic proteins. Studies in animals and humans showed that ingestion of transgenic potato containing vaccine proteins caused production of antigen-specific antibodies in serum and mucosal secretions. Future studies must aim to improve antigen expression and to develop processes to formulate plant material for antigen stability and convenient oral delivery. Furthermore, production methods should ensure the containment of pharmaceutical crops and prevent contamination of the food supply.