The application of plant-based systems to produce biopharmaceuticals for human and veterinary indications is a rapidly expanding field. Available systems range from stable transgenic root-cell culture to transient expression in whole plants. Products that have been expressed include monoclonal antibodies (MAbs) (1), subunit vaccines (2), virus-like particles (VLPs) (3), specialty enzymes (4), and structural proteins such as collagen (5). “Traditional” bioproduction platforms such as Chinese hamster ovary (CHO) cells, Escherichia coli, and Pichia pastoris have long histories of patient safety…