Plastid-Based Expression Strategies

Since the development of methodologies for achieving genetic modification of chloroplast genomes, termed transplastomic technologies, a straightforward use in the field of plant-based vaccines was initiated. Chloroplast transformation is mediated by homologous recombination that allows for site-specific insertion of foreign DNA into the plastome. This focus offers substantial advantages that include high yields, improved biosafety given by maternal inheritance in most plant species, and multigene expression through polycistrons allowing in theory for the straightforward production of multicomponent vaccines. One limitation of the system consists of the lack of glycosylation pathways, which are of relevance in some cases. State of the art in this area reflects a number of well-characterized vaccination models, although no one has passed clinical evaluations, which contrasts with other nuclear transient expression systems. Transplastomic technologies are envisioned as a relevant tool for developing new convenient vaccines