The green revolution: plants as heterologous expression vectors.

Agrobacterium tumefaciens mediated gene transfer into the plant genome laid the groundwork for new procedures aimed at crop improvement, including resistance to pathogens, increased product yield, modified oil content, and resistance to environmental stress conditions. New developments in molecular plant virology have led to the generation of plant-based systems for transient expression of foreign sequences using plant virus vectors. In the last decade both transgenic plants and plant virus vectors have been used increasingly to produce a wide range of biomedical reagents, including vaccine antigens, in a safe and economically feasible manner. These new plant-based technologies have enormous potential for a variety of applications, including the oral delivery of vaccine antigens.