Ask the average person about how plants contribute to health, and you'll probably get two responses - firstly, a mention of the nutritional value of fruit and veg, and secondly, a vague memory of the role of plant compounds as medicines.
But could plants also help deliver vaccines? Would staying healthy be easier if, rather than getting a vaccine through a jab in the arm, you simply ate a banana, a potato, or a tomato?
Getting vaccines out across the world and administering them safely can be a difficult business. Researchers searching for an easier and affordable means of immunization had the idea of using fruit and vegetable plants as factories for synthesizing vaccines, known as ‘‘edible vaccines’’.
An article by researchers Monika Sharma and Bhumika Soods describes edible vaccines as follows: "Invented by Charles J. Arntzen (Biodesign institute, Arizona State University) these subunit vaccines are made up of antigens that can be grown in genetically modified plants and delivered through the edible parts of the plant (Arntzen 1997). They do not contain the genes responsible for pathogenesis, making them safe as they can generate an immune response in the body without causing disease. Edible vaccines are likely to
overcome the hurdles posed by traditional vaccines, as they can be delivered without needles, do not require refrigeration and can be made, less expensively, right in the area in which they will be delivered."
But, as the researchers state, getting ideas from the lab to the real world is not a straight-forward journey: "Though the road ahead seems promising, there are several constraints which restrict the success and public acceptability of these vaccines. These include problems of choice of plants, storage, delivery, dosage, safety, public perception, quality control and licensing."
What do you think? Would you want to see vegetables that can deliver vaccines into your body.
Richard P Grant blogs on the question here: http://blog.the-scientist.com/2011/03/15/a-banana-a-day/