Delivering Meds with Dinner

If an adventurous band of plant biologists have their way, the world's children — and their needle-phobic parents — will someday get their vaccine inoculations with dinner rather than from a sharp stick in the arm.

Vaccines protect by introducing a substance called an antigen into your body. The antigen — a live or killed microbe particle — provokes an immune response in which you make antibodies to fight the antigen. This reaction inoculates you by teaching your body how to fight a specific infectious agent, such as the flu virus. If you're exposed later on, you're ready to beat the bug.

Most modern vaccines are injected. Some, like the polio vaccine, may be delivered on a sugar cube. Others can be inhaled. But for 15 years, Charles Arntzen, founder of Arizona State University's Biodesign Institute at Arizona State University, and his fellows across the country have been working toward creating "edible vaccines" — vaccines created via genetic engineering, by inserting the antigen, a viral gene, into food.

Not just any food, mind you. Heat destroys vaccines, so to get the benefits, you'd have to eat the food raw. To date, researchers have concentrated on potatoes, tomatoes, and bananas, with the emphasis on the latter two because — let's face it — raw potatoes are no treat.

The primary target for the vaccines is diarrheal disease such as cholera and E. coli, which kill more than 2.5 million children under the age of 5 every year. Other possibilities include the Norwalk virus that's played havoc with cruise liner vacations, hepatitis B, and HIV, the virus that causes AIDS.

In trials with cows, mice, rabbits, and mink, antigen-containing tobacco leaves, alfalfa, tomatoes, and lettuce leaves have been able to trigger immune reactions to diseases as varied as anthrax and the common cold. In a handful of FDA-approved human studies at the National Vaccine Testing Center, the University of Maryland, and Roswell Park Cancer Centre in Buffalo, New York, human volunteers who ate about 100 grams (3.5 ounces) of raw potatoes containing anti-diarrheal or hepatitis vaccines showed an immune response similar to what you might expect from an injected vaccine.

Most researchers expect edible vaccines for animals to show up before edible vaccines for human beings. When the human versions do arrive, the plant scientists say they'll be cheap, administered without a needle and without a doctor.

Just don't expect to toss some seeds in the window box and grow your own. For one thing, fresh food has a relatively short shelf life. You can't stick your vaccine-laden banana in the fridge and use it sometime in the next six months. Second, unless the food is grown in controlled conditions, you can't be sure it has the correct amount of protective antigen. Finally, nobody wants these genetically modified foods to somehow slip into the general food supply.

In the end, the plant guys say, the banana, tomato, potato, or other vaccine-toting food will probably be sliced and diced, frozen, or ground to powder and pressed into chips or tucked into a pill to make a stable med that can be produced with basic agricultural and food-processing technologies available virtually anywhere around the globe.

No needles, no doctors, no fuss. Now that's a med any mother could love.

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