Potential potato cure

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Each year, about 350 million people worldwide are chronically infected with hepatitis B virus. Spread through blood and other bodily fluids, this virus puts them at high risk for cirrhosis, chronic liver disease and liver cancer -- diseases that kill about 1 million people each year. Yet through the magic of biotechnology, the lowly spud may change that.

For centuries, potatoes have saved lives with their nourishment. Now they'e tackling diseases spread by viruses and bacteria. Using potatoes with a protein gene (called antigens) from HBV spliced into them, researchers have produced high levels of immunity-providing antibodies in volunteers who ate them. Their findings, reported in the Proceedings of the National Academy of Sciences Online, should lead to cheaper, safer and easier-to-deliver vaccines.

In the study, scientists from Roswell Park Cancer Institute in Buffalo, N.Y., led by Dr. Yasmin Thanavala, fed volunteers small pieces of raw potato.

Some had "placebo potatoes," as it were; others received two doses of genetically engineered potatoes and one dose of placebos, while the third group ate only GE potatoes.

Nobody eating ordinary spuds developed extra hepatitis antibodies, while 53 percent of those who ate two doses of the GE ones did, as did more than 60 percent of the three-dose eaters. All recipients had previously received the HBV vaccine series, so the potatoes simply boosted an immunity they already had. Some people developed antigen levels 50 times higher after eating the super spuds.

That 60 percent level is still a far cry from the 90 percent to 95 percent protection rate provided by the three-dose series of HBV injections, but Dr. Thanavala is already working to improve the potatoes' immunogenicity to that level and in a single dose. One method comprises inserting more of the viral antigen into the potato. Another would insert a harmless bacterium into the potato as an adjuvant, an immune-system stimulator that helps produce more antibodies.

Current HBV vaccines aren't particularly expensive to produce; the real costs come from the need for refrigeration, injection by a trained person, and using a fresh needle and syringe each time: No small potatoes considering some studies have shown clinically reused needles and syringes may do far more to spread HIV/AIDS in Africa than is reported, since politically correct health officials wish to focus on vaginal sex.

Formerly, "edible vaccine" meant consuming vaccine foods directly. But worries over medicinal strains getting mixed in with normal food put the kibosh on that. So "edible vaccines" wouldn't really be eaten, notes Dr. Thanavala. Rather, they probably would be powdered and ingested in gel capsules.

Successful potato-vaccine experiments aren't new. Charles Arntzen of the Biodesign Institute at Arizona State University has induced antibodies in humans to both the diarrhea-causing Norwalk virus and the dreaded E. coli. But these pathogens attack the stomach. Dr. Thanavala's antigens had to make it past the stomach and into the bloodstream. That's what makes the process so promising against so many diseases.

"I'm bowled over each time this works as well as it does," she told me. "We've shown the antigen in plants is encapsulated in membranes, and we believe this allows it to survive stomach conditions until reaches the small intestine." As such, she has given the entire field of plant-based vaccines a boost -- and a large field it is. At least 45 different antigens have been produced in a wide variety of plants to treat diseases affecting billions of people.

A short list includes an HBV vaccine being grown in lettuce, a rabies vaccine in spinach and tobacco, and an anthrax vaccine in tobacco and lettuce. Texas-based ProdiGene is developing a corn-based HIV vaccine. You probably don't know what hepatitis E is, but somebody is using tomatoes to make a vaccine against it.

Dr. Thanavala wouldn't speculate when a potato-based vaccine might be available. She wants to keep it in the lab until it meets all her goals. But remember the axiom: "Perfection is the enemy of the good." People are dying now and this vaccine could get regulatory approval in just a few years.

It sounds like a cause for the Bill and Melinda Gates Foundation. Are you listening, guys?

Michael Fumento is author of "BioEvolution: How Biotechnology Is Changing Our World." He is a Hudson Institute senior fellow and a columnist for Scripps Howard News Service.