The significance of the successfully developed GM food vaccine

New Scientist

14.02.2005

By Andy Coghlan

Genetically engineered potatoes containing a hepatitis B vaccine have successfully boosted immunity in their first human trials.

But the newly-published study missed a moving target - drug developers are now abandoning their quest for vaccines contained in staple foods like bananas, tomatoes or potatoes.

developers have changed tack to avoid any possibility of vaccine-laden food straying into shops or markets. If this occurred, it could be unwittingly eaten by consumers, with unpredictable results.

Instead, developers are now focusing on making vaccines in the safely edible leaves of plants not on sale as food.

“We’ve not worked with potatoes for two years now,” says Charles Arntzen at Arizona State University in Tempe, US, who led the potato study and is a veteran of the decade-long bid to produce GM vaccines in foods. “We don’t say ‘edible’ vaccine any more - we say ‘heat-stable oral vaccines’.”

Despite abandoning the potatoes, Arntzen says he is proud of the results, and that they support the principle of oral vaccination.

In the study, the volunteers all ate finely-chopped chunks of raw potato. Some ate potatoes in which a major surface protein of the hepatitis B virus had been produced, while others received unaltered potatoes.

More than 60% of the volunteers who had three doses of the vaccine made a large number of extra antibodies against the viral protein, as did 53% on two doses. None of the volunteers eating ordinary potato generated new antibodies.

“We are very interested in the approach, and these results are very encouraging,” says Martin Friede at the World Health Organization’s Initiative for Vaccine Research.

Daily Mail

By Lucy Elkins

11.05.2009

Why are so many adults suddenly getting allergies?

An allergy occurs when the body over-reacts to the presence of something harmless and produces antibodies and chemicals such as histamine in response.

It is the body’s way of trying to get rid of the perceived invader as rapidly as possible.

Typically, allergies start in childhood, when the immature immune system is more likely to over-react, but often improve in time. So why are adults now being affected for the first time?

‘No one truly understands what prompts allergies in later life,’ says Isobel Skypala, a specialist allergy dietician at London’s Royal Brompton Hospital.

‘Hormonal fluctuations also have an effect on the severity of allergies’

‘In the case of food allergies, it may be partly due to the wide range of foods available these days. But we are also seeing more severe reactions in adults to plant foods that have long been part of the UK diet, such as lettuce,’ she says.

Adults who already have an allergy are also increasingly developing further allergies (’multiple allergies’).