Washington, July 9 : Besides making pasta's curry tangy, the plump and red tomato has far more serious benefits - the humble fruit can be a suitable carrier for an oral vaccine against Alzheimer's disease, says a group of researchers.
The study, conducted by HyunSoon Kim from the Korea Research Institute of Bioscience and Biotechnology (KRIBB) in Korea and colleagues from Digital Biotech Inc. and the Department of Biological Science at Wonkwang University, is currently in the early stages.
However, it is a promising first step towards finding an edible vaccine against the neurodegenerative disease.
Alzheimer's disease is the most common cause of dementia and it progresses over a long period of time.
It is thought to be caused by the accumulation of human beta-amyloid, a toxic insoluble fibrous protein in the brain, which leads to the death of neurons.
Reducing the accumulation of beta-amyloid may inhibit the degeneration of the nervous system and therefore prevent or delay the onset of Alzheimer's disease. One approach is to stimulate the immune system to reduce beta-amyloid in the brain.
In the study, the researchers' aim was to develop a plant-derived vaccine against Alzheimer's disease, since beta-amyloid is toxic to animal cells.
Tomatoes are an attractive candidate as a vaccine carrier because they can be eaten without heat treatment, which reduces the risk of destroying the immune stimulation potential of the foreign protein.
In the study, the scientists inserted the beta-amyloid gene into the tomato genome and measured the immune responses to the tomato-derived toxic protein in a group of 15-month-old mice. hey immunized the mice orally with the transgenic tomato plants once a week for three weeks, and also gave the mice a booster seven weeks after the first tomato feed. Blood analyses showed a strong immune response after the booster, with the production of antibodies to the human foreign protein.
The authors conclude: "Although we did not reveal a reduction of existing plaques in the brain of mice challenged with tomato-derived beta-amyloid...this study represents a unique approach in which transgenic plants expressing beta-amyloid protein are used to produce a vaccine."
The study is published online in Springer's journal Biotechnology Letters.