Heidelberg, Germany
July 8, 2008
Source:
Springer
The humble tomato could be a
suitable carrier for an oral vaccine against Alzheimer’s
disease, according to 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.
Although their research1, just published online in Springer’s
journal Biotechnology Letters, is still in the early stages, 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.
Kim and colleagues’ 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. The researchers 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.
They 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 team is currently
looking at strategies to increase the potency of the
tomato-based vaccine, because fresh tomatoes contain only 0.7%
protein and levels of foreign protein are even lower.
Reference
Transgenic tomatoes expressing human beta-amyloid for use as a
vaccine against Alzheimer’s disease
Youm JW, Jeon JH, Kim H, Kim YH, Ko K, Joung H, Kim HS (2008)
Biotechnology Letters (DOI 10.1007/s10529-008-9759-5).
This research was supported by the Plant Diversity Research
Center of the 21st Century Frontier R&D Program, Korea. |
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