Major Step Toward an
Alzheimer's Vaccine
A team of researchers from Université Laval,
CHU de Québec, and pharmaceutical firm GlaxoSmithKline (GSK) has discovered a
way to stimulate the brain's natural defense mechanisms in people with
Alzheimer's disease. This major breakthrough, details of which are presented
January 15 in an early online edition of the Proceedings of the
National Academy of Sciences (PNAS), opens the door to the
development of a treatment for Alzheimer's disease and a vaccine to prevent the
illness.
One
of the main characteristics of Alzheimer's disease is the production in the brain
of a toxic molecule known as amyloid beta. Microglial cells, the nervous
system's defenders, are unable to eliminate this substance, which forms
deposits called senile plaques.
The
team led by Dr. Serge Rivest, professor at Université Laval's Faculty of
Medicine and researcher at the CHU de Québec research center, identified a
molecule that stimulates the activity of the brain's immune cells. The
molecule, known as MPL (monophosphoryl lipid A), has been used extensively as a
vaccine adjuvant by GSK for many years, and its safety is well established.
In mice with Alzheimer's symptoms, weekly injections of MPL over a twelve-week period eliminated up to 80% of senile plaques. In addition, tests measuring the mice's ability to learn new tasks showed significant improvement in cognitive function over the same period.
The
researchers see two potential uses for MPL. It could be administered by
intramuscular injection to people with Alzheimer's disease to slow the
progression of the illness. It could also be incorporated into a vaccine
designed to stimulate the production of antibodies against amyloid beta.
"The vaccine could be given to people who already have the disease to
stimulate their natural immunity," said Serge Rivest. "It could also
be administered as a preventive measure to people with risk factors for
Alzheimer's disease."
"When
our team started working on Alzheimer's disease a decade ago, our goal was to
develop better treatment for Alzheimer's patients," explained Professor
Rivest. "With the discovery announced today, I think we're close to our
objective."
Story Source:
The
above story is reprinted from materials provided byUniversité
Laval, via EurekAlert!, a
service of AAAS.
Note: Materials may be edited for content and length. For further
information, please contact the source cited above.
Journal Reference:
1. Jean-Philippe Michaud, Maxime Hallé, Antoine
Lampron, Peter Thériault, Paul Préfontaine, Mohammed Filali, Pascale
Tribout-Jover, Anne-Marie Lanteigne, Rachel Jodoin, Christopher Cluff, Vincent
Brichard, Rémi Palmantier, Anthony Pilorget, Daniel Larocque, and Serge
Rivest. Toll-like receptor 4 stimulation with the detoxified ligand
monophosphoryl lipid A improves Alzheimer’s disease-related pathology. PNAS,
January 15, 2013 DOI: 10.1073/pnas.1215165110