University of Toronto researchers develop potent vaccine for A...( Researchers in the University of Toro...),Health

Researchers in the University of Toronto's Faculty of Medicine have discovered that a vaccine may help prevent and treat the disabling memory loss and cognitive impairment (dementia) of Alzheimer's disease.

Alzheimer's occurs when toxic biochemical compounds known as amyloid peptides accumulate in the brain, forming amyloid plaque deposits and injuring nerve cells, eventually causing dementia. While previous studies have shown that vaccinating transgenic mice with this peptide could remove the amyloid plaques, there was never any evidence of improvement in brain function.

After developing transgenic mice with amyloid plaques and cognitive impairment similar to those found in human Alzheimer's, scientists at U of T's Centre for Research in Neurodegenerative Diseases (CRND) determined that immunization with amyloid peptides blocked both the production of the plaques and learning impairment.

"Not only were we able to clean up the brain tissue, but we also prevented the behavioural consequences of Alzheimer's," says Dr. Peter St George-Hyslop, director of the CRND and a neurologist at the University Health Network. "Obviously, it is more important that a treatment or prevention in humans be able to block the clinical dementia." St George-Hyslop and his colleagues say the amyloid peptide vaccination is ready to be tested on humans. "Our results also show that pharmaceutical treatments that are directed at blocking the formation of the peptide or that accelerate its removal might also be good ways to treat Alzheimer's either alone or in conjunction with other interventions like vaccination," says Christopher Janus, research associate at the CRND and the study's first author. "In the future there might be a cocktail of treatments including drugs which block formation and inhibit the toxicity and then a vaccination which will remove the plaque."

The researchers believe this study provides the final element of proof that Alzheimer's is i
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Contact: Steven de Sousa
steven.desousa@utoronto.ca
416-978-5949
University of Toronto
19-Dec-2000