Oral Alzheimer's Vaccine Promising
Effective in mice and appears safer than previous vaccines
10/26/2004 3:36 PM
A new oral vaccine for Alzheimer's disease has prevented plaque deposits in mouse brains and appears to be safer than previous vaccines.
Hideo Hara and colleagues from Japan's National Institute for Longevity Sciences and Brigham and Women's Hospital in Boston, Massachusetts in the US report that the oral vaccine effectively reduces Alzheimer's disease pathology.
"This new therapy seems to be effective for prevention and treatment of Alzheimer's disease," writes Hara.
Amyloid antibodies
Alzheimer's disease is linked with deposits of amyloid-beta protein in the central nervous system.
By increasing the production of antibodies targeting amyloid-beta, the immune system can be harnessed to reduce the deposits.
In an earlier vaccine study taking this approach, however, subjects developed acute meningoencephalitis-inflammation of the brain-likely caused by an autoimmune reaction involving T cells. This led to the trial being halted.
The oral vaccine aims to minimize T cell activation to provide a safer treatment.
Safer treatment
The vaccine was created through the attachment of amyloid-beta DNA to an adeno-associated virus. The viral vector is administered orally.
In mice, the researchers report, the vaccine decreased amyloid-beta levels and there was a significantly reduced T cell immune response. A single dose enhanced the production of amyloid-beta antibodies for more than six months.
Additionally, examination of mouse brain tissue showed that amyloid deposits were decreased compared to non-treated mice.
The research is reported in the Journal of Alzheimer's Disease.