Up to 12 percent of Americans may get Alzheimer's disease, current statistics say.  In the quest to prevent Alzheimer's, or at least make it manageable like diabetes, a group of researchers are working on a nasally-delivered vaccine that promises to protect against Alzheimer's.  Bonus: It may help prevent strokes also.

The new vaccine repairs vascular damage in the brain by using the body's own immune system and, in addition to its prophylactic effect, it can work even when Alzheimer's symptoms are already present, according to the paper in Neurobiology of Aging.

"Using part of a drug that was previously tested as an influenza drug, we've managed to successfully induce an immune response against amyloid proteins in the blood vessels," says Dr. Dan Frenkel of Tel Aviv University's Department of Neurobiology, who collaborated on the project with Prof. Howard L. Weiner of Brigham and Women's Hospital, Harvard Medical School. "In early pre-clinical studies, we've found it can prevent both brain tissue damage and restore cognitive impairment," he adds.

Modifying a vaccine technology owned by Glaxo Smith Kline, their approach activates a natural mechanism in our bodies that fights against vascular damage in the brain.   The vaccine activates macrophages, large proteins in the body that swallow foreign antigens, and they clear away the damaging build-up of waxy amyloid proteins in our brain's vascular system.   Animal models showed that once these proteins are cleared from the brain, further damage can be prevented, and existing damage due to a previous stroke can be repaired. 

An Alzheimer's cure?

Ignoring the media hype that results around a lot of experiments done in animal models, could it be a vaccine and a cure for Alzheimer's disease? "It appears that this could be the case," says Frenkel. "We've found a way to use the immune response stimulated by this drug to prevent hemorrhagic strokes which lead to permanent brain damage."

In the animal models in mice, they did MRIs and the used "object recognition" experiments, testing the cognitive functions both before and after administration of the vaccine. MRI screenings confirmed that, after the vaccine was administered, further vascular damage was prevented, and the object recognition experiments indicated that those animals treated with the new vaccine returned to normal behavior. 

Frenkel believes that this approach, when applied to a human test population, will be able to prevent the downward health spiral of Alzheimer's and dementia. The vaccine could be given to people who are at risk, those who show very early symptoms of these diseases, and those who have already suffered strokes to repair any vascular damage. 

So far the vaccine has shown no signs of toxicity in animal models and Frenkel is hopeful that this new approach could lead to a cure, or at least an effective treatment, for the vascular dementia found in 80% of all people with Alzheimer's.