A brain scan showing the degenerative effects of Alzheimer's disease. The black areas show the affected areas of the brain (TOI Photo)

Is an Alzheimer's vaccine close at hand?

A vaccine designed to combat a protein implicated in Alzheimer's disease has proven effective in mice, US scientists say.

Abnormal tau protein accumulates into damaging tangles in the memory centre of the brains of Alzheimer's patients, noted a team at the New York University Medical Centre (NYUMC).

However, the new NYUMC-developed vaccine prevented tau tangles in several regions of the central nervous system of mice that were genetically engineered to produce abnormal tau proteins. The vaccine prompted the immune system to produce antibodies that could enter the brain and bind to abnormal tau, the researchers said. This prevented tau from forming harmful tangles and causing motor coordination problems in the mice.

The study, which is published in the Aug. 22 issue of the Journal of Neuroscience, is the first to show that a vaccine can induce the immune system to combat abnormal tau protein.

"This approach may have extensive therapeutic implications, because you can specifically target the problematic protein," team leader Einar Sigurdsson, assistant professor of psychiatry and pathology, said in a prepared statement.

"Tau aggregates are inside the cell, making it especially difficult to develop a therapy to target and clear them from the cell," Sigurdsson noted.