Alzheimer’s vaccine successful in mice

LONDON: A vaccine against Alzheimer’s is a step closer to reality after scientists succeeded in preventing the buildup of toxic brain proteins linked to the disease.

Experiments on mice showed the DNA vaccine, injected into skin, could delay the onset of Alzheimer’s with no serious side effects.

The findings, published in the journal Alzheimer’s Research and Therapy, could pave the way for clinical trials with human patients, the scientists said.

Two kinds of toxic protein or protein building blocks are thought to play a key role in Alzheimer’s — betaamyloid and tau.

Betaamyloid accumulates in sticky clumps in the brain and is a characteristic hallmark of the disease seen in patient postmortem examinations. Tau is a protein that produces destructive ‘‘tangles’’ within nerve cells. Some research suggests the two are linked, the betaamyloid promoting the formation of tau tangles.

The new vaccine contains DNA coding for a segment of the betaamyloid protein building block, or peptide.

In the study the vaccine trig gered an immune response that not only led to a 40% reduction in betaamyloid buildup, but also reduced tau formation by 50%.

The research was conducted on mice that were genetically engineered to develop a rodent equivalent of Alzheimer’s disease. Lead scientist Dr Roger Rosenberg, director of the Alzheimer’s Disease Centre at the University of Texas, said the study was ‘‘the culmination of a decade of research that has repeatedly demonstrated that this vaccine can effectively and safely target, in animal models, what we think may cause Alzheimer’s disease’’.

‘‘I believe we’re getting close to testing this therapy in people.’’