A new vaccine that targets inflamed brain cells associated with Alzheimer’s disease could eventually prevent or modify the course of the disease, according to a new study, yet to be peer-reviewed. The vaccine appeared to reduce inflammation and other biomarkers in the brains of mice with the illness, also improving their awareness.

Alzheimer’s is a progressive brain disorder characterized by a gradual deterioration of brain function, resulting in the accumulation of specific protein deposits. This leads to brain shrinkage and the loss of brain cells. As the most prevalent cause of dementia, it leads to a decline in memory, cognitive abilities, behavior, and social skills.

The vaccine was developed by scientists from Juntendo University in Japan. It works by training the immune system to target senescent brain cells — damaged cells in the body that don’t die when they should and have been linked to aging. A study last year found that people with Alzheimer’s have more of these cells than those without the disease.

“Alzheimer’s disease now accounts for 50% to 70% of dementia patients worldwide. Our study’s novel vaccine test in mice points to a potential way to prevent or modify the disease. The future challenge will be to achieve similar results in humans,” Chieh-Lun Hsiao, a postdoctoral fellow and the study lead author, said in a press release.

Tackling Alzheimer’s disease

The researchers tested their new vaccine on mice bred to have brains that deteriorate just like humans who have Alzheimer’s. The damage is caused by the accumulation of amyloid-beta — a protein. The mice were divided into two groups. Only one was given the actual vaccine, reporting signs of reduced inflammation and fewer amyloid deposits.

The mice that received the vaccine also seemed to act more like typical mice when compared to those in the control group. They also continued to have anxiety as they aged, which is not the case for people with late-stage Alzheimer’s, and were more aware of their surroundings during maze tests, which suggests a lessening of the disease symptoms.

“Earlier studies using different vaccines to treat Alzheimer’s disease in mouse models have been successful in reducing amyloid plaque deposits and inflammatory factors. However, what makes our study different is that our vaccine also altered the behavior of these mice for the better,” Chieh-Lun Hsiao said in a press release.

The study was presented at the American Heart Association’s Basic Cardiovascular Sciences Scientific Sessions 2023. Once formally peer-reviewed, further research will be needed to validate the findings and to test the vaccine’s safety. This suggests there’s likely still a long way to go before large-scale trials can even start to be discussed.

However, there has been some good news lately in Alzheimer’s treatment, with other experimental candidates in clinical trials. A new drug was found to delay progression of the disease by up to 35%, with patients having their decline slow down by up to 7.5 months. These new developments could one day be a game changer for the disease.