When Alzheimer’s disease occurs, the brain undergoes different types of damage. Among them, the abnormal accumulation outside nerve cells of a protein called ß-amyloid peptide leading to the formation of plaques. These are deposited between nerve cells located in the gray matter of the cerebral cortex, causing a dysfunction of the connections between neurons. “, specifies the Alzheimer Research Foundation.
Counteract the formation of plaques
One of the research challenges therefore lies in countering the formation of these plaques. In a study published April 3 in Science Translational Medicinescientists from Washington University in St. Louis believe they have found a way to eliminate harmful plaques by directly mobilizing immune cells.
The very principle of immunotherapy.
They showed that the activation of certain immune cells called microglia reduces amyloid plaques in the brain and attenuates behavioral abnormalities in mice suffering from a form of Alzheimer’s disease.
Circumvent the action of a protein
Typically, microglia surround plaques to create a barrier that controls the spread of harmful proteins. They can also engulf and destroy plaque proteins.
But this is not the case in Alzheimer’s disease. “ The Source of their passivity could come from a protein called APOE which is a component of amyloid plaques », Explain the authors. “ These APOE proteins bind to a receptor – LILRB4 – on microglia », preventing them from carrying out their mission.
The scientists therefore administered a “homemade” antibody that prevented APOE from binding to LILRB4. They then observed that the microglia thus activated were capable of eliminating beta amyloid plaques.
Hope for other neurodegenerative diseases
According to the authors, this approach could have implications beyond Alzheimer’s disease. Toxic brain protein clumps are characteristic of many neurodegenerative diseases, including Parkinson’s disease, amyotrophic lateral sclerosis (ALS), and Huntington’s disease.
Source : Science Translational Medicine
