One of the characteristic hallmarks of Alzheimer’s disease (AD) is the buildup of amyloid-beta plaques in the brain. Most therapies designed to treat AD target these plaques, but they’ve largely failed in clinical trials. New research by Salk scientists upends conventional views of the origin of one prevalent type of plaque, indicating a reason why treatments have been unsuccessful.
The traditional view holds that the brain’s trash-clearing immune cells, called microglia, inhibit the growth of plaques by “eating” them. The Salk scientists show instead that microglia promote the formation of dense-core plaques, and that this action sweeps wispy plaque material away from neurons, where it causes cell death. The research, which was published in Nature Immunology on April 15, 2021, suggests that dense-core plaques play a protective role, so treatments to destroy them may do more harm…