The study suggests a powerful and complex connection between Alzheimer’s and one of the most common viruses. The finding was published Wednesday in the journal Science Advances.
Herpes simplex virus type 1 (HSV-1) is the common type of herpes that causes cold sores on your mouth. The World Health Organization estimates that 67% of the population under 50 carry HSV-1.
In 3D models of human brains, scientists found that HSV-1 can trigger buildup that resembles amyloid plaques. These are sticky clumps of proteins that tend to accumulate between the neurons of Alzheimer’s disease patients.
A working hypothesis is that the virus triggers an immune response in the brain, causing it to create those plaques in order to “trap” the virus.
David Kaplan. the study’s senior author and director of Tufts University’s Tissue Engineering and Research Center, said, “While the initial formation of amyloid-beta is beneficial for clearing infection, over time, these proteins aggregate to form plaques which themselves eventually become toxic to cells of the brain.”