http://www.newsweek.com/scientists-how-alzheimers-disease-spreads-through-brain-and-how-we-can-stop-978154

Scientists believe that buildup of a brain protein called amyloid beta is the root of Alzheimer’s disease, but exactly how this disease spreads throughout the brain remains unclear. Now, new research believes it may have found the answer, suggesting that a cell part previously thought to play a role in waste removal is actually the key to the spread of Alzheimer’s in the brain.

The study, published online in Acta Neuropathologica, used brain samples from deceased patients with Alzheimer’s disease and controls who died with a healthy brain. They looked specifically at parts of the cell called exosomes. These cell parts are small membrane covered droplets that help to remove cell waste products, a press release reported. However, closer examination revealed the cell part may also play an important part in Alzheimer’s disease ability to spread throughout the brain.