There was prior research where they injected Amaloid Beta into mice with MS. it cured the mice of MS. I believe the plaques are a response, not the cause of alzheimers.
“Steinman warns that curing mice with an MS-like condition is just the first step on a long and potentially bumpy road to developing a therapy for people with the disease.”
http://www.newscientist.com/article/dn22128-alzheimers-villain-cures-multiple-sclerosis-in-mice.html