Stimulation with Aβ protofibrils induced a comparable response between AD and ND groups, independent of CMV serostatus and with a response pattern showing no increase in IFN-γ but strongly elevated levels of GM-CSF, IL-1β, IL-6, IL-8 and TNF-α suggesting that much of this reactivity could originate from antigen presenting cells such as monocytes. This evidence concerns the gene IL6 and Alzheimer disease.