CD9 and Alzheimer disease: To further characterize the association of Aβ with EVs, we examined EVs released from cultured human neurons derived from induced pluripotent stem cells generated from fibroblasts taken from a patient with AD caused by a PS1 mutation (hNPS1A246E neurons) and control neurons generated from fibroblasts from a neurologically normal human subject.33 EVs isolated from culture medium were evaluated by NTA and immunoblotting with antibodies against the EV markers flotillin-1 and CD9 (Supplementary Figure 1).