BACE1 and Alzheimer disease: They notably demonstrated that BACE-1, soluble amyloid precursor protein (sAPP)β, multiple complement proteins and the inflammatory cytokines IL-6, TNF-α, and IL-1β were significantly higher in astrocyte-derived exosomes from patients with AD than controls, while Aβ42, GDNF, septin-8, and complement regulatory proteins were downregulated (Goetzl et al., 2016b,2018).