APOC3 and Alzheimer disease: Furthermore, five circulating EV proteins, including apolipoprotein C-III, beta-2-glycoprotein 1, C4b-binding protein alpha chain (C4BPα), complement C3, and immunoglobulin kappa variable 2–30 are significantly down-regulated in AD patients compared with control individuals, implying these proteins as putative biomarker candidates.