The extracted BDE proteins that have no change in AD were Aβ42, APP, sAPPα, sAPPβ, BACE-1, Aβ42/p-T181-tau, γ-secretase, t-tau, p-T181-tau, p-S396-tau, p-T181-tau/t-tau, t-tau/Aβ42, N-224 tau, N-123 tau, MR tau, FL tau, cathepsin D, LAMP-1, t-IRS-1, p-Y-IRS-1, p-S312-IRS-1, p-S312-IRS-1/p-Y-IRS-1, IL-6, HSP70, ubiquitinylated protein, GluSyn, NF-Lch, NS-enolase, CD81, TSG101, and Septin-8. Here, CTSD is linked to Alzheimer disease.