CD81 normalized levels of Aβ42 (8.64 ± 6.037 pg/mL vs 5.40 ± 1.700 pg/mL, P < 0.05), P‐T181‐tau (34.68 ± 15.198 pg/mL vs 26.68 ± 9.816 pg/mL, P < 0.05), and MMP‐9 (4.11 ± 3.006 ng/mL vs 1.60 ± 1.078 ng/mL, P < 0.01) in plasma NDEVs were elevated in patients with AD as compared with NCs (Fig. 3B,D,F). The gene discussed is MMP9; the disease is Alzheimer disease.