Lipidomic analyses of microglial CD11b-positive small extracellular vesicles from the cryopreserved parietal cortex of a restricted number of patients and controls indicated not only increased levels of TREM2, but also a proinflammatory lipid profile in AD (e.g., increase in the most abundant monohexosylceramide d18:1/24:1 [430]). Here, TREM2 is linked to Alzheimer disease.