APOE and Alzheimer disease: We examined how glial activation and pathological burden differ between the olfactory cortex (OC) and olfactory bulb (OB) across disease stages.<h4>Methods</h4>Post mortem OC and OB samples from cognitively normal (CN), mild cognitive impairment, and AD cases were analyzed using immunohistochemistry and immunofluorescence for amyloid beta (Aβ), phosphorylated tau (pTau), Iba1 (microglia), GFAP (astrocyte), and apolipoprotein E (apoE).<h4>Results</h4>Both regions showed stage-dependent increases in Aβ and pTau, with regionally distinct glial responses.