Here, postmortem brain cerebral cortex tissue sections from AD patients carrying the ApoE4 allele and those from age-matched normal individuals were first costained with the lipid droplet surface protein perilipin 2 (PLIN2) and the microglial marker Iba-1, the neuronal marker NeuN, or the astrocyte marker GFAP. The gene discussed is APOE; the disease is Alzheimer disease.