CD33 is a sialic acid-binding receptor, within the sialic-acid-binding immunoglobulin-type lectin (SIGLEC) family, known to bind sialylated glycans, and plays an important role in microglia activation (Estus et al., 2019), highlighting the potential implication of glycosylation and sialylation in AD and other neurodegenerative disorders. Here, CD33 is linked to Alzheimer disease.