GPNMB and Alzheimer disease: GPNMB+ microglia, a recently identified subtype, are elevated in the frontal white matter and cortex of patients with AD.[67] Additionally, GPNMB is expressed in activated microglia[68] and is associated with AD pathology.[22] Furthermore, the expression of GPNMB in microglia is correlated with recently reported subtypes, such as disease-associated microglia (DAM)[63] and microglial neurodegenerative phenotype (MGnD),[69] which are closely associated with plaques and neurodegeneration.