GFAP and Alzheimer disease: High-resolution MS combined with tandem mass-tags-based multiplexing and immunodepletion techniques applied to 5 control and 5 AD patient samples identified 139 out of 2327 differentially expressed proteins, including t-tau, neuronal pentraxin-2 (NPTX2), GFAP, neuronal cell adhesion molecule-1 (NCAM1), pyruvate kinase M (PKM), and tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein gamma (YWHAG).