S100B and Alzheimer disease: In addition to the core CSF AD-biomarkers, some of the most promising novel CSF biomarkers are related to neurodegeneration and microglial or astroglial activation, specifically soluble triggering receptor expressed on myeloid cells 2 (sTREM2), glial fibrillary acidic protein and YKL-40 (also known as chitinase 3-protein 1) as well as S100 calcium-binding protein B (S100b).