GAS6 and Alzheimer disease: Thus, to address this important issue, in the present study, we assessed whether baseline sTREM2 as well as AXL, MERTK, GAS6, LPL, CST7, SPP1 and CSF1 concentrations are associated with future amyloid and tau accumulation and cognitive decline over several years in nondemented individuals at risk for AD due to the presence of amyloid- or tau-PET pathologies.