Project Summary: The project is a drug discovery project in Alzheimer's disease from assay design to hit confirmation at the LDDN. The aim is to optimize a screen based on CD33 cell surface expression. Indeed it has been discovered that CD33, a protein expressed in monocytes, is involved in Alzheimer's disease by decrease monocytes ability to uptake amyloid beta. Indeed people having a specific SNP in CD33 (protective allele) that decrease CD33 cell surface expression show a lower risk of developing AD. The aim of the screen is to find small compounds among a bioactive compound library that will decrease CD33 cell surface expression in order to better understand the pathway involved and maybe develop a drug.