CD44 and Alzheimer disease: Distinct from hematopoietic stem cells (based on CD45+, CD117+) and endothelial progenitor cells (based on CD45−, CD34+, Flk−1+), large multi-nucleated AD-CMG progenitors displayed the following profile: CD45−/CD29+/Sca1−/CD44+/CD81+/CD133+/CD31−/CD34−/CD73−/CD90−/CD117−/Flk1−/CMH1−/CMH2−.