The Q38-480 monoclonal antibody specifically binds to mouse CD150, also known as SLAM (signaling lymphocyte activation molecule). CD150 is a type 1 transmembrane glycoprotein that is a member of the CD2 subfamily of the Ig superfamily. It is encoded by the Slamf1 (signaling lymphocytic activation molecule family member 1) gene. CD150 is differentially expressed on subsets of thymocytes, T and B lymphocytes, dendritic cells, macrophages, and endothelial cells. SLAM plays multiple roles in innate and adaptive immunity serving as an adhesion molecule and/or coreceptor. CD150-mediated costimulation of TCR-activated T cells reportedly results in the increased production of IFN-γ by Th1 cells and is required for IL-4 production by T follicular helper cells. CD150 also plays important roles in hematopoietic cell developmental pathways. CD150 is differentially expressed by self-renewing adult hematopoietic stem cells (HSC) whereas non-multipotent hematopoietic progenitor cells are CD150-. Utilizing additional cell surface markers, lineage-negative CD150+CD48-CD41- cell fractions are reported to be highly enriched for adult HSC.