The mouse monoclonal antibody SY11B5 recognizes CD157, an approximately 45 kDa GPI-anchored extracellular protein expressed mainly on monocytes, macrophages, granulocytes and bone marrow stromal cells.
Bone marrow stromal cell antigen 1,CD157 (cADPr hydrolase 2) is a GPI-anchored ectoenzyme possessing ADP-ribosyl cyclase and cyclic ADP-ribose hydrolase activity. It uses NAD and cADP-ribose as substrates. CD157 is expressed on granulocytes, monocytes, macrophages, follicular dendritic cells, bone marrow stromal cells and human umbilical cord vein endothelial cells. In case of rheumatoid arthritis is expression is often higher and it is also differentially expressed in the myeloid leukemias. It may also have a signaling role.,BST1, cADPr hydrolase 2