The antibody reacts with CD38 antigen, a 45 kDa integral membrane glycoprotein expressed on all pre-B cells, plasma cells, thymocytes, activated T cells , NK cells, monocyte/macrophages and dentritic cells. CD38 antigen is expressed 90% of CD34+ cells, but not on pluripotent stem cells. Coexpression of CD38 + and CD34+ indicates lineage commitment of those cells. CD38 antigen acts as an ectoenzyme capable of catalysing multipe reactions and play role on regulator of cell activation and proleferation depending on cellular enviroment. Application : Leukemia phenotyping and classification; monitoring of HIV-1 infection and progression.