The clone FR4D11, a mouse monoclonal antibody recognizes a 100 kDa protein that has neutral metalloendopeptidase activity and inactivates a variety of biologically active peptides known as CD10. It is also known as common acute lymphoblastic leukemia antigen (CALLA). CD10 is a type II cell surface glycoprotein typically expressed on acute lymphoblastic leukemias (ALL). Normal, healthy precursors of B and T cells and granulocytes also express CD10. CD10 plays important role in the development process of B cells the in germinal center.