CD107b, also known as LAMP-2, is a 105 kD, highly gylcosylated, type I transmembrane protein. CD107b is expressed in lysosomal/endosomal membranes in nearly all cells, and on the surface of activated platelets, activated lymphocytes and some tumor cell lines. LAMP-2 is known to have roles in cell adhesion and cellular homeostasis, including autophagocytosis and antigen presentation.