Lysosomal-associated membrane protein 1 (LAMP-1) also known as lysosome-associated membrane glycoprotein 1 and CD107a (Cluster of Differentiation 107a), is a protein that in humans is encoded by the LAMP1 gene. The LAMP-1 glycoprotein is a type I transmembrane protein [PMID: 16973206] which is expressed at high or medium levels in at least 76 different normal tissue cell types. It resides primarily across lysosomal membranes [PMID: 2584229], and functions to provide selectins with carbohydrate ligands. LAMP-1 has also been shown to be a marker of degranulation on lymphocytes such as CD8+ and NK cells, and may also play a role in tumor cell differentiation and metastasis.