CD68 (also known as LAMP4 or SCARD1) is a 110 kDa type I transmembrane glycoprotein of the lysosomal/endosomal-associated membrane glycoprotein (LAMP) family and the scavenger receptor family. Although CD68 primarily localizes to lysosomes and endosomes, its fraction circulates to the cell surface. By the heavily glycosylated extracellular domain CD68 binds to tissue- and organ-specific lectins or selectins. It is expressed mainly in cytoplasmic granules of monocytes/macrophages, granulocytes, and dendritic cells, but also e.g. in a proportion of epithelial tumours (diagnosis of poorly differentiated neoplasms).