CD68, also called Scavenger Receptor D1 (SR-D1) and LAMP-4, is a heavily glycosylated type I transmembrane glycoprotein that belongs to the LAMP family. CD68 is expressed in many tumor cell lines which could allow them to attach to selectins on vascular endothelium, facilitating their dissemination to secondary sites. CD68 plays a role in phagocytic activities of tissue macrophages, both in intracellular lysosomal metabolism and extracellular cell-cell and cell-pathogen interactions. It is a commonly used marker for macrophages. CD68 is also a biomarker of rheumatoid arthritis and Hodgkin's lymphoma. CD68 influences the functions of cells through NF-kB/focal adhesion kinase pathway (7). In addition, CD68 on macrophages binds tightly to both S100A8 and S100A9 to enhance the cell immunity.