Anti-Human CD68 (Clone KP1) - FITC (C924-GRP)

CD68 is a heavily glycosylated type I transmembrane glycoprotein belonging to the lysosomal-associated membrane protein (LAMP) family and may play a role in endocytosis or lysosomal traffic and phagocytic activities1. CD68 localizes to endosome- or lysosome-like structures2. Additionally, LAMPS have been implicated in tumor cell metastasis and are over-expressed on the surface of metastatic compared with nonmetastatic cell lines3. KP1 was originally used as a pan-monocytic/macrophage marker against CD68; however, CD68 is not a macrophage specific antigen and KP1 is known to stain neutrophils and other non-macrophage-like cells4,5,6,7,8. KP1 reacts against CD68 in a wide range of healthy4 and disease-associated (rheumatoid arthritis and osteoarthritis)5 tissues as well as a variety of neoplasms9, tumor cell lines7, and tumor-associated macrophages 8. KP1 detects a fixation-resistant epitope10 that is likely glycan-based1,9 which is shared by many cell types7. KP1 was developed by immunizing Balb/c mice against a lysosomal fraction of human lung 10. Hybridoma supernatants derived from spleen cells were screened on cryostat human lung and tonsil sections as well as paraffin wax sections of lung tissue fixed in formol saline.