title: Quantification of tartrate resistant acid phosphatase activity using a computerized image analysis system.
abstract: Tartrate resistant acid phosphatase (TRAP) has been accepted as a marker for identification of osteoclasts. A method is reported here for quantitating TRAP using an image analysis system. The amount of the enzyme specific to osteoclasts can be used to differentiate osteoclasts from other cells capable of TRAP expression. TRAP expression characteristic of the osteoclast was compared with that of multi-nucleated giant cells (MNGC)s recruited to the site of subcutaneously implanted mineralized bone matrix. Two weeks post-implantation, the pellets were removed and processed for the demonstration of TRAP along with rat proximal tibiae. A large amount of TRAP was consistently expressed by the in situ osteoclasts. The MNGCs associated with the mineralized bone implants expressed little if any TRAP reaction product. Using this system, the amount of TRAP reaction product or any other enzyme reaction product expressed can be objectively and reproducibly quantitated.
authors.affiliation: Department of Cell Biology, Neurobiology and Anatomy, Stritch School of Medicine, Loyola University of Chicago, Maywood, Illinois 60153.
authors.forename: J D
authors.initials: JD
authors.lastname: Kelly
authors.forename: J A
authors.initials: JA
authors.lastname: McNulty
authors.forename: G B
authors.initials: GB
authors.lastname: Schneider
mesh_terms: D000135:Acid Phosphatase / Q000032:analysis* / Q000378:metabolism; D000818:Animals; D003593:Cytoplasm / Q000201:enzymology; D004351:Drug Resistance; D015726:Giant Cells / Q000201:enzymology; D007091:Image Processing, Computer-Assisted; D008297:Male; D010010:Osteoclasts / Q000201:enzymology; D051381:Rats; D015203:Reproducibility of Results; D013644:Tartrates / Q000494:pharmacology*; D013977:Tibia / Q000166:cytology; D014617:Vacuoles / Q000201:enzymology
chemical_list: D013644:Tartrates; D000135:Acid Phosphatase; C029768:tartaric acid