Related Experiment Video
Updated: Jul 19, 2026

Skeletal Phenotype Analysis of a Conditional Stat3 Deletion Mouse Model
Published on: July 3, 2020
Tartrate-resistant acid phosphatase 5b (TRACP 5b) as a marker of bone resorption
Jussi M Halleen1, Sari L Tiitinen, Hannele Ylipahkala
1Institute ofBiomedicine, Department ofAnatomy, University of Turku, Finland. jussi.halleen@pharmatest.fi
Abstract:
Tartrate-resistant acid phosphatase (TRACP) is an enzyme that is expressed in high amounts by bone resorbing osteoclasts, inflammatory macrophages and dendritic cells. Two forms of TRACP circulate in human blood, TRACP 5a derived from macrophages and dendritic cells, and TRACP 5b derived from osteoclasts. Recent data have demonstrated the utility of TRACP 5b as a marker of osteoclast number and bone resorption, and serum TRACP 5a as a marker of inflammatory conditions. This review summarizes the scientific knowledge on the role of TRACP in osteoclastic bone resorption, the mechanism of TRACP 5b generation in osteoclasts and its secretion into the blood circulation, the methodology of measuring TRACP 5b, diagnostic evidence for the use of TRACP 5b as a resorption marker, and characteristics of TRACP 5b compared to other commonly used bone turnover markers.
Related Concept Videos
Osteoclasts in Bone Remodeling
Bone Remodeling
Hormones and Bone Tissue
Hormones That Influence Osteoblasts and/or Maintain the Matrix
Several hormones are necessary for controlling bone growth and maintaining the bone matrix. The pituitary gland secretes growth hormone (GH), which, as its name implies, controls bone growth. This happens in several ways: first, it triggers chondrocyte...
Roles of Electrolytes: Calcium and Phosphate
The calcium concentration in blood plasma is primarily regulated...

