The First Fully-Automated TRAcP5b Assay

An automated assay for the quantitative determination of Tartrate Resistant Acid Phosphatase 5b (TRAcP 5b) in human serum and heparin plasma.  The assay is intended for use as an aid in monitoring changes in bone metabolism in response to therapy.

TRAcP is an enzyme that is released from active osteoclasts, macrophages and dendritic cells 1.  There are 2 isoforms found in circulation; 5a is released from macrophages and dentritic cells whereas the 5b form is specific to active osteoclasts.  Relative to other bone resorption markers, circulating levels of TRAcP 5b display limited diurnal variation 2 and are unaffected by the fasting status of the patient, allowing the sample collection to be taken at any time of day.

As TRAcP 5b is cleared from circulation by the liver 3, kidney function has no effect on serum TRAcP 5b levels 2,4; thereby making this a potentially useful marker in patients with impaired renal function.

Features and Benefits

  • Only automated solution for measurement of TRAcP 5b in patient sera
  • Only marker reflecting bone degradation suitable for use with renal patients
  • Only bone resorption marker unaffected by fasting status useful in samples taken at any time of day
  • Excellent sensitivity and reproducible results – providing a useful tool in therapy monitoring
  • Supported by a comprehensive portfolio of both bone formation and resorption markers

View our Complete Bone Metabolism Assay Panel

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  1. Halleen JM. et al. Tartrate-resistant acid phosphatase 5b (TRACP 5b) as a marker of bone resorption.  Clin Lab. 2006;52(9-10):499-509
  2. Halleen JM. et al. Serum Tartrate-resistant Acid Phosphatase 5b is a Specific and Sensitive Marker of Bone Resorption.  Clin Chem. 2001;47(3):597-600
  3. Saunders PT. et al. The carbohydrate structure of porcine uteroferrin and the role of the high mannose chains in promoting uptake by the reticuloendothelial cells of the fetal liver. J Biol Chem. 1985;260:3658-3665.
  4. Hannon RA. et al. Clinical performance of immunoreactive tartrate resistant acid phosphatase isoform 5b as a marker of bone resorption. Bone. 2004;34:187-194.