Tartrate-resistant acid phosphatase (trap) activity as osteoclastic marker: Comparison between cytochemical assessment and serum assay

Abstract Background: Tartrate-resistant acid phosphatase (TRAP; EC 3.1.3.2) is a product of osteoclasts and a biochemical marker of bone resorption rate. However, erythrocytes and platelets contribute to total TRAP activity in serum, reducing the specificity of direct biochemical assays in serum. Osteoclast TRAP is also known as type-5 TRAP and is antigenically unique. Immunoassays are sought to improve the specificity and sensitivity of TRAP as a bone marker. Methods: We developed two colorimetric microplate assays for type-5 TRAP: an enzyme capture immunoassay to measure antibody-bound enzymatic activity, and a two-site immunoassay to measure bound enzyme protein. Both use the same monoclonal antibody (14G6) to capture type-5 TRAP, which permits determination of specific activity of serum TRAP in health and disease. Results: Both TRAP assays were linear from one-tenth to fivefold the mean value in 18 healthy subjects. In these subjects, the mean (SD) TRAP activity was 3.2 (0.54) U/L for the enzyme capture assay and 37 (13) μg/L for the two-site assay. Mean TRAP activity was not significantly increased in 64 patients with endstage renal disease requiring hemodialysis (HD) or 99 unselected patients with rheumatic diseases. By contrast, TRAP protein was increased in both the HD and rheumatic disease groups. The specific activity of TRAP in the 17 of 64 HD sera that had increased TRAP activity (0.088 U/μg) was similar to that in healthy subjects (0.091 U/μg). By contrast, the specific activity of TRAP in the 31 of 99 rheumatic sera with increased TRAP protein (0.035 U/μg) was significantly decreased. Conclusions: Wide sample distributions for TRAP activity in HD patients and TRAP protein in rheumatic disease patients suggest the presence of subpopulations of HD patients with increased TRAP activity and of rheumatic patients with increased TRAP protein. Each assay for TRAP activity and protein may have its own biological significance and clinical applications in specific groups of patients.

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The fluorescent simultaneous azo dye technique for demonstration of tartrate-resistant acid phosphatase (TRAP) activity in osteoclast-like multinucleate cells

Journal of Bone and Mineral Metabolism ◽

10.1007/bf01771320 ◽

1995 ◽

Vol 13 (2) ◽

pp. 71-76 ◽

Cited By ~ 6

Author(s):

Toshio Tsuchiya ◽

Yoshiro Matsumoto ◽

Saburo Kurihara

Keyword(s):

Acid Phosphatase ◽

Azo Dye ◽

Tartrate Resistant Acid Phosphatase ◽

Multinucleate Cells ◽

Trap Activity

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Tartrate-resistant acid phosphatase as a biomarker of bone turnover in dog

Arquivo Brasileiro de Medicina Veterinária e Zootecnia ◽

10.1590/s0102-09352011000100007 ◽

2011 ◽

Vol 63 (1) ◽

pp. 40-45 ◽

Cited By ~ 6

Author(s):

C.P Sousa ◽

F Nery ◽

J.T Azevedo ◽

C.A Viegas ◽

M.E Gomes ◽

...

Keyword(s):

Acid Phosphatase ◽

Individual Variation ◽

Bone Alkaline Phosphatase ◽

Tartrate Resistant Acid Phosphatase ◽

Biological Variability ◽

Trap Activity ◽

Non Invasive ◽

Serum Minerals ◽

Serum Trap

Values of serum tartrate-resistant acid phosphatase ( TRAP) activity were obtained in adult dogs and its biological variability was assessed. Nine healthy skeletally mature Portuguese Podengo dogs were used for the determination of TRAP, total and bone alkaline phosphatase serum activities, and also to study their relationship with serum minerals, namely calcium (Ca), phosphorous (P), and magnesium (Mg). The serum TRAP activity was 2.19±0.56IU/mL, with intra-individual variation of 18.3% and inter-individual variation of 25.6%. Significant correlations were observed between serum TRAP activity and Ca (r=-0.3431; P<0.05), Ca and Mg (r=-0.787; P<0.01), and TRAP and Mg (r=0.397; P<0.05). The results indicate that serum TRAP activity in dog could be of great value in research and in clinical practice, providing complementary non-invasive information on bone metabolism

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Tartrate-resistant Acid Phosphatase (TRAP) Activity in Serum: Potential Use in Assessing Bone Resorption in Patients with Multiple Myeloma

The International Journal of Biological Markers ◽

10.1177/172460089000500202 ◽

1990 ◽

Vol 5 (2) ◽

pp. 61-64 ◽

Cited By ~ 4

Author(s):

M. Monti ◽

A. Scazzoso ◽

G. Calzaferri ◽

I. Santi ◽

E. D'Aprile ◽

...

Keyword(s):

Multiple Myeloma ◽

Acid Phosphatase ◽

Bone Resorption ◽

Bone Lesions ◽

Tartrate Resistant Acid Phosphatase ◽

Trap Activity ◽

Serum Trap ◽

The Difference ◽

Young Subjects ◽

Hydroxyproline Excretion

We measured serum tartrate-resistant acid phosphatase (TRAP) activity in 120 healthy subjects and 35 patients with multiple myeloma as well as urinary hydroxyproline excretion in the myeloma patients. Young subjects (0-18 years) showed higher TRAP levels (ANOVA p < 0.01) compared with the other age classes due to the more active bone remodelling processes associated with growth. Myeloma patients with bone lytic lesions (MM+) showed higher serum TRAP values than controls (p < 0.01). Hydroxyproline excretion was higher in MM + patients but the difference between patients with and without bone lesions was not statistically significant. Our data suggest that serum TRAP activity may be a suitable, simple biochemical test to assess bone turnover in patients with multiple myeloma but that its clinical usefulness as a marker of bone resorption needs further evaluation.

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