Direct, enzyme-linked immunoassay for urinary deoxypyridinoline as a specific marker for measuring bone resorption.

Abstract

Several studies in recent years have shown that the pyridinium crosslinks of collagen provide good urinary markers of collagen degradation, primarily reflecting bone resorption. Most studies, however, were based on time-consuming HPLC assays of the crosslinks. We now describe the development of an immunoassay (ELISA) based on a monoclonal antibody for free deoxypyridinoline (Dpd) and its use in healthy individuals and patients with bone-related disorders to measure the urinary excretion of Dpd as an improved assessment of bone resorption rate. The Dpd antibody exhibited less than 1% cross-reaction with free pyridinoline and was shown to react only with free Dpd in urine, having no significant interaction with peptide forms of the crosslinks. The intra- and interassay variations were less than 10 and 15%, respectively. A total of 402 urine samples from patients and healthy volunteers were analyzed by both the immunoassay and HPLC. The ELISA results were highly correlated with those for total Dpd measured by HPLC over the full range of sample groups (r = 0.95). In normal adults, the excretion of Dpd (mean +/- SD) was 4.7 +/- 1.6 nmol/mmol creatinine, with about fivefold higher excretion rates in children. For 31 osteoporotic patients, the ELISA Dpd values (median 6.7; range 3.0-13.5 nmol/mmol Cr) were significantly higher (p < 0.0001) than the corresponding values for age- and sex-matched controls (median 4.0; range 1.8-7.4). The difference between the groups was similar for total Dpd by HPLC (osteoporotic: mean 12.8, range 4.8-30.7; controls: 6.6, range 3.0-18.1; p < 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

• Authors: S P Robins, H Woitge, R Hesley, J Ju, S Seyedin, M J Seibel
• Journal: Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research (J Bone Miner Res) Vol. 9 Issue 10 Pg. 1643-9 (Oct 1994) ISSN: 0884-0431 [Print] United States
• PMID: 7817812 (Publication Type: Clinical Trial, Comparative Study, Controlled Clinical Trial, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Amino Acids
• Antibodies, Monoclonal
• Biomarkers
• deoxypyridinoline

Topics

• Adult
• Aged
• Aged, 80 and over
• Aging (urine)
• Amino Acids (urine)
• Animals
• Antibodies, Monoclonal
• Antibody Specificity
• Biomarkers (urine)
• Bone Resorption (urine)
• Breast Neoplasms (urine)
• Chromatography, High Pressure Liquid
• Enzyme-Linked Immunosorbent Assay
• Female
• Humans
• Hyperparathyroidism (urine)
• Kidney Failure, Chronic (urine)
• Male
• Mice
• Middle Aged
• Osteitis Deformans (urine)
• Osteoporosis (urine)
• Reproducibility of Results