European Standards Committee of Urinary (DNA) Lesion Analysis

There is growing evidence that, rather than simply being a non-invasive marker of whole body oxidative stress, measurement of urinary lesions, such as 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), may, to some extent, reflect the repair of oxidised DNA and deoxynucleotides, although their precise provenance is far from clear. A discrepancy in basal urinary 8-oxodG levels has been noted when comparing chromatographic techniques (e.g. GC/MS following prior HPLC pre-purification, or LC-MS/MS, or LC-EC) with ELISA, although all techniques have been shown to discriminate between diseased and healthy subjects, and possess good within-technique agreement. ELISA has received widespread use, and is clearly amenable to the greatest number of laboratories, however, this discrepancy continues to raise questions regarding its utility. Understanding the basis of this discrepancy will aid our understanding of the significance of urinary lesions.

Furthermore, performing inter-laboratory validation of assays for urinary 8-oxodG measurement would provide robust methods for widespread dissemination and application. Hitherto, this has been performed in a limited fashion, and the discrepancies remain unaddressed. Finally, there is growing clinical interest in the measurement of urinary 8-oxodG, as a means to determine the role of oxidative stress in disease, and evaluate intervention strategies. As with other clinical parameters, a reference range must first be determined.

Objectives of ESCULA:

1. To compare a multiple (n > 4), different methods for the analysis of urinary 8-oxodG.
2. To compare methods for urinary creatinine concentration
3. Evaluate correcting urinary lesion measurements for (i) creatinine, (ii) collection over a 24 hr period.
4. To identify consensus between labs and/or techniques and investigate the basis for any discrepancy.
5. To achieve a better understanding of the sources of DNA lesions in urine
6. Develop a biobank of urine samples from healthy individuals, in order to establish a reference range for urinary 8- oxodG determined by the above methods.
7. Examination of how levels of other urinary lesions compare to urinary 8-oxodG levels.
8. Examination of the significance of urinary 8-oxodG levels in urine, in healthy individuals, and those with disease, as a prelude to application in large, multi-centre trials.
9. Public engagement in science. Develop a user-friendly link from the ESCULA website informing the general public, in lay terms, and main EU languages: what are reactive oxygen species (ROS)?; ROS and disease; combating free radicals; ROS research

ESCULA Membership and Publications