Quantitative immunohistochemical determination of 8-hydroxy-2'-deoxyguanosine by a monoclonal antibody N45.1: its application to ferric nitrilotriacetate-induced renal carcinogenesis model
Toyokuni, S.; Tanaka, T.; Hattori, Y.; Nishiyama, Y.; Yoshida, A.; Uchida, K.; Hiai, H.; Ochi, H.; Osawa, T.
Laboratory Investigation; A Journal of Technical Methods and Pathology 76(3): 365-374
1997
ISSN/ISBN: 0023-6837 PMID: 9121119 Document Number: 478403
The DNA base-modified product 8-hydroxy-2'-deoxyguanosine (8-OHdG) is one of the most commonly used markers for the evaluation of oxidative DNA damage. A monoclonal antibody specific for 8-OHdG (N45.1) was characterized and applied in quantitative immunohistochemistry. N45.1 recognized both the modified base and deoxyribose structure of 8-OHdG and required a concentration two orders higher of 8-hydroxyguanosine as a competitor in the ELISA. In addition, N45.1 did not cross-react with the original four deoxyribonucleosides, other DNA base-modified products such as 8-hydroxy-2'-deoxyadenosine and O-6-methyl-2'-deoxyguanosine, or urine components such as uric acid, creatine, and creatinine. A ferric nitrilotriacetate-induced rat renal carcinogenesis model was used for the evaluation of quantitative immunohistochemistry. The 8-OHDG index of quantitative immunohistochemistry, as analyzed by NIH Image freeware, correlated reasonably well with the 8-OHdG amount determined by high-performance liquid chromatography with an electrochemical detector - except for a difference in peak time, which could be attributed to the selection of target location. The present method has advantages over the high-performance liquid chromatography/electrochemical detector, gas chromatography/mass spectrometry, and 32P-postlabeling methods in that it allows localization of 8-OHdG to be specified without the risk of artifactual production of 8-OHdG during the DNA extraction and hydrolytic processes.