Cell Biology and Toxicology

, Volume 25, Issue 1, pp 73–80 | Cite as

Detection of excision repaired DNA damage in the comet assay by using Ara-C and hydroxyurea in three different cell types

  • A. Güerci
  • D. Liviac
  • R. Marcos


Because of its characteristics, the comet assay has been used to evaluate the ability of virtually any type of eukaryotic cell to repair different kinds of DNA damage, including double and single strand breaks and base damage. The ability to detect excision repair sites using the alkaline version can be enhanced by the inclusion of repair inhibitors, DNA synthesis inhibitors, or chain terminators. In this sense, we evaluated the ability of hydroxyurea (HU) and cytosine arabinoside (Ara-C), for detecting lesions produced by the alkylating agents ethyl methanesulfonate (EMS) and methyl methanesulfonate (MMS) in three different cell systems. Two hundred cells for experimental point were analyzed in the alkaline version of the comet assay, and the results are evidences of the utility of the assay to detect alkylation of bases in the cells lines MRC-5 and TK-6, as the treatment with HU +Ara-C significantly increases both the basal and induced frequency of DNA damage. The use of whole blood, although it detected the effects of MMS, with and without repair inhibitors, failed to detect the effect of the selected dose of EMS and does not permit detection increases in the background level.


Comet assay Ara-C Hydroxyurea Alkylating agents Human cell lines 



Güerci was supported by a postdoctoral fellowship from the Spanish Ministry of Education and Science. D. Liviac was supported by a postgraduate fellowship from the UAB. This investigation has been supported in part by the Generalitat de Catalunya (CIRIT, 2005SGR-00136) and the UE (NewGeneris, Food-CT-2005–016320).


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Copyright information

© Springer Science+Business Media B.V. 2007

Authors and Affiliations

  1. 1.Grup de Mutagènesi, Departament de Genètica i de Microbiologia, Edifici CnUniversitat Autònoma de BarcelonaBellaterraSpain
  2. 2.CIBER Epidemiología y Salud PúblicaISCIIIBarcelona, Spain
  3. 3.Departament de Genètica i de Microbiologia, Facultat de BiociènciesUniversitat Autònoma de BarcelonaCerdanyola del VallèsSpain
  4. 4.Centro de Investigaciones en Genética Básica y AplicadaUniversidad Nacional de la PlataLa PlataArgentina

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