TY  - JOUR
A1  - Bankoglu, Ezgi Eyluel
A1  - Stipp, Franzisca
A1  - Gerber, Johanna
A1  - Seyfried, Florian
A1  - Heidland, August
A1  - Bahner, Udo
A1  - Stopper, Helga
T1  - Effect of cryopreservation on DNA damage and DNA repair activity in human blood samples in the comet assay
JF  - Archives of Toxicology
N2  - The comet assay is a commonly used method to determine DNA damage and repair activity in many types of samples. In recent years, the use of the comet assay in human biomonitoring became highly attractive due to its various modified versions, which may be useful to determine individual susceptibility in blood samples. However, in human biomonitoring studies, working with large sample numbers that are acquired over an extended time period requires some additional considerations. One of the most important issues is the storage of samples and its effect on the outcome of the comet assay. Another important question is the suitability of different blood preparations. In this study, we analysed the effect of cryopreservation on DNA damage and repair activity in human blood samples. In addition, we investigated the suitability of different blood preparations. The alkaline and FPG as well as two different types of repair comet assay and an in vitro hydrogen peroxide challenge were applied. Our results confirmed that cryopreserved blood preparations are suitable for investigating DNA damage in the alkaline and FPG comet assay in whole blood, buffy coat and PBMCs. Ex vivo hydrogen peroxide challenge yielded its optimal effect in isolated PBMCs. The utilised repair comet assay with either UVC or hydrogen peroxide-induced lesions and an aphidicolin block worked well in fresh PBMCs. Cryopreserved PBMCs could not be used immediately after thawing. However, a 16-h recovery with or without mitotic stimulation enabled the application of the repair comet assay, albeit only in a surviving cell fraction.
KW  - human biomonitoring
KW  - DNA damage
KW  - DNA repair
KW  - comet assay
KW  - blood samples
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-265326
VL  - 95
IS  - 5
ER  -