Effect of blood storage on radiation-induced micronuclei in human lymphocytes

Delayed Mitogenic Stimulation Decreases DNA Damage Assessed by Micronucleus Assay in Human Peripheral Blood Lymphocytes after 60CO Irradiation

“…2). The results are different from the report of Lee et al (1999), in which 2Gy of gamma radiation exposed blood lymphocytes stored at 5°C or 22°C even for 96 and 120 hours and then stimulated with PHA did not show any differences in their yield of MN. Hoffmann et al (2002), Krishnaja and Sharma (2006) have been reported that the yield of DC and MN is increasing by the prolonged culture of lymphocytes with PHA at different time intervals.…”

“…Factors such as prolonged culture time with PHA, delayed mitogenic stimulation and late arising first division metaphase after exposure of human PBL in G0 influenced presence of increased chromosomal aberrations and MN frequency (Holmberg et al 1998;Hoffmann et al 2002;Krishnaja and Sharma 2006). Contrarily, it was reported that exposed blood maintained at 22°C or 5°C, did not show any changes in the yield of MN (Lee et al 1999). Thus there is no consistency and conflicting results have been reported on the influences of temperature and PHA stimulation on the yield of MN.…”

Cytokinesis-block micronucleus cytome assay

“…TROUBLESHOOTING Blood and cell storage conditions The published evidence available suggests that storage of blood between 5 and 22 1C for up to 24 h has no significant impact on baseline or radiation-induced MN frequency 73 ; however, these observations need to be further verified and replicated. It is possible to perform the CBMN Cyt assay using cryopreserved lymphocytes, but there are conflicting reports on whether cryopreservation alters the frequency rate of MN in BN cells 74,75 , which means that it is essential to optimize and verify that the freezing and thawing protocol used does not induce DNA damage.…”

HUman MicroNucleus project: international database comparison for results with the cytokinesis-block micronucleus assay in human lymphocytes: I. Effect of laboratory protocol, scoring criteria, and host factors on the frequency of micronuclei

“…More recently, Fenech [1998] reported that a comparative study of two different culture media, RPMI 1640 and McCoy, did not reveal differences in the MN frequencies. Other studies have addressed issues dealing with blood sampling, such as alternatives to venipuncture [Lee et al, 1997] or the effect of storage [Lee et al, 1999]. A number of articles have been published that recommended changes to the standard methods, although there has been no coordinated evaluation of the effects of different methodological aspects on the outcome frequency.…”