Gene Expression in Low- and High-Dose-Irradiated Human Peripheral Blood Lymphocytes: Possible Applications for Biodosimetry

Abstract

To overcome the limitations of existing biodosimetry methods, we examined dose- and time-dependent gene expression changes in human peripheral blood lymphocytes after exposure to low-, medium- and high-dose ionizing radiation and searched for genes suitable for predicting radiation doses in the low-dose range. Additionally, the experiments are intended to provide new insights into the biological effects of exposures to low-, medium- and high-dose radiation. Gene expression analysis using whole human genome DNA microarrays was performed in human blood from six healthy donors irradiated ex vivo with 0, 0.02, 0.1, 0.5, 1, 2 and 4 Gy (γ rays, (137)Cs) at 6, 24 and 48 h after high-dose exposure (0.5-4 Gy), and at 24 and 48 h after low-dose exposures of 0.02 or 0.1 Gy. DNA microarray-based alterations in gene expression were found in a wide dose range in vitro and allowed us to identify nine genes with which low radiation doses could be accurately predicted with a sensitivity of 95.6%. In the low-, medium- and high-dose range, expression alterations increased with increasing dose and time after exposure, and were assigned to different biological processes such as nucleosome assembly, apoptosis and DNA repair response. We conclude from our results that gene expression profiles are suitable for predicting low-dose radiation exposure in a rapid and reliable manner and that acute low-dose exposure, as low as 20 mGy, leads to well-defined physiological responses in human peripheral blood lymphocytes.

Comparable dose estimates of blinded whole blood samples are obtained independently of culture conditions and analytical approaches. Second RENEB gene expression study

“…It has been reported many times that the quantification of gene expression in response to radiation exposure by microarray technology is robust and reliable (Paul & Amundson 2008;Boldt et al 2012;Knops et al 2012), and the obtained gene signatures derived in ex situ irradiated blood are shown to be predictive for the radiation dose in vitro as well as in vivo (Paul et al 2011). The gene signature developed by Boldt et al (2012) was reported to be robust in terms of dose prediction.…”

“…Detailed analysis protocols for Labs 1, 2 and 3 are described in Abend et al (2016). DNA microarrays (44 k whole human genome, G4112F, Agilent) were performed according to the manufacturer's protocols and as described in Knops et al (2012).…”

“…Dose assessment in irradiated blood samples can be obtained by either using dose predictive gene or exon signatures (Paul & Amundson 2008;Kabacik et al 2011;Boldt et al 2012;Knops et al 2012;Lucas et al 2014;Macaeva et al 2016) or by monitoring the modification of transcription of single radiation-responsive genes like ferredoxin reductase (FDXR) (Manning et al 2013;Abend et al 2016).…”

“…In ex vivo studies, several protocols have been used such as cultured peripheral blood mononuclear cells (PBMC) (Dressman et al 2007;Meadows et al 2008Meadows et al , 2010Sprung et al 2011;Boldt et al 2012;Knops et al 2012;Riecke et al 2012;Macaeva et al 2016), cultured whole blood diluted with media Brzoska andKruszewski 2015, Abend et al 2016) or undiluted whole blood (Manning et al 2013). However, none of these studies have addressed the role of blood culture methods during the incubation time at 37 C following radiation exposure.…”

Gene Expression Biodosimetry: Quantitative Assessment of Radiation Dose with Total Body Exposure of Rats

“…We compared our findings with a previously used gene in GE biodosimetry, FDXR (Boldt et al 2012;Kabacik et al 2011;Knops et al 2012;Manning and Rothkamm;Paul and Amundson, 2008), which is regulated by p53 family and with our previous in vitro study (Khodamoradi et al In Press). In our pervious study, we found the dose response curve of the FDXR and RAD51 genes in response to different doses and 6 and 18 MV beam energies in human PBLs.…”