Extension of lymphocyte viability for radiation biodosimetry: Potential implications for radiological/nuclear mass casualty incidents

Abstract

Dicentric chromosome assay (DCA) is routinely used for estimating the absorbed radiation dose in exposed humans. Optimal lymphocyte viability is crucial for reliable dose estimation and most cytogenetic laboratories prefer the receipt of blood samples within 24 to 36 hours after collection. Delays in the shipment/receipt of samples can occur sometimes under certain unforeseen circumstances: (1) Adverse weather conditions, (2) distant location of blood collection sites, and (3) shipping and handling of a large number of samples after radiological/nuclear mass casualty incident(s). To circumvent some of these limitations, we evaluated the suitability of ex vivo irradiated blood samples stored in the presence of phytohemagglutinin (PHA) for 7 days at ambient temperature (22‐24°C) for radiation biodosimetry. Blood samples stored in the presence of PHA for up to 7 days showed a higher mitotic index than blood samples stored without PHA. To verify the use of stored blood samples for DCA, frequencies of X‐rays induced dicentric chromosomes were analyzed in the blood samples that were cultured either 24 hours after exposure or 7 days later after storage. Our results indicate that storage of ex vivo irradiated blood samples in the presence of PHA at ambient temperature was found optimal for DCA and that the radiation doses estimated by dicentric chromosome frequencies were grossly similar between the fresh and stored blood samples. Our study suggests that reliable and accurate biodosimetry results can be obtained for triage using blood samples stored for up to a week at ambient temperature in the presence of PHA.

Use of human lymphocyte G0 PCCs to detect intra- and inter-chromosomal aberrations for early radiation biodosimetry and retrospective assessment of radiation-induced effects

“…Procedure for the fluorescence in situ hybridization (FISH) technique using peptide nucleic acid (PNA) based human telomeric and centromeric DNA probes was essentially the same as described in our previous studies [39, 40]. A cocktail of probe specific for human chromosomes 1, 2 and 4 was obtained from MetaSystems and the FISH procedure using this probe was performed essentially as described by the manufacturers.…”

A High Throughput Approach to Reconstruct Partial-Body and Neutron Radiation Exposures on an Individual Basis

“…High-throughput automatic biodosimetry is crucial for an effective response to a large-scale radiological event like an improvised nuclear device (IND) detonation [1][2][3][4][5][6][7][8][9][10] . The importance of high-throughput biodosimetry is well recognized, because traditional manual scoring assays are labor intensive, time consuming and impractical after a large-scale radiological/nuclear event 3,21,[94][95][96] . Numerous enhanced approaches based on cytogenetic damage [37][38][39][40][41][43][44][45][46][48][49][50][51][54][55][56] and other types of radiation biomarkers [57][58][59][61][62][63][64][65][66][67][68][69] have been proposed and implemented.…”