Does Cell Culture Type And Blood Transport Temperature Affect Dicentric Yield And Radiation Dose Assessment?

Background: The metaphase-spread-based dicentric chromosome assay (DCA) is the “gold standard” biodosimetry method for radiation dose assessment. However, practical issues influencing dose assessment by DCA, such as cell culture type and blood transport temperature are not addressed. Purpose: To fill the research gaps, we studied the effects of short-term cell culture type, the use of whole blood versus isolated lymphocyte cultures, and the influence of refrigerated blood transport conditions. Materials and methods: Human peripheral blood was irradiated with Co (cobalt-60) gamma rays and subjected to different temperature/shipment conditions and to shortterm culture procedures. Blood transport temperature was measured using temperature data loggers. Frequency of dicentrics and gamma-H2AX persistent expression were estimated. Results: Dicentric yield was identical in both culture types. Immediate exposure of irradiated samples to refrigeration increased dicentric yield, correlating with increased gamma-H2AX positive cells. Conclusion: The whole-blood culture method can be used for DCA instead of the isolated lymphocyte culture to increase throughput in radiation mass casualty events. Storage/shipment of blood under refrigerated conditions immediately after radiation exposure should be avoided because it may result in dose overestimation. An increase in dicentrics was associated with an increase in persistent gamma-H2AX expression, suggesting DNA repair inhibition under refrigeration.