A simplified protocol for gene expression-based biological dosimetry using peripheral whole blood.

Area of Science:

• Radiation biology
• Molecular biology
• Biotechnology

Background:

• Radiation biodosimetry aims to assess radiation exposure levels.
• Gene expression analysis in peripheral blood cells offers a high-throughput biodosimetry approach.
• Optimizing sample handling is crucial for reliable gene expression biodosimetry.

Purpose of the Study:

• To evaluate the impact of storage temperature and incubation time on radiation-responsive gene expression in whole blood.
• To identify optimal conditions for enhancing gene expression-based radiation biodosimetry.
• To simplify sample processing for biodosimetry applications.

Main Methods:

• Whole peripheral blood samples were ex vivo irradiated at various doses (0.5-4 Gy).
• Irradiated samples were incubated at 4°C or 37°C for 2, 4, and 24 hours.
• Quantitative reverse transcription PCR (qRT-PCR) was used to analyze mRNA expression of 19 radiation-responsive genes.

Main Results:

• Incubation at 4°C did not significantly alter gene expression compared to controls.
• Incubation at 37°C for 24 hours induced significant overexpression in 14 of 19 genes.
• DDB2 and FDXR showed the most significant and consistent upregulation at 37°C.

Conclusions:

• Incubating undiluted whole blood at 37°C for 24 hours provides optimal conditions for radiation-responsive gene expression analysis.
• This optimized protocol enhances the sensitivity of gene expression biodosimetry.
• The findings support the use of physiological temperature incubation for up to 24 hours in biodosimetry triage applications.