Multiple parameter radiation injury assessment using a nonhuman primate radiation model-biodosimetry applications

Area of Science:

• Biomedical Sciences
• Radiation Biology
• Toxicology

Background:

• Urgent need for rapid radiation injury assessment in mass casualty events.
• Current biomarkers require evaluation for early diagnostic triage post-radiation exposure.

Purpose of the Study:

• Evaluate available biomarkers for early diagnostic triage after radiation exposure.
• Assess the utility of hematology and blood chemistry in a nonhuman primate model.

Main Methods:

• Total-body irradiation (TBI) of nonhuman primates (Macaca mulatta) with 6.5-Gy Cobalt-60 gamma rays.
• Monitoring of C-reactive protein (CRP), blood cell counts (lymphocytes, neutrophils), and serum amylase activity over time.
• Discriminant analysis using multiple biomarkers to differentiate exposed from non-exposed individuals.

Main Results:

• Significant time-dependent changes observed in CRP, lymphocyte counts, neutrophil-to-lymphocyte ratio, and serum amylase post-TBI.
• Lymphocytes decreased to 5-8% of baseline levels by 1-4 days post-TBI.
• Discriminant analysis achieved 100% separation of exposed vs. non-exposed samples at 24 hours post-TBI using four biomarkers.

Conclusions:

• Multiple biomarkers, including CRP, lymphocytes, neutrophils, and amylase, can effectively discriminate radiation-exposed individuals.
• These findings support the practical use of a multi-parameter biomarker approach for radiation exposure assessment.
• Justifies further research, including a dose-response study in rhesus macaques.