Amylase and blood cell-count hematological radiation-injury biomarkers in a rhesus monkey radiation model-use of multiparameter and integrated biological dosimetry

Effective medical management of suspected radiation exposure incidents requires the recording of dynamic medical data (clinical signs and symptoms), biological assessments of radiation exposure, and physical dosimetry in order to provide diagnostic information to the treating physician and dose assessment for personnel radiation protection records. The need to rapidly assess radiation dose in mass-casualty and population-monitoring scenarios prompted an evaluation of suitable biomarkers that can provide early diagnostic information after exposure. We investigated the utility of serum amylase and hematological blood-cell count biomarkers to provide early assessment of severe radiation exposures in a non-human primate model (i.e., rhesus macaques; n = 8) exposed to whole-body radiation of Co-60-gamma rays (6.5 Gy, 40 cGy min(-1)). Serum amylase activity was significantly elevated (12.3 +/- 3.27- and 2.6 +/- 0.058-fold of day zero samples) at I and 2-days, respectively, after radiation. Lymphocyte cell counts decreased (<= 15% of day zero samples) 1 and 2 days after radiation exposure. Neutrophil cell counts increased at day one by 1.9(+/- 0.38)-fold compared with levels before irradiation. The ratios of neutrophil to lymphocyte cell counts increased by 13(+/- 2.66)- and 4.23 (+/- 0.95) -fold at 1 and 2 days, respectively, after irradiation. These results demonstrate that increases in serum amylase activity along with decreases of lymphocyte counts, increases in neutrophil cell counts, and increases in the ratio of neutrophil to lymphocyte counts I day after irradiation can provide enhanced early triage discrimination of individuals with severe radiation exposure and injury. Use of the biodosimetry assessment tool (BAT) application is encouraged to permit dynamic recording of medical data in the management of a suspected radiological casualty. (c) 2007 Elsevier Ltd. All rights reserved.