Two-miRNA–based finger-stick assay for estimation of absorbed ionizing radiation dose

Abstract

Nuclear radiation and radioactive fallouts resulting from a nuclear weapon detonation or reactor accidents could result in injuries affecting multiple sensitive organs, defined as acute radiation syndrome (ARS). Rapid and early estimation of injuries to sensitive organs using markers of radiation response is critical for identifying individuals who could potentially exhibit ARS; however, there are currently no biodosimetry assays approved for human use. We developed a sensitive microRNA (miRNA)–based blood test for radiation dose reconstruction with ±0.5 Gy resolution at critical dose range. Radiation dose–dependent changes in miR-150-5p in blood were internally normalized by a miRNA, miR-23a-3p, that was nonresponsive to radiation. miR-23a-3p was not highly expressed in blood cells but was abundant in circulation and was released primarily from the lung. Our assay showed the capability for dose estimation within hours to 1 week after exposure using a drop of blood from mice. We tested this biodosimetry assay for estimation of absorbed ionizing radiation dose in mice of varying ages and after exposure to both improvised nuclear device (IND)–spectrum neutrons and gamma rays. Leukemia specimens from patients exposed to fractionated radiation showed depletion of miR-150-5p in blood. We bridged the exposure of these patients to fractionated radiation by comparing responses after fractionated versus single acute exposure in mice. Although validation in nonhuman primates is needed, this proof-of-concept study suggests the potential utility of this assay in radiation disaster management and clinical applications.

Serum miRNA-based signature indicates radiation exposure and dose in humans: a multicenter diagnostic biomarker study

“…Several classes of biomarkers related to oxidative stress [41], inflammatory and immune response [42], metabolomics [43] and gene expression signatures [44] have been vigorously tested in recent years, with limited success. Multiple studies conducted on animal models [11,[18][19][20]22,40] showed that miRNAs may reliably reflect radiation response and act as functional dosimeters predicting not only the actual dose given but also the biological impact of radiation on the organism [18]. Over the past few years, our group has gradually gathered evidence suggesting that multiple radiation-inducible miRNAs are evolutionarily conserved and that results observed in animals may be translated to humans [18,19].…”

“…Soon after such an event, it is infeasible to determine who received lethal doses of radiation, as typical diagnostic tests are technically difficult and time consuming [39]. A similar concept was recently investigated in a study where the Authors proposed the use of miR-150-5p normalized to one internal reference miRNA to estimate the absorbed radiation dose [40]. The assay, however, was developed and calibrated only for the use in mice, preventing direct assessment of its performance in our dataset of human serum miRNA expression following TBI.…”

Long and short non-coding RNA and radiation response: a review

“…This study utilized blood from C57BL/6 mice exposed to a range of doses. 102 In a model of human blood exposed ex vivo to doses of 0.5, 1, 2.5 and 5 Gy 60 Co irradiation, Lee et al described changes in miRNA expression that could be used to distinguish each dose from control samples. 103 However, in vivo animal studies must be performed to develop clinical biomarkers.…”

“…109 tuberculosis, 116 and breast cancer. 117 Yadav et al reported their radiation-induced miRNA expression results using a single drop of mouse blood, 102 which provides a promising starting point towards a minimally invasive microfluidic device that can accurately characterize radiation dose, prognosis, and mortality.…”

“…Once triaged into those two categories, additional markers could further distinguish extent of exposure.Equally important, a set of biomarkers must have some normalizing control marker since it would not be feasible to obtain baseline RNA expression values for all victims before a nuclear incident occurs. We have previously used mRNA Rplp0 as a control83 ; Yadav et al normalized miRNA levels to miR-23a-3p 102. An effective RNA biomarker signature may draw upon the strengths of miRNA, lncRNA, circRNA, and mRNA to improve diagnostic and prognostic capabilities.A decision analysis approach is being considered that might be better able to guide medical providers in an emergency scenario as acute radiation syndrome symptoms develop.…”