Title: Effect of total body irradiation on late lung effects: hidden dangers.

Authors: Johnston, Carl J; Manning, Casey; Hernady, Eric; Reed, Christina; Thurston, Sally W; Finkelstein, Jacob N; Williams, Jacqueline P

Published In Int J Radiat Biol, (2011 Aug)

Abstract: In our ongoing investigation into the consequences of a radiological terrorism or nuclear dispersion event, we assessed whether a dose range that is believed to be sub-threshold for the development of lung endpoints results in late pathological changes and, secondarily, whether those late changes affect the lung's ability to respond to subsequent challenge.C57BL/6J mice received total body irradiation (0.5-10 Gy) and were followed for 6-18 months after irradiation. At 12 and 15 months, a subset of mice was exposed to a second challenge (aerosolised lipopolysaccharide [LPS]).Cytokines shown to be upregulated early (hours) following irradiation (interleukin [IL]6, keratinocyte chemoattractant [KC], IL1B, and IL1R2) demonstrated increases in messenger ribose nucleic acid (mRNA) expression at late time points, beginning at nine months. Although persistent, dose-dependent increases in T cell counts were seen, no other overt changes in pathophysiology were observed. Nonetheless, animals that were exposed to a secondary challenge at late time points demonstrated an increased inflammatory cell recruitment and persistence in response relative to controls.We propose that, following doses that elicit little change in pathophysiology, sub-clinical radiation-induced injury increases the lungs' susceptibility to a secondary challenge, possibly through a radiation-induced alteration in the immune defense system.

PubMed ID: 21574903

MeSH Terms: No MeSH terms associated with this publication