Proteomic profiling to identify potential biomarkers of alpha-particle radiation exposure in human lung epithelial cells

Abstract

Of the radiation types, alpha-(α) particles are of particular interest as they are an environmental concern, predominately due to inhalation of radon and its daughter progeny. Furthermore, α-particle emitters like Americium-241, Plutonium-238 and Polonium-210 have been identified as probable isotopes to be used in radiological dispersal devices. Thus, the identification of potential biomarkers to α-particle radiation exposure would be useful for the development of field deployable bioassays which could be used for human risk assessment and public health protection. Human lung cells were exposed to α-particle radiation and assessed for modulations in protein expression using two-dimensional gel electrophoresis (2D-GE). Concurrently, cell culture supernatants were analyzed for cytokine secretion using a multiplex-27 bead array assay. Cell culture supernatants assessed for cytokine secretion expressed 8 statistically significant cytokines following α-particle exposure, among which VEGF was confirmed to be dose-responsive and not modulated in X-irradiated cells. Analysis of whole cell lysates using 2-D gel electrophoresis showed 15 upregulated and 1 downregulated protein spot, of which 4 were identified by mass spectrometry. These data suggest that α-particle exposure results in the alterations in expression-levels of specific proteins which may be potential biomarkers used further for the development of fast and reliable bioassays.