Multimodal approach for ionizing radiation damage investigation

Abstract

The new, leading edge laboratory has been established and put into routine operation. The laboratory is focused on multimodal studies of the cellular response to ionizing radiation and provides support and research facilities for the Bronowice Cyclotron Centre. Spectroscopic imaging of cells and tissues (examining in particular the internal structure of cells, the cytoskeleton organization, cells’ mechanical and biochemical properties), as well as research at the molecular level, has been applied in research for the purpose of searching new strategies of prevention and therapies of cancer and other pathologies and in fundamental research in the field of structural and vibrational analysis of condensed matter. The multimodal approach, illustrating the full laboratory potential, has been applied to radiation effect studies of transitional cells – human bladder carcinoma cells (T24 cell line). Cells were irradiated with three X-ray radiation doses: 1 Gy, 3 Gy, and 10 Gy and subsequently studied using all instruments of the new laboratory. The presented results demonstrated that the AFM elasticity measurements can be applied to quantitatively estimate alterations induced upon Xray irradiation at the single cell level. A combination of AFM and InfraRed Spectroscopy (NanoIR2 setup) was successful in characterization molecular changes occurring in the nuclear environment following cellular irradiation. Particularly useful information acquired was the observation of changes in distribution of macromolecules with a spatial resolution at the level of the single organelle. The observed changes correlate with radiation dose and thus may become a tool for studying the biological effects of radiation exposure. The application of Raman microspectroscopy for radiation-induced damage investigations provided detection of such spectral changes as strand breaks, base unstacking, and DNA conformational transformations. These studies give crucial information about the damage associated with irradiation and cellular response for radiation dose at single cell level. Moreover, Raman spectroscopy provides possibility to investigate structural changes present within the same sample. Complementary UV–VIS technique, on the basis of γ-H2AX test, delivered quantitative data of radiation damage, manifesting in presence of double strand breaks in DNA in 1st and 2nd day of culture (1 hour and 24 hours after irradiation).