The relative biological effectiveness (RBE) based on the induction of dicentrics in any cell type is principally an important information for the increasing application of high-LET radiation in cancer therapy. Since the standard system of human lymphocytes for measuring dicentrics are not compatible with our microbeam irradiation setup where attaching cells are essential, we used human-hamster hybrid AL cells which do attach on foils and fulfil the special experimental requirement for microbeam irradiations. In this work, the dose-response of AL cells to photons of different energy, 70 and 200 kV X-rays and 60Co γ-rays, is characterized and compared to human lymphocytes. The total number of induced dicentrics in AL cells is approximately one order of magnitude smaller. Despite the smaller α and β parameters of the measured linear-quadratic dose-response relationship, the α/β-ratio versus photon energy dependence is identical within the accuracy of measurement for AL cells and human lymphocytes. Thus, the influence of the reference radiation used for RBE determination is the same. For therapy relevant doses of 2 Gy (60Co equivalent), the difference in RBE is around 20% only. These findings indicate that the biological effectiveness in AL cells can give important information for human cells, especially for studies where attaching cells are essential.
Schmid TE, Greubel C, Dollinger G, Schmid E.
Download Paper
Xstrahl to Feature SmART-RAD at RRS 2024 in Tucson, AZ
Xstrahl, the leader in preclinical radiation research systems, will demonstrate SmART-RAD at the 70th Annual Meeting of the Radiation Research Society (RRS) at the Westin La Paloma Resort & Spa, in Tucson, AZ, Sept. 15-18.