title: Radiobiological influence of megavoltage electron pulses of ultra-high pulse dose rate on normal tissue cells.
abstract: Regarding the long-term goal to develop and establish laser-based particle accelerators for a future radiotherapeutic treatment of cancer, the radiobiological consequences of the characteristic short intense particle pulses with ultra-high peak dose rate, but low repetition rate of laser-driven beams have to be investigated. This work presents in vitro experiments performed at the radiation source ELBE (Electron Linac for beams with high Brilliance and low Emittance). This accelerator delivered 20-MeV electron pulses with ultra-high pulse dose rate of 10(10) Gy/min either at the low pulse frequency analogue to previous cell experiments with laser-driven electrons or at high frequency for minimizing the prolonged dose delivery and to perform comparison irradiation with a quasi-continuous electron beam analogue to a clinically used linear accelerator. The influence of the different electron beam pulse structures on the radiobiological response of the normal tissue cell line 184A1 and two primary fibroblasts was investigated regarding clonogenic survival and the number of DNA double-strand breaks that remain 24 h after irradiation. Thereby, no considerable differences in radiation response were revealed both for biological endpoints and for all probed cell cultures. These results provide evidence that the radiobiological effectiveness of the pulsed electron beams is not affected by the ultra-high pulse dose rates alone.
authors.affiliation: OncoRay - National Centre for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, PF 41, 01307, Dresden, Germany.|Institute of Radiation Physics, Helmholtz-Zentrum Dresden - Rossendorf (HZDR), Bautzner Landstraße 400, P.O. Box 510119, 01314, Dresden, Germany.|Menarini - Von Heyden GmbH, Leipziger Straße 7 - 13, 01097, Dresden, Germany.
authors.forename: Lydia
authors.initials: L
authors.lastname: Laschinsky
authors.affiliation: OncoRay - National Centre for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, PF 41, 01307, Dresden, Germany.
authors.forename: Leonhard
authors.initials: L
authors.lastname: Karsch
authors.affiliation: Institute of Radiation Physics, Helmholtz-Zentrum Dresden - Rossendorf (HZDR), Bautzner Landstraße 400, P.O. Box 510119, 01314, Dresden, Germany.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Leßmann
authors.affiliation: OncoRay - National Centre for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, PF 41, 01307, Dresden, Germany.|Institute of Radiation Physics, Helmholtz-Zentrum Dresden - Rossendorf (HZDR), Bautzner Landstraße 400, P.O. Box 510119, 01314, Dresden, Germany.|Quintiles GmbH, Hugenottenallee 167, 63263, Neu-Isenburg, Germany.
authors.forename: Melanie
authors.initials: M
authors.lastname: Oppelt
authors.affiliation: OncoRay - National Centre for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, PF 41, 01307, Dresden, Germany.|Institute of Radiation Physics, Helmholtz-Zentrum Dresden - Rossendorf (HZDR), Bautzner Landstraße 400, P.O. Box 510119, 01314, Dresden, Germany.
authors.forename: Jörg
authors.initials: J
authors.lastname: Pawelke
authors.affiliation: OncoRay - National Centre for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, PF 41, 01307, Dresden, Germany.|Institute of Radiation Physics, Helmholtz-Zentrum Dresden - Rossendorf (HZDR), Bautzner Landstraße 400, P.O. Box 510119, 01314, Dresden, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Richter
authors.affiliation: OncoRay - National Centre for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, PF 41, 01307, Dresden, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Schürer
authors.affiliation: Institute of Radiation Physics, Helmholtz-Zentrum Dresden - Rossendorf (HZDR), Bautzner Landstraße 400, P.O. Box 510119, 01314, Dresden, Germany. E.Beyreuther@hzdr.de.
authors.forename: Elke
authors.initials: E
authors.lastname: Beyreuther
mesh_terms: D002460:Cell Line; D053903:DNA Breaks, Double-Stranded; D004583:Electrons; D005347:Fibroblasts / Q000378:metabolism / Q000528:radiation effects; D006801:Humans; D007834:Lasers; D010315:Particle Accelerators; D011829:Radiation Dosage; D012062:Relative Biological Effectiveness
keywords: Cell response to electron beams; Laser-driven radiotherapy; Normal tissue cell culture; Pulsed irradiation; Ultra-high pulse dose rate