DOI 10.1393/ncc/i2008-10280-x IL NUOVO CIMENTO Vol. 31 C, N. 1 Gennaio-Febbraio 2008 Status report of a systematic investigation on low-dose ionizing radiation effects in mammalian cells R. Cherubini( 1 )( ∗ ), V. De Nadal( 1 ), S. Gerardi( 1 ), D. Guryev( 1 )( ∗∗ ), A. Antoccia( 2 ), F. Berardinelli( 2 ), A. Sgura( 2 ) and C. Tanzarella( 2 ) ( 1 ) INFN, Laboratori Nazionali di Legnaro - Legnaro (Padova), Italy ( 2 ) INFN, Sezione di Roma 3 and Dipartimento di Biologia, Universit` a di Roma 3 Rome, Italy (ricevuto l’ 11 Giugno 2008; pubblicato online il 17 Settembre 2008) Summary. — In the last 15 years a growing interest in the biological effects induced by low doses of ionizing radiation has arisen in the scientific community, due to an increasing number of experimental evidences showing a plethora of non-linear ef- fects occurring after low-dose irradiations. In particular, hyper-radiosensitivity and induced radioresistance (HRS/IRR) have been reported after exposure to low- and high-LET radiation, in human (normal and tumoural) and other mammalian cells in vitro. In this framework, Chinese hamster V79 cells, human primary fibroblasts (HFFF2) and murine embryonic fibroblasts (MEFs) were irradiated with broad- beams of protons in the dose range 0.1–5.0 Gy and at 1 Gy/min dose-rate. Cellular response has been evaluated in terms of cell survival, micronuclei induction, chro- mosomal aberrations and telomere length alterations. For comparison purpose, the same end-points were studied after X/γ-rays irradiation. PACS 87.53.-j – Effects of ionizing radiation on biological systems. PACS 87.53.Ay – Biophysical mechanisms of interaction. PACS 87.53.Bn – Dosimetry/exposure assessment. PACS 87.18.Gh – Cell-cell communication; collective behavior of motile cells. 1. – Introduction In the last 15 years a continuously growing interest in the biological effects induced by low doses of ionizing radiation, of relevance to environmental and occupational radiation exposure, has arisen in the scientific community. This is because recent experimental evidences in vitro have shown the presence of a plethora of phenomena occurring after low-dose irradiation (including hypersensitivity ( ∗ ) E-mail: roberto.cherubini@lnl.infn.it ( ∗∗ ) EC RTN-MC “Cellion project” fellow. c  Societ` a Italiana di Fisica 57 CORE Metadata, citation and similar papers at core.ac.uk Provided by Scientific Open-access Literature Archive and Repository