Section of Toxicology and Biomedical Sciences, ENEA CR Casaccia, 00123 Rome, Italy.
Radiat Res. 2010 Jun;173(6):779-88. doi: 10.1667/RR1835.1.
The aim of this investigation was to explore whether the occurrence and the magnitude of radiation-induced, medium-mediated bystander effects could be influenced by the time of transfer of secreted bystander factors. HaCaT cells were exposed to 0.1 and 1.0 Gy of gamma radiation. These doses did not induce a significant reduction in the clonogenic survival of irradiated cells compared to controls. Bystander cells either were co-cultured with irradiated cells or received medium from irradiated cells. The bystander effects analyzed included end points related to survival (clonogenic potential and cell proliferation) and DNA damage (micronucleus induction and gamma-H2AX formation). The bystander effects we investigated either were lacking or varied from potentially protective to detrimental responses in relation to the dose of radiation and the time between irradiation of donor cells and bystander exposure. Our results suggest that the experimental time schedule is important for both the occurrence and the detection of bystander effects in vitro.
本研究旨在探讨分泌的旁观者因子转移时间是否会影响辐射诱导的、介质介导的旁观者效应的发生和程度。HaCaT 细胞接受 0.1 和 1.0 Gy 的γ射线照射。与对照组相比，这些剂量并未导致受照射细胞的集落形成存活能力显著降低。旁观者细胞与照射细胞共培养或接受照射细胞的培养基。分析的旁观者效应包括与存活（集落形成潜力和细胞增殖）和 DNA 损伤（微核诱导和 γ-H2AX 形成）相关的终点。我们研究的旁观者效应要么缺失，要么从潜在的保护反应到有害反应，这与供体细胞照射和旁观者暴露之间的剂量有关。我们的结果表明，实验时间安排对于体外旁观者效应的发生和检测都很重要。
