Growth cone collapse assay approach to examine sensitivity of cell neurons to carbon beams

神経成長円錐の破壊を指標とした神経細胞の炭素線感受性の解析

Al-Jahdari, W. S.*; 鈴木 義行*; 吉田 由香里*; 浜田 信行*; 野田 真永*; 白井 克幸*; 舟山 知夫; 坂下 哲哉; 桜井 英幸*; 小林 泰彦; 中野 隆史*

Al-Jahdari, W. S.*; Suzuki, Yoshiyuki*; Yoshida, Yukari*; Hamada, Nobuyuki*; Noda, Shinei*; Shirai, Katsuyuki*; Funayama, Tomoo; Sakashita, Tetsuya; Sakurai, Hideyuki*; Kobayashi, Yasuhiko; Nakano, Takashi*

The growth cone collapse (GCC) assay has been reported as a useful means of quantifying the effects of various factors on nervous tissue. Here, we used the GCC assay to determine the relative biological effectiveness (RBE) of carbon beams to X-rays on the cell neurons. Dorsal root ganglia (DRG) and sympathetic ganglion chains (SYMP) were isolated from day-16 and day-8 chick embryos and cultured for 20 h. Thereafter, neurons were exposed to graded doses of X-rays, or high-LET C ions. Morphological and apoptotic changes of the neurons were examined quantitatively by GCC and TUNEL assay, respectively. Carbon beams induced GCC and neurite destruction in a time and dose-dependent manner. At 12 h post-irradiation, 20 Gy of carbon beams and 30 Gy of X-rays induced about 65% and 25% apoptosis, respectively. RBE of carbon beams was ranged 3.3-4.6. Carbon beams were 3.3-4.6-fold more effective on neuron cells than X-rays. GCC assay could be beneficial in radiobiological investigations.