Detection and observation of oxidative damage for the improvement of high-LET radiation therapy

为了可视化半影区的分布，离子径迹周围的低LET区域，我们开发了一种方法来成像8-OHdG的分布，8-OHdG是OH自由基与鸟嘌呤残基反应的辐射产物，使用1)小鼠脑组织、2)人A549细胞和3)DNA薄膜的免疫荧光染色。阳性染色明显，特别是在小鼠大脑周围区域和小脑浦肯野细胞。细胞核的免疫荧光染色是在小到5Gy时检测到的，在那里我们可以区分每一个传入的颗粒。DNA膜具有不溶于水的特性，特别考虑到其均匀性，并通过Fenton反应产生OH自由基处理，成功地染色了均匀形成的8-OHdG。

In order to visualize the distribution of a penumbra, a low LET region around ion tracks, we have developed the methods to image the distribution of 8-OHdG, a radiation product resulting from the reaction of OH radicals with guanine residue, using an immunofluorescence staining for 1) mouse brain tissue, 2) human A549 cells, and 3) DNA thin film. Positive stains were evident particularly in the peripheral region of the cerebrum and in Purkinje cells of the cerebellum in mice. The immunofluorescence staining of cell nuclei was detected at a dose as small as 5 Gy where we can distinguish each incoming particle. DNA film with an insoluble property to water was developed with special reference to the uniformity, and the treatment with Fenton reaction to generate OH radicals resulted in the successful staining of uniformly formed 8-OHdG.