LET and Ion-species dependent bystander effects induced by microbeams

我们研究了低能氦离子束辐照下原发性正常人支气管上皮细胞的旁观者染色体损伤。将未辐照细胞与氦离子辐照细胞一起置于培养皿中，观察到未辐照的旁观者细胞出现旁观者染色体效应。在直接撞击细胞中观察到染色单体类型片段，如染色单体断裂、无中心片段、等染色单体缺失和染色质间交换。另一方面，在旁观者细胞中只观察到染色单体断裂和无中心碎片。有证据表明，单纯染色体损伤发生在旁观者染色体效应中。

We have investigated bystander chromosomal damage in primary normal human bronchial epithelial cells irradiated with low-energy He-ion beams. When the unirradiated cells were kept with He-ion irradiated cells on the dishes, bystander chromosomal effect was observed in the unirradiated bystander cells. Chromatid-type fragments, such as chromatid break, acentric fragment, isochromatid deletion and interchromatin exchange, were observed in the direct hit cells. On the other hand, only chromatid breaks and acentric fragments were observed in the bystander cells. There is evidence that simple chromosomal damage occur in bystander chromosomal effect.