Fig. 3.

Delayed induction of bystander effects in cells co-cultured with post-irradiation thymocytes. Symbols are the same as those in Fig. 1. (A) Bystander effect of post-irradiation thymocytes on chromosomal aberration induction in co-cultured XRCC4^−/– cells. Aberrations are indicated as net increases. ‘C’ indicates the values in XRCC4^−/– cells co-cultured with nonirradiated thymocytes. (B and C), Abolishment of bystander effects of post-irradiation thymocytes by SOD and catalase in co-cultured XRCC4^−/– (B) or Mutyh^−/– cells (C). Mutant cells were cultured without thymocytes (Control), with post-irradiation thymocytes 13 weeks after irradiation (+ thymocytes) or with post-irradiation thymocytes in the presence of SOD plus catalase (+ SOD + catalase) for 24 h. (D–F), Bystander effects of post-irradiation thymocytes in HCT116 (D), OGG1^−/– (E) and Mth1^−/– cells (F). Cells were co-cultured with control thymocytes or post-irradiation thymocytes at Week 8 for 24 h. (G and H) Abolishment of the bystander effect of post-irradiation thymocytes by complement treatment in XRCC4^−/– (G) and Mutyh^−/– cells (H). The cells were co-cultured with control thymocytes or post-irradiation thymocytes at Week 10. Thymocytes were pre-treated with anti-Thy1.2 antibody and complements (+ complement).