Figure 1.
Experimental set up for bystander experiments.
Figure 2.
Assessment by H2AX immunostaining of DNA double strand breaks in chronic 24-irradiated ZF4 cells.
Figure 3.
Exposure of ZF4 cells to gamma irradiation induces bystander responses in non-irradiated cells.
A. Kinetics of γ-H2AX foci disappearance on 70 mGy/d gamma-irradiated ZF4 cells, respectively. B. Kinetics of γ-H2AX foci disappearance on 550 mGy/d gamma-irradiated ZF4 cells, respectively. Each data plot represents the mean+/−SE (n = 6) of at least 3 independent experiments.
Figure 4.
Exposure of ZF4 cells to gamma irradiation induces micronuclei in bystander cells.
Micronuclei number was assessed on 1,000 cells stained with DAPI.
Figure 5.
Gamma irradiation affects global methylation in irradiation and bystander cells.
Methylation was measured by HPLC-MS. 3 μg of total DNA from irradiated and bystander cells were used. *p-value <0.5.
Figure 6.
Experimental set up for radioadaptation experiments.
Figure 7.
Early bystander effect leads to the radioprotection of non-irradiated cells.
Pre-irradiated cells (called adaptation cells) were placed near non-irradiated cells (called bystander cells) for 1 hour. This incubation was followed by a second irradiation of adaptation and bystander cells for 19 hours. Assessment of γ-H2AX foci number was done on adaptation, bystander and control ZF4 cells 24 h after irradiation with gamma rays at a dose rate of either 70 mGy/d and 550 mGy/d. The difference in the formation of γ-H2AX foci was significant (***p-value <0.001, Student Test).