Figure 5.

(a) Special procedures to study the rescue effect by physically separating the rescue signals (represented by blue arrows) from the bystander signals (represented by pink arrows) through the preparation of the CM (pink). The irradiated cell (green) sending out the bystander signals was different from the irradiated cell (orange) receiving the rescue signals. Preparation and use of the CM involved three separate dishes. The first was the “IR dish” to hold the cells for alpha-particle irradiation with partnered unirradiated cells to allow co-culture. The second was the “CM dish” to hold the unirradiated cells transferred from the IR dish to create the CM. The third was the “Recipient dish” to hold the HeLa cells for alpha-particle irradiation, which were immersed in the CM harvested from the CM dish; (b) Setup to study the rescue effect without physically separating the rescue signals from the bystander signals. The irradiated cell (cyan) receiving the rescue signals was the same as the irradiated cell sending out the bystander signals.