Human Epithelial Teratocarcinoma Cells (P3): Radiobiological Characterization, DNA Damage, and Comparison with Other Rodent and Human Cell Lines

Survival parameters and immediate DNA damage induced by⁶⁰ Co γ rays, 50-kVp X rays, and Janus fission-spectrum neutrons in human epithelial P3 cells (derived from an embryonic teratocarcinoma) are compared with those for Chinese hamster lung V79 cells. DNA damage caused by X and γ irradiation, measured by alkaline elution methods, is the same in both cell types, whereas the P3 cells are about two times more sensitive (as measured by D₀ ratios of the final survival curve slope) to the lethal effects of these radiations than are the V79 cells. Human P3 cells are also more sensitive to the lethal effects of fission-spectrum neutrons than V79 cells. Survival experiments with split radiation doses and hypertonic salt treatment indicate that both P3 cells and V79 cells can recover from radiation-induced damage efficiently.