Cell death through the LTβR is not enhanced by sub-lethal irradiation of colorectal tumor cells.

<p>Cells were incubated on plates coated with 10 µg/ml or 1 µg/ml of anti- LTβR mAb (31G4D8) for 48–72 h. Cell viability was determined by 7-AAD uptake comparing cells treated with 31G4D8 versus cells cultured in medium alone and isotype control mAb. A. As a positive control HT-29 cells were incubated with 31G4D8 in conjunction with 50 units/ml IFN-γ (+IFN- γ), or without (-IFN- γ) as a negative control. B–D. Human tumor cells were mock-irradiated (0 Gy) or irradiated with 5 or 10 Gy and re-cultured for 72 h. SW620 (B), Widr (C) and HCT116 (D) cells were then harvested and incubated on plates coated with 10 µg/ml or 1 µg/ml of 31G4D8 for 48–72 h. Experiments were repeated 3 times with similar results.