Pre-existing intratumoral stem-like CD8+ T-cells drive radiotherapy-induced tumor control

CD8+ T-cells are essential for spontaneous and therapy-induced restriction of tumor progression. Upon radiotherapy, these pre-existing CD8+ T-cells expand rapidly after their initial decline and are essential and sufficient for early tumor control. Stem-like CD8+ T-cells proliferate and differentiate into effector CD8+ T-cells in response to radiotherapy and are thus key determinants of therapy efficacy. Our findings highlight the critical role of intratumoral stem-like CD8+ T-cells in driving radiotherapy-induced anti-tumor immunity. Our study provides deeper insights into the dynamic behavior of CD8+ T-cells and their critical involvement in tumor control following radiotherapy.