Vaccine-induced CD8+ T cells eliminate tumors by a two-staged attack.

Data presented here demonstrate that vaccine-induced CD8(+) T cells can eliminate their specific tumor-target with a two-staged attack. First, they release interferon-gamma that results in growth arrest of the tumor cells via induction of antiangiogenic mediators. Then, during the latter stages of the immune response, CD8(+) effector T cells eradicate the remaining tumor cells through perforin-mediated lysis. A combination of these two mechanisms is highly effective in the described model, while either pathway alone fails to completely achieve tumor rejection.