Regulation of Antigen-Specific CD8 + T Cell Homeostasis by Perforin and Interferon-γ

Abstract

T cell memory depends on factors that regulate expansion and death of these cells after antigenic stimulation. Mice deficient in perforin and interferon-γ (IFN-γ) exhibited increased expansion, altered immunodominance, and decreased death of antigen-specific CD8 + T cells after infection with an attenuated strain of Listeria monocytogenes , which was cleared from these mice. Expansion of CD8 + T cells was controlled by perforin, whereas IFN-γ regulated immunodominance and the death phase. Thus, perforin and IFN-γ regulate distinct elements of CD8 + T cell homeostasis independently of their role as antimicrobial effector molecules.