Role of cell cycle regulator p19ARF in regulating T cell responses

Although it is well established that the processes of cellular proliferation and apoptosis are linked, the role of cell cycle regulators in T cell responses in vivo is not well understood. In recent years, tumor suppressor molecule p19ARF has emerged as a key cell cycle regulator important in cellular apoptosis against strong mitogenic stimuli. In this study, we compared the antigen-specific T cell responses between wild type (+/+) and p19ARF-deficient (p19−/−) mice following an acute infection with lymphocytic choriomeningitis virus (LCMV). p19−/− mice mounted a potent CD8 T cell response and the magnitude of expansion of LCMV-specific CD8 T cells was comparable to that of +/+ mice. Further, the clonal downsizing of the expanded virus-specific CD8 T cells and establishment of long-term T cell memory were minimally affected by p19ARF deficiency. Therefore, p19ARF function is not essential to regulate T cell responses following an acute viral infection.