Cutting Edge: Batf3 Expression by CD8 T Cells Critically Regulates the Development of Memory Populations.

The basic leucine zipper transcription factor ATF-like 3 (BATF3) is required for the development of conventional type 1 dendritic cells that are essential for cross-presentation and CD8 T cell-mediated immunity against intracellular pathogens and tumors. However, whether BATF3 intrinsically regulates CD8 T cell responses is not well studied. In this article, we report a role for cell-intrinsic Batf3 expression in regulating the establishment of circulating and resident memory T cells after foodborne Listeria monocytogenes infection of mice. Consistent with other studies, Batf3 expression by CD8 T cells was dispensable for the primary response. However, Batf3 -/- T cells underwent increased apoptosis during contraction to contribute to a substantially reduced memory population. Batf3 -/- memory cells had an impaired ability to mount a robust recall response but remained functional. These findings reveal a cell-intrinsic role of Batf3 in regulating CD8 T cell memory development.