RT Journal Article SR Electronic T1 Regulatory T Cells Shape the Resident Memory T Cell Response to Virus Infection in the Tissues JF The Journal of Immunology JO J. Immunol. FD American Association of Immunologists SP 683 OP 690 DO 10.4049/jimmunol.1202153 VO 192 IS 2 A1 Graham, Jessica B. A1 Da Costa, Andreia A1 Lund, Jennifer M. YR 2014 UL http://www.jimmunol.org/content/192/2/683.abstract AB Regulatory T cells (Tregs) are well known for their role in dampening the immune responses to self-Ags and, thereby, limiting autoimmunity. However, they also must permit immune responses to occur against foreign infectious agents. Using a mouse model of West Nile virus infection, we examined the role of Tregs in the generation of effector and memory T cell responses in the secondary lymphoid organs, as well as the infected tissues. We found that Treg numbers and activation increased in both the secondary lymphoid organs and CNS postinfection. Using Foxp3DTR knock-in mice, we found that Treg-deficient mice had increased Ag-driven production of IFN-γ from both CD4+ and CD8+ T cells in the spleen and CNS during the effector phase. In mice lacking Tregs, there were greater numbers of short-lived effector CD8+ T cells in the spleen during the peak of the immune response, but the memory CD8+ T cell response was impaired. Specifically, we demonstrate that Treg-dependent production of TGF-β results in increased expression of CD103 on CD8+ T cells, thereby allowing for a large pool of resident memory T cells to be maintained in the brain postinfection.