Antigen-specific KLRG1^hiCD8⁺ T cells are resistant to cytokine-mediated proliferation in vivo. (A) Mice were infected with VSV-OVA and treated with cytokine complexes as outlined in Figure 1A. Mice were pulsed with BrdU from days 9 to 12 of infection. On day 12, BrdU incorporation in either KLRG1^lo or KLRG1^hi donor CD8⁺ splenocytes was determined by flow cytometry. (B) OT-I T cells (10⁵) were adoptively transferred into B6 followed by infection with LM-OVA. On day 10 of infection, spleens were harvested and KLRG1^lo and KLRG1^hi donor OT-I CD8⁺ T cells were isolated by cell sorting, labeled with CFSE, and transferred into secondary B6 recipients. Mice were then treated for 6 days with cytokine complexes or vehicle control, and CFSE dilution among donor splenocytes assessed by flow cytometry. (C) Same as in panel B, except that cells were not labeled with CFSE. All data are representative of 2 independent experiments.