IL-7 and IL-15 complexes augment CD8⁺ T-cell accumulation during contraction. (A) OT-I CD8⁺ T cells (10⁵) were adoptively transferred into B6 mice followed by infection with VSV-OVA. On days 5 through 17 of infection, mice were treated every 48 hours with IL-7 complexes, IL-15 complexes, or vehicle alone as a control. Antigen-specific donor CD8⁺ T cells in the spleens and PBLs were identified by CD45.1 expression and assessed at indicated time points. (B) Triangles represent OT-I CD8⁺ T cells per spleen at day 17. Bar represents the mean. (C) The percentage of donor OT-I cells present among PBLs is shown. Small symbols represent individual mice; larger symbols connected with a line represent the mean. (D) The endogenous response to LM-OVA was assessed with K^b OVAp-bound tetramers. Mice were treated with cytokine complexes from day 7 through day 15 after infection. (E) Triangles represent the number of OVAp-specific CD8⁺ T cells per spleen on day 15 as indicated by tetramer staining. Bar represents the mean. (F) The percentage of tetramer⁺ CD8⁺ T cells present among PBLs is shown. Small symbols represent individual mice; larger symbols connected with a line represent the mean. All data are representative of at least 2 independent experiments.