Phenotype and activation changes in CD8⁺ cells after stimulation by allogeneic DCs with and without anti-IL-15 antibodies. CD8⁺ cells from HIV-infected subjects were either (A) control (10 U/m recombinant human IL-2), (B) polyclonally stimulated by anti-CD3 and anti-CD28 antibodies, (C) cocultured with allogeneic DCs (1:5 DC/CD8⁺ cell ratio), or (D) cocultured with allogeneic DCs in the presence of 10 μg/mL anti-IL-15 antibody for 6 days. CD8⁺ cells were removed and assessed by FACS for activation markers after staining with fluorophore-conjugated antibodies to CD28, CD25, HLA-DR, and CD45RO. Percentages reflect the number of CD8⁺ cells expressing that phenotype marker. Results are representative of 5 separate experiments.