Figure 2. IL-10 producing CD8⁺ and CD4⁺ T cells are Type 1 effectors.

BALB/c mice were infected with influenza. CD8⁺ (a–c) or CD4⁺ (e, f) cells from lungs of uninfected mice or mice 7 days p.i. with influenza were restimulated with influenza infected BMDC and the expression of T-bet (a, e), Foxp-3 (b, f) and a panel of effector or activation molecules (c) in uninfected lung CD8⁺ or CD4⁺ T cells (control) or IL-10 positive CD8⁺ or CD4⁺ T cells (IL-10⁺), IFN-γ single positive CD8⁺ or CD4⁺ T cells (IFN-γ SP), IL-10 and IFN-γ double negative CD8⁺ or CD4⁺ T cells (DN) from infected lungs were measured by ICS. Gray line: isotype control Ab staining. Numbers are MFI (a, e) or percentages of Foxp-3-positive cells in the gates within the total population (b, f). (d, g) Uninfected mice (control) and mice 6 days p.i. were injected with BrdU. 2 h later, mice were sacrificed and lung cells were restimulated with influenza-infected BMDC. The percentages of BrdU⁺ cells in CD8⁺ (d) or CD4⁺ (g) cells of uninfected lung (control) and the IL-10⁺, IFN-γ single positive (IFN-γ SP) and IL-10⁻ IFN-γ⁻ (DN) T cells of 6 days p.i. lung are depicted.