Fig. 8.

Infiltration of effector CD8 T cells promotes a diverse proinflammatory infiltrate within nascent atherogenic foci. A: hyperlipidemic mice received transfer of wild-type (WT) or CD137^−/− Ova-specific CD8 T cells and were immunized with SIINFEKL and agonist anti-CD137 mAb. Thirty days postimmunization (dpi), aortic arches were analyzed by flow cytometry for infiltration of transferred CD8 T cells. B: cells isolated from aortic arch were stimulated for 40 h with phorbol 12-myristate 13-acetate + ionomycin and 5 h with brefeldin A. Intracellular IFNγ analyzed through flow cytometry (gated on total events) and T-cell distribution of WT transfer IFNγ⁺ response (gated on IFNγ⁺ cells). *P = 0.01 by 2-group t-test. C: infiltration of endogenous CD8 T cells that do not express the Ova-specific TCR (Vα2Vβ5) have increased infiltration of the aortic arch 30 dpi when the atherogenic foci is first seeded with WT effector CD8 T cells. Infiltration of endogenous, CD137-sufficient Ova-specific CD8 T cells was not statistically significant. ^nsP = 0.3, ***P = 0.0006 by 2-group t-test. D: CD11c MFI expression from indicated T-cell subsets isolated from aortic arch of mice that received WT Ova-specific CD8 T cells. ^nsP = 0.8, ***P = 0.0005, and ****P < 0.0001 via paired t-tests. E: intracellular cytokine staining after stimulation with media, cytokines (IL-2 + IL-36), or SIINFEKL gated on total events on cells isolated from the aortic arch of mice that received WT or CD137^−/− transfer of CD8 T cells. ^nsP > 0.1, *P = 0.01, and **P = 0.006 by paired t-test. F: cells isolated from the aortic arch 30 dpi secrete IFNγ in response to the cytokine combination of IL-2 + IL-36, but not SIINFEKL cognate antigen restimulation. *P = 0.03 and ^nsP > 0.2 via Wilcoxon matched-pairs test, ##P = 0.001 via Mann-Whitney test; n = 6–7 mice/group for all experiments in this figure.