FIG 3.

Anti-CD20 treatment resulted in lower CD8⁺ T cell functional activity. Mice injected with isotype control (control) or anti-CD20 (αCD20) mAb were infected with 5,000 trypomastigotes of T. cruzi strain Tulahuén. Uninfected mice were processed in parallel. Splenic cells were obtained at 20 dpi and analyzed by flow cytometry. (A) Bar graphs indicate the frequency ± SD of polyfunctional CD8⁺ T cells upon parasite antigen stimulation. Reference data corresponding to the different populations (IFN-γ⁺ TNF⁺ CD107a⁺ triple positive, IFN-γ⁺ TNF⁺ or IFN-γ⁺ CD107a⁺ double positive, and IFN-γ⁺ single positive CD8⁺ T cells) are indicated. (B) Representative histograms and statistical analysis of T-bet expression in total and Tskb20/K^b+ CD8⁺ T cells from infected control (empty solid line) or anti-CD20-treated (empty dashed line) mice or uninfected mice (gray-filled solid line). (C) (Left) Representative dot plots of the frequency of transferred antigen-pulsed and unpulsed cells in the spleen of uninfected (top right) and infected (bottom left) control mice or anti-CD20-treated mice (bottom right) at 20 dpi. (Right) Statistical analysis of percentage of specific lysis in infected control (white bars) or anti-CD20-treated (black bars) mice. Results are representative of three (A and B) and two (C) independent experiments with 5 to 6 (A and B) or 4 to 5 (C) mice per group each. P values were calculated with the two-tailed t test.