FIG 8.

Recombinant IL-6 did not modify the magnitude and effector phenotype of the CD8⁺ T cell response observed in infected anti-CD20-treated mice. Mice infected with 5,000 trypomastigotes of T. cruzi strain Tulahuén were injected with isotype control (control; white bars) or anti-CD20 mAb 8 days before infection. Infected mice injected with anti-CD20 mAb were also injected with PBS (αCD20, black bars) or rIL-6 (αCD20 + rIL-6, gray bars) at 12, 14, 16, and 18 dpi. The spleens of the different groups of mice were obtained at 20 dpi. (A) (Top panels) Representative dot plot showing the percentage of total and TSKB20/K^b+ CD8⁺ T cells, gated on lymphoid cells. (Bottom panels) Statistical analysis of the means ± SD of the percentages and number of indicated cells. (B) Statistical analysis of the number of SLEC and MPEC in total and Tskb20/K^b+-specific CD8⁺ T cells. (C) Statistical analysis of total IFN-γ⁺ CD8⁺ T cell frequency of splenic cells stimulated with PMA plus ionomycin (Polyclonal stimulation) or with Tskb20 (Ag-specific stimulation) after 5 h of culture. (D) Statistical analysis of T-bet expression on total and TSKB20/K^b+ CD8⁺ T cells. Results are representative of two independent experiments with 4 to 6 mice per group each. P values were calculated with one-way ANOVA followed by Bonferroni’s posttest.