IL-27 receptor signaling enhances the number of antiviral CD4 T cells despite promoting MCMV persistence.

<p>WT and <i>Il27ra</i>^<i>-/-</i> mice were infected with 1*10⁴ PFU MCMV and MCMV-specific CD4 T cell responses were monitored. Representative dotplot showing the gating strategy based on combined expression of CD11a and CD49d and CD11a⁺CD49d⁺ CD4 T cells enumerated in the blood at day 7 p.i. (A) and spleen at day 40 p.i. (B). M09_133-147 specific CD4 T cells were quantified using peptide-MHCII tetramer enrichment in pooled spleens at day 40 p.i. (C). (D-E) WT:<i>Il27ra</i>^<i>-/-</i> chimeric mice were infected with 1*10⁴ PFU MCMV and the proportions of CD11a^-CD49d^- versus CD11a⁺CD49d⁺ CD4 T cells residing within the WT and <i>Il27ra</i>^<i>-/-</i> compartment were analyzed in the blood at day 7 p.i. (D) and in the spleen at day 40 p.i.(E). (F) Viral titers were determined in the salivary glands (SG) of WT and <i>Il27ra</i>^<i>-/-</i> mice at day 21 and day 40 p.i. (A-B) one representative of 3 independent experiments with n = 4–5 mice per group. (C) one representative of 2 independent experiments with pooled samples of n = 4–5 mice per group. (D-E) one representative of 2 independent experiments with n = 4–5 mice per group (F) Pooled data of 2–3 independent experiments with n = 4–5 mice per group. * p < 0.05, *** p < 0.001, **** p < 0.0001.