Impact of MyD88 or Ly49H deficiencies on antiviral CD8 T cell responses.

<p>(A-C) Analysis of antiviral CD8 T cell effector functions. (A) <i>In vivo</i> cytotoxicity, <i>ex vivo</i> IFN-γ production and Granzyme B expression by splenic CD8 T cells from BALB/c-Ly49H⁺, BALB/c-Ly49H⁺ MyD88^-/-, BALB/c and BALB/c MyD88^-/- mice at d0 and 6 post infection. Data (mean ± SEM) are shown from 3 pooled independent experiments each with 2 or 3 mice per group. (B-C) Impact of CD8 T cell depletion on disease in BALB/c and BALB/c MyD88^-/- mice. Mice were depleted of CD8 T cells and infected with 2.5x10³ pfu MCMV (B) or with 8x10³ pfu MCMV (C). Splenic viral titers were measured at d6 post infection (B) or mortality was monitored daily (C). For B, data (mean±SEM) are represented from 2 pooled independent experiments each with 2 to 4 mice per group. For C, data show the percent survival from 2 pooled independent experiments each with 3 to 5 mice per group, n represents the total number of mice per group. (D) Enumeration of total (left panel) and anti-IE-1 (right panel) CD8 T cells in the spleens of d5 MCMV-infected mice. Results (mean±SEM) are shown from 4 pooled independent experiments each with 3 mice per group. (E) Immunohistological analysis of tissue damage to the spleen in d4 MCMV infected mice. Mice were infected with 10⁴ pfu MCMV. Spleen were harvested at d4 and stained to evaluate the integrity of the T cell zone as assessed by examining its marginal zone boundary (CD169) and its T cell (CD3) and B cell (B220) zones. Results are shown for one representative mouse per experimental group from 3 independent experiments each with 3 mice per group.