Fig 1.

Early but not delayed CD4 T cell depletion affects priming and expansion of peripheral naïve CD8 T cells. CD4 T cell were depleted either at −2, 0, and +2 days p.i. (A) or at 4 and 6 days p.i. (B). Frequencies of CLN-derived IFN-γ-secreting CD8 T cells at days 5 and 7 p.i. were determined by flow cytometry after stimulation with S510 peptide. Data are representative of results of two independent experiments and expressed as the numbers of IFN-γ⁺ per 10⁶ CD8⁺ T cells. Statistically significant differences between the control and CD4 T cell-depleted samples are indicated as follows: **, P < 0.005.