The Timing of Stimulation and IL-2 Signaling Regulate Secondary CD8 T Cell Responses
Fig 5
The timing of stimulation regulates IL-2 sensitivity and expression of cell-cycle related proteins.
A) Representative histograms showing the expression of the CD25 molecule on 2° effector Thy1.1 P14 CD8 T cells isolated from the spleens of ‘early’ and ‘late’ groups of mice on indicated days after transfer. Shaded graphs represent isotype control staining and open graphs represent specific Ab staining on gated 2° effector Thy1.1 P14 CD8 T cells. Histograms are concatenated using FlowJo software from 1 of 2 independent experiments displaying equal representation from 3 individual mice. B) Percentage of 2° effector P14 CD8 T cells positive for CD25 on various days after transfer. Data are presented as mean+ SEM of 3 mice per group. C) Log geometric mean fluorescence intensity (gMFI) of CD25+ 2° effector P14 CD8 T cells. Data are presented as mean+ SEM of 3 mice per group. D) Histograms showing the expression of CD25 on 2° effector P14 CD8 T cells isolated from the spleen 5 days after transfer. Shaded graphs represent isotype control staining and open graphs represent staining on gated 2° effector Thy1.1 P14 CD8 T cells. Black numbers indicate the percentage of P14 CD8 T cells positive for CD25 and grey numbers indicate the gMFI of CD25+ P14 CD8 T cells. Histograms are concatenated using FlowJo software from one of two independent experiments displaying equal representation from 4–5 individual mice. E) STAT5-pY694 was measured in 2° effector P14 CD8 T cells in the absence (shaded histograms) or after 15 minutes of IL-2 stimulation (open histograms). F) Protein expression of Foxm1, Cyclin A, and Cyclin B1 in 2° effector (day 7) and 1° M P14 CD8 T cells. All experiments are representative of 2–3 independent experiments. The p values are indicated; ns-not significant.