Fig. 1.

PI3Kγ or PI3Kδ deletion impairs T cell activation in vivo. a Schematics describing the methodology used in this experiment. RAG ^−/− mice received a BALB/c skin allograft; on day 1 post-transplant, the mice were injected with 6 × 10⁶ CD3⁺CD25⁻ T cells isolated from splenocytes of PI3Kγ ^−/−, PI3Kδ ^D910A/D910A or WT naive mice. b Graft survival in recipients of PI3Kγ ^−/− T cells significantly exceeded that in recipients of control T cells (MST of 17 vs. 10 days, respectively, *p < 0.05, t-test, n = 5/group). c Graft survival in recipients of PI3Kδ ^D910A/D910A T cells significantly exceeded that in recipients of control T cells (MST of 15 vs. 10 days, respectively, *p < 0.05, t-test, n = 5/group). d Representative figures of flow cytometry analysis of splenocytes retrieved from transplanted mice at day 7 post-transplant. Data shows significant decrease in Treg induction in the DLN of PI3Kδ ^D910A/D910A recipients of BALB/c skin and WT controls (*p < 0.05, t-test, n = 3/group). Bar graph represents the percentage of Tregs. e Representative example of FACS staining of CD4⁺ PI3Kδ ^D910A/D910A and WT T cells stimulated with anti-CD3/CD28 Abs in the presence of IL-2 and TGFβ. (Data are representative of three separate experiments, *p < 0.05, t-test, n = 3–4/group). Bar graph represents the percentage of induced Tregs. d, e The graphs show data as mean ± s.e.m. (MST mean survival time; Treg regulatory T cell)