Fig. 2.

DGKζ but not DGKα limits the CD8⁺ T cell response to IL-15.

a. Total splenocytes from WT, DGKα and DGKζ-deficient mice were stained with Violet Cell Trace, cultured with IL-2 or IL-15 (72 h) and analyzed by flow cytometry. Left, Violet Cell Trace histogram gated on CD8⁺ T cells. Right, the division index was calculated using FlowJo software. Mean ± SEM, n = 3/genotype and treatment. Bonferroni post-test. b. Total splenocytes from WT or DGKζ-deficient mice were stained and analyzed by flow cytometry. Left, IL-15R histogram gated on CD3⁺ CD8⁺ CD122^hi. Right, quantification. Mean ± SEM, n = 6/genotype. Unpaired t-test with Welch's correction. c. Total splenocytes from WT or DGKζ-deficient mice were cultured (48 h) in anti-CD3-coated plates or with IL-2 or IL-15, then stained and analyzed by flow cytometry. Left, dot plots of IL-2 high affinity receptor (CD122^hiCD25^hi) or IL-15 high affinity receptor (CD122^hiIL15R^hi) gated on CD3⁺ CD8⁺. One representative experiment of two is shown. Right, MFI quantification of CD122, CD25 and IL15R in the CD3⁺ CD8⁺ T cell population. Mean ± SEM, n = 3/genotype and treatment (except IL-15-treated DGKζ^−/− cells, n = 2). Bonferroni post-test.