Fig 1: IL-2R signalling is impaired in autophagy-deficient CD4+ T cells.a Schematic overview of how excessive interleukin-7 receptor-a (IL-7Ra) may lead to impaired T cell proliferation. During T cell activation, the interleukin-2 receptor-a (IL-2Ra) is upregulated on the cell surface, while surface IL-7Ra is decreased. In T-Atg7-/- CD4+ T cells, excessive IL-7Ra sequestrates the common gamma chain (?c), a key subunit of both IL-7R and IL-2R, and abrogates the downstream IL-2R signalling which is crucial for the expansion of the effector population. b Experimental set-up: naïve CD4+ T cells from either wild-type or T-Atg7-/- mice were activated with anti-CD3/CD28 Dynabeads for 24 h, followed by treatment with murine IL-2 for 15 min. Phosphorylated Stat5 (pStat5) level was measured by flow cytometry. c Histograms (left) of pStat5 level in activated CD4+ T cells from wild-type or T-Atg7-/- mice, stimulated with different doses of murine IL-2. Bar graph (right) depicts the ratio of increase in p-Stat5 signal in response to 20 ng ml-1 murine IL-2 (pStat5IL-2 – pStat5ctrl) to the basal level (pStat5ctrl), determined from two independent experiments, n = 5 mice per group. d TIRF imaging (left) of IL-7Ra, IL-2Ra and ?c at the immunological synapse. Naive CD4+ T cells activated for 24 h were exposed to supported lipid bilayers containing ICAM1 and anti-CD3 proteins, then fixed after a 10-min incubation with 50 U ml-1 murine IL-2. Cytokine receptors were stained for imaging. Square insets show magnification of the co-localisation events. Bar graph (right) shows Pearson’s correlation coefficient between the IL-2Ra and ?c, n = 13 cells for wild-type group, n = 20 cells for T-Atg7-/- group. e Confocal imaging of IL-7Ra and ?c at the surface of activated CD4+ T cells (with high CD25 expression). Bar graph (right) shows Pearson’s correlation coefficient between the IL-7Ra and ?c at the cell surface, n = 23 cells per group. All quantitative analyses are representative of three independent experiments. All data are represented as mean ± SEM with unpaired two-tailed Student’s t test. Exact p values are depicted in the figure. Source data are provided as a Source Data file.