Extended Data Fig. 2: Silencing of CISH and ATP6V1A expression in day 3-activated naïve CD4+ T cells.

a, Naïve CD4+ T cells were transfected with control or CISH siRNA and activated for 3 days (n = 3). Lysosomal acidification was determined by flow cytometry-based analysis of LysoSensor-treated cells. b, Naïve CD4+ T cells from a young and an older individual were co-stained with anti-CISH (green) and anti-ATP6V1A Ab (red). Confocal images representative of three independent experiments are shown. c, Proteasome activity in day 3-activated naïve CD4+ T cells from 6 young and 6 older individuals. d, Naïve CD4+ T cells from 3 young individuals were transfected with control or ATP6V1A siRNA and activated for 3 days. Reduced ATP6V1A protein expression after silencing was confirmed by Western blotting. Data are presented as mean ± s.e.m. Comparison by two-tailed paired t-test (a and d) or two-tailed unpaired t-test (c). *P < 0.05; NS, not significant.