CD4 + T cells were cultured for 3 d on plate-bound anti-CD3epsilon and anti-CD28 antibodies, with ATRi or vehicle only added to cultures for the final 36 h. Graph showing percentage of CD4 + cells in G2/M phase (EdU - , 4n), gating as in Supplementary Fig. 4e ( n = 6). WNKi, WNK inhibitor (WNK463); SRCi, SRC inhibitor (Dasatinib); AQP3i, AQP3 inhibitor (DFP00173); ATRi, ATR inhibitor (AZD6738). Each point represents a different mouse; columns show median. Data pooled from 2 ( a-d, g, h) or 3 ( e ) independent experiments or from 1 experiment representative of 5 ( f ). Statistical analysis carried out using the 2-sided Mann-Whitney U test. * 0.01 < p < 0.05; ** 0.001 < p < 0.01, *** 0.0001 < p < 0.001, **** p < 0.0001. Source data are provided as a Source Data file.