Fig. 1: Macrophages rescue cells from ferroptotic death.

a The indicated cell types were treated with the RSL3 for 1 h and then were incubated for 24 h with and without Far-red-labeled THP-1-derived macrophages. Cell survival was determined by flow cytometry after gating out macrophages. Graphs summarize an average of 6, 5, and 4 independent experiments, respectively. Rescue by Fer1 was used as a control. b Cells were treated as in (a) and were co-cultured with monocyte-derived instead of THP-1-derived macrophages. c, d Cell death in (a, b) was determined by LDH release. e Cells were treated with IKE for 1 h and then incubated for 24 h with and without Far-red-labeled THP-1-derived macrophages. Cell survival was determined by flow cytometry after gating out macrophages. f Macrophages rescue cells induced to ferroptosis by GPX4 silencing and Fer1 withdrawal with or without low doses of RSL3. Graphs in (b–f) show an average (±STD) of at least four replicates in each group. Representative of at least three independent experiments is shown. ns: non-significant; *p < 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001.