Annexin V/Propidium Iodide (PI) assay was performed as described previously [82 (link)]. Briefly, cells were trypsinized, pelleted and resuspended in FACS-buffer (10 mM HEPES/NaOH pH 7.4, 140 mM NaCl, 5 mM CaCl2) containing Annexin V-APC (BD Biosciences) or Annexin V-Fluos (BD Biosciences) and PI and measured within 2 h.
EGFP-LC3-mRFP-LC3ΔG [54 (link)] fluorescence was measured on a BD Accuri C6 after the cells were harvested and resuspended PBS. The cells were measured in the FL-1 (EGFP) and FL-3 (mRFP) channels of a BD Accuri C6 and the ratio of EGFP/mRFP was calculated to estimate the autophagic flux.
LysotrackerTM Deep Red (excitation/emission max 647/668 nM; Thermo Fisher) was used according to the manufacturer’s instruction. Briefly, 30 min prior to cell harvesting 25 nM LTDR was added and incubated at 37 °C in the dark. After trypsination, the cells were pelleted and washed twice with PBS and finally resuspended in 50 µL PBS for measurement in the FL-4 channel of a BD Accuri C6.