Culturing HeLa and m-ICcl2 Epithelial Cells

The HeLa (human epithelial cells; CCL‐2, ATCC) and m‐IC_cl2 cell lines (murine small intestinal epithelial cells; Bens et al., 1996 (link)) were cultured as previously described (Di Martino et al., 2019 (link); Fattinger et al., 2020 (link)). Both cell lines were passaged 2–3 times per week. Briefly, HeLa cells were maintained at 37°C and 10% CO₂ in high‐glucose Dulbecco's modified Eagle's medium (DMEM; Gibco), supplemented with 10% heat‐inactivated fetal bovine serum (FBS; Thermo Fisher Scientific) and 100 U/ml PenStrep (Gibco). m‐IC_cl2 cells were maintained at 37°C and 5% CO₂ in DMEM/F12 (Invitrogen) supplemented with 2% heat‐inactivated FBS (Invitrogen), 100 U/ml PenStrep, 5 μg/ml insulin (Invitrogen), 50 nM dexamethasone (Sigma–Aldrich), 60 nM sodium selenite (Sigma–Aldrich), 5 μg/ml bovine apo‐transferrin (Sigma–Aldrich), 1 nM triiodothyronine (Sigma–Aldrich), 60 ng/ml EGF (Sigma–Aldrich), 2 mM glutamine (Invitrogen), 12.5 mM D‐glucose (Sigma–Aldrich), and 20 mM HEPES (Gibco). For infection experiments, antibiotics were omitted and cells were seeded onto the relevant cell plastics 24 h before infection.