Fig. 5. Polyamine supplementation and autophagy induction modulate cellular metabolism and limit SARS-CoV-2 growth in primary human lung cells and intestinal organoids.

a Analysis and regulation of significantly altered pathways of SARS-CoV-2-infected VeroFM cells (24 h p.i.) upon treatment with spermine (spm, 100 µM, thin outlined circles) or niclosamide (nic, 10 µM, solid outlined circles). Analysis was done as described in Fig. 1 (n = 4 biological independent replicates per group, one experiment). All p-values were determined by a two-way ANOVA and Tukey´s post hoc test. FDRs were adjusted using the Benjamini-Hochberg method. b Primary human airway epithelial cells (n = 6, from two independent experiments with n = 3) were infected with SARS-CoV-2 (MOI = 0.1) and treated with spm, nic, or vehicle as mentioned in a for 24 h and 48 h, respectively. P-values were determined by two-way ANOVA, Dunnett’s, mean with SEM. c Human intestinal organoids (n = 8, from two independent experiments with n = 4) were infected with SARS-CoV-2 (MOI = 0.05) and treated with spm, nic, or vehicle as above for 48 and 72 h, respectively. Data are presented as fold change PFU/ml or GE/ml. Two-way ANOVA, Dunnett’s, mean with SEM was used for p-value calculation. Technical outliers were removed resulting in n = 7 for spm, 72 h p.i. (PFU/ml), and nic, 48 h p.i. (GE/ml) as well as n = 6 for veh, 72 h p.i. (GE/ml). d VeroFM cells were infected with SARS-CoV-2 (MOI = 0.0005) and treated with increasing concentrations of spermidine (spd), spm, MK-2206, and nic (n = 3 biological replicates per concentration from one experiment, mean with SEM) to calculate the 50% inhibitory concentration (IC₅₀). Technical outliers were removed resulting in n = 2 for nic, 0.046 µM, 48 h p.i. (PFU/ml). Limit of detection (LOD) of the plaque assay was 50. Data are presented as percentages of the negative control (see Supplementary Fig. 14 (raw data) and Fig. 10 (cytotoxicity assays)). p ≤ 0.05 (*), p ≤ 0.01 (**), p ≤ 0.001 (***), p ≤ 0.0001 (****), p > 0.05 (not significant, ns). Abbreviations: GE, genome equivalents; LOD, limit of detection; met., metabolism; nic, niclosamide; PFU, plaque-forming units; spd, spermidine; spm, spermine; veh, vehicle.