Figure 1.

Inhibitory effects of CsA and ALV in different human infection models. (A) Illustration of phBEC infection with HCoV-229E, created with biorender.com. (B) RT-qPCR results of (for 72 h) HCoV-229E infected (MOI = 4) phBECs (n = 3, independent donors) with and without pretreatment in presence of compound CsA and ALV at 10 µM, given as fold changes of intracellular (IC) and supernatant (SN) viral transcript relative to the infection control (inf. contr.), HCoV-229E-infected phBECs treated with the vehicle DMSO (normalized to 1 for both IC and SN). Intracellular: Normalized to the housekeeping gene DEAH-Box Helicase 8 (DHX8). The symbols each represent an independent donor (circles = donor 1; squares = donor 2; triangles = donor 3). For statistical analysis, a paired two-tailed t-test was used and absolute p-values are given for p <0.05. (C) Cell viability was assessed in the absence of virus by the LDH assay after 48 h pretreatment plus 72 h mock infection in percent. Both mock-infected and coronavirus-infected cells had been pretreated with 10 µM inhibitor in medium for 48 h until infection. Following infection the basolateral medium was fully removed and fresh medium with the same inhibitor concentration (i.e., 10 µM) added, keeping the concentration constant at any given timepoint. (D) Representative immunoblot analysis of HCoV-229E N protein and loading control β-actin. (E) Illustration of Huh-7.5 infected with a variant of HCoV-229E expressing Renilla luciferase. Figure was created with biorender.com. (F) HCoV-229E infection of Huh-7.5 cells for 48 h: Renilla luminescence was quantified as a measure of viral replication. The results are shown in log scale (log₁₀ reduction). (G) Cell viability of Huh-7.5 cells after 48 h of inhibitor treatment was measured using the Celltiter-Glo assay and is shown in percent. (H) Illustration of transfection of HEK293 cells with a pBAC-SARS-Rep-Rluc plasmid expressing Renilla luciferase. Figure was created with biorender.com. (I) pBAC-SARS-Rep-Rluc transfection into HEK293 cells for 48 h: Renilla luminescence was quantified as a measure of viral replication. The results are shown in log scale (log₁₀ reduction). (J) Cell viability of HEK293 cells after 48 h of inhibitor treatment measured with the Celltiter-Glo assay. All results are shown as mean ± SEM.