Extended Data Fig. 9: Gel-forming mucins promote SARS-CoV-2 entry.
a. RT-qPCR analysis of target-gene expression for indicated GOF cell lines graphed as expression fold change over NTG for each gene. Statistical significance is measured by individual two-sided t-tests comparing GOF lines to NTG, n = 4 biological replicates. Dotted line indicates NTG expression level (normalized to 1). b. Western blot analysis of MUC5AC GOF Calu-3 cells. Bottom panel was imaged in a different channel or lanes were cropped out between the ladder and target lanes (upper left). One western blot was conducted in this experiment. c. Plaque assay on the indicated Calu-3 GOF cells infected with SARS-CoV-2 for 24 hours at an MOI of 0.1. Significance was determined by two-sided t-tests comparing individual GOF cell lines to NTG, n = 3 biological replicates. d. Pseudotype-entry assay measuring GFP + cells at 12 hpi with VSV-CoV-2-S (SARS-CoV-2 Spike-pseudotyped Vesicular stomatitis virus encoding GFP). Significance was determined by two-sided t-tests comparing individual GOF cell lines to NTG, n = 3 biological replicates. Dotted line indicates the NTG average. e. Incucyte trace tracking GFP+ (VSV-CoV-2-S infected) cells from the same experiment shown in (d). f. RT-qPCR analysis of SARS-CoV-2 N gene copies 24 hpi of four different SARS-CoV-2 variants in the indicated mucin GOF Calu-3 cells, graphed as normalized to NTG average (indicated by a dotted line). Significance was determined by individual two-sided t-tests comparing the GOF mucin line to NTG, n = 3 biological replicates. For all panels: error bars denote mean ± s.e.m., significance is indicated as: n.s.=not significant, *= P < 0.05, **= P < 0.01, ***=P < 0.001, ****= P < 0.0001.
