Fig. 1

MUC15 was upregulated after H3N2 infection in hNECs a: Fold changes of MUC mRNA expression in hNECs infected by H3N2 at 48 h post infection (hpi) with uninfected subjects (Uni) as baseline, detected by RNA sequencing (black column, n = 3) and mRNA array (white column, n = 5). b: Quantitative real-time RT-PCR analysis of MUC genes in hNECs infected with H3N2 with uninfected control subjects as baseline (n = 13), using PGK1 as the internal control. Relative mRNA expression levels were calculated using 2^ ^(−ΔΔCt) method; the fold change was calculated compared against uninfected control subjects. c: Western blot analysis of MUC15 protein expression on hNECs infected with H3N2. Cells were harvested at various times as indicated. d: The western blot band intensities were measured using Image J, and graph is presented as the ratio of MUC15-to-GAPDH and then normalized to each uninfected control (n = 5) (left y axis and bars). Plaque assay show viral replication in hNECs infected by H3N2 (n = 8) (right y axis and spots). e: IF co-staining of MUC15 (red) and HA (green) on fully differentiated hNECs with or without H3N2 infection (Cell nuclei are stained in blue with DAPI, 49–6-Diamidino-2-phenylindole dihydrochloride). */§, **/^##, ***/^###, **** denotes P value of less than 0.05, 0.01, 0.001, < 0.0001 compared with uninfected control, respectively. Median values with 25th and 75th percentiles are indicated by error bar. Uni: uninfected control