Fig 2: Blocking of IL-13 signaling decreases phosphorylation of STAT6 and mucus production in Fra2 TG mice. (A) Schematic representation of intraperitoneal (i.p.) treatment with IL-13 blocking antibody (anti-IL-13) or isotype control (IgG), n = 5 – 8 animals per group. (B) Western blot analysis and quantification of phosphorylated (p) and total STAT6 levels in mouse lung homogenates, ***p < 0.001. (Uncropped scans of the original membranes can be found in Figure E3). (C) Representative images (from n = 3) of immunofluorescence staining of MUC5AC (green) and CLCA1 (red) in bronchi of WT and Fra2 TG mice treated with control IgG or anti-IL-13 neutralising antibodies.

Fig 3: Representative images with immunofluorescence and histological analysis of MUC5AC in the conjunctival epithelium on day 14. Control experiment showed no green fluorescence in the conjunctival epithelium in the control group (A) and the dry group (B). No positive stained cells were observed in the cornea (C), which served as a negative control. The expression of the MUC5AC protein was marked with green fluorescence (arrows) in the conjunctival epithelial cytoplasm of the normal rabbits (D). In the dry group, fewer cells with green fluorescence were noted in the conjunctival epithelium on day 14 (E, F; **P < 0.01, n = 3 [6 eyes] per group). Data are shown as mean ± SD (error bars). Magnification, × 200.

Fig 4: ACE2 protein and mRNA expression are not found in secretory goblet cells of the human airway.a Representative immunofluorescence double staining of ACE2 and mucin 5AC (MUC5AC) reveals absence of co-localization of ACE2 within secretory goblet cells in the human nasal turbinate, uncinate process, and bronchus. b Representative in situ hybridization using an ACE2 probe in combination with an anti-MUC5AC antibody. ACE2 mRNA expression (red dots) was not detected within goblet cells marked by MUC5AC in the nasal turbinate, uncinate process, and trachea. Nuclei were stained using DAPI. Scale bars: 20 µm (top) and 5 µm (bottom).

Fig 5: Resurrection and cellular characterisation of 2D enteroids after cryopreservation. Immunolocalisation of 2D enteroids grown from cryopreserved intestine cells on Matrigel-coated transwells, on day 4 of culture. Z stack of co-immunolocalisation of F-actin (apical brush border, red) with intestinal epithelial cells (green); A ZO1 (Tight Junctions), B Villin (enterocytes), C Lysozyme (Paneth cells), D Muc5AC (Goblet cells) and E Chromogranin A (enteroendocrine cells). F Magnification of Z-stack of Muc5AC showing DAPI stained nuclei in basal cells (white arrow heads). Scale bars: 15 µm. G Vimentin expression (green) in basal mesenchymal cells in the absence of epithelial cells. Scale bar: 50 µm. Nuclei are stained with DAPI. The data represents three independent experiments. H, I Cells were thawed and grown as 2D enteroids in transwells; CHIR99021 was added to Maintenance Media for H 24 h and I 72 h. Data is the median of 3–4 independent experiments and 95% CI.