Double IHC staining in medial turbinate of pigs and medial/caudal turbinate of llamas at different time‐points post‐inoculation. (a) Medial turbinate; pig, day 2 p.i. DPP4 antigen (pink staining) is located mainly in the cytoplasm of epithelial cells, endothelium (thick arrow), macrophage‐like cells (curved arrows) and glandular cells in submucosa (asterisk). Several epithelial cells with cytoplasmic presence of MERS‐CoV antigen (brown) also contain DPP4 (arrows). Also, one MERS‐CoV positive cell does not display DPP4 staining (arrowhead). (b) Medial turbinate; pig, day 4 p.i. Both DPP4/MERS‐CoV double stained cell (arrow) and cells harbouring only MERS‐CoV antigen (arrowheads) are displayed. (c, d) Medial and caudal turbinates, respectively; llama, day 4 p.i. DPP4 expression (pink staining) is mostly restricted on lining cilia, submucosal glands (arrows) and capillaries (arrowheads). Co‐localization of DPP4 (pink) and MERS‐CoV (brown) antigens is observed in all infected cells. Original magnification: ×400 for all tissues [Colour figure can be viewed at http://wileyonlinelibrary.com]