Figure 5.

Immunofluorescence of pharyngeal cells inoculated with SARS-CoV-2. Images were obtained by confocal microscopy (Leica SP8) at 400 × and 630 × and processed using ImageJ. The first photograph shows cell nuclei using DAPI staining. In the second and third photos, SARS-CoV-2 S (spike) protein are shown in red, demonstrating a perinuclear pattern. The same protocol described in Figure 3 was used to perform immunofluorescence. In this case, pharyngeal cells inoculated with SARS-CoV-2 were smeared and fixed with acetone.