Figure 7.

Vaccination with AP205-RBD accelerated the viral clearance in the infected animals

(A–C) Swab samples were taken from the nasal cavity, throat, and rectum at the indicated time points after SARS-CoV-2 challenge and examined for viral loads.

(D) Tracheal brush samples taken at day 3 after viral challenge were examined for viral loads.

(E) Lung tissue samples taken from the euthanized animals at day 7 after viral challenge were examined for viral loads. Mann-Whitney test was used for statistical analysis in (D) and (E) (∗∗∗p < 0.001). (A–E) Symbols indicate data collected from individual animals, and bars indicate the geometric mean of each group.

(F–H) Histology examination of lung tissues. (F) Representative images of H&E staining at low magnification. Arrowheads point to lesion regions, which were surrounded with dashed lines. (G) Representative images at higher magnifications. Images were chosen from different individuals in both groups. The right panels are enlarged regions from the left panels. The arrowhead in (a, right panel) points to detached cells in the airspace. The severely infiltrated area, which is quantified as the consolidated area in (H), is illustrated in (c). (H) Summary of the proportion of the consolidated area in each tissue section. One section was taken from every lung lobe, with seven sections taken in total for each animal. Symbols indicate data of individual sections. Mean and standard deviation for each animal are shown. Nested ANOVA was used to compare the PBS- and AP205-RBD-immunized groups (∗∗p < 0.01).

ns, non-significant. See also Figure S6.