Table 2.
Lesions and viral RNA (in situ hybridization) and nucleocapsid immunolabeling in the nasal passages of K18-hACE2 Tg mice (n = 3), hACE2 Tg mice (n = 3), and hamsters (n = 3 per time point) infected with SARS-CoV-2.
| K18-hACE2 Tg mice | hACE2 Tg mice | Syrian hamsters | |||
|---|---|---|---|---|---|
| 3 dpi | 5 dpi | 7 dpi | 14 dpi | ||
| Moderate | Mild | Severe | Mild | ||
| Epithelial lesion scores | Squamous | 0 | 0 | 0 | 0 |
| Respiratory | 1 | 0 | 3 | 0 | |
| Olfactory | 2 | 0 | 4 | 0 | |
| ISH (viral RNA) | Squamous | — | — | — | — |
| Respiratory | + | — | +/− | — | |
| Olfactory | ++ | +/− | + | — | |
| IHC (viral nucleocapsid) | Squamous | + | +/− | + | — |
| Respiratory | ++ | +/− | ++ | — | |
| Olfactory | ++ | +/− | ++ | — | |
Lesion severity was scored by the distribution or extent of lesions as follows: 0, no visible changes; 1, mild focal or multifocal changes; 2, moderate multifocal changes; 3, moderate diffuse changes; 4, severe diffuse changes. The intensity of positive IHC or ISH signals in nasal cavities was scored as follows: −, no detectable signal; +/−, weak or faint signal; + moderate, readily detectable signal; ++, strong, intense signal.
Abbreviations: hACE2, human angiotensin-converting enzyme 2; Tg, transgenic; SARS-CoV-2, severe acute respiratory syndrome coronavirus-2; IHC, immunohistochemistry; ISH, in situ hybridization.