Fig. 6: Inhibition of SARS-CoV-2 infection in mouse models by bruceine A and gamabufotalin.
From: Fluorogenic reporter enables identification of compounds that inhibit SARS-CoV-2
a, Schematic of the experimental design. K18-hACE2 mice were infected with SARS-CoV-2 (1,000 PFU) intranasally with either inhibitor or vehicle control (solvent) at day 0. Inhibitors were then delivered intranasally once per day on days 1 and 2. At 3 d.p.i., lung and brain were harvested for analysis. b, Virus titre measurement by plaque assay for lung and brain. n = 6 mice per group. Bruceine A and gamabufotalin were administered at 3.25 mg kg–1 by intranasal inoculation. P values, two-sided nonpaired Welch’s t-test between vehicle and treated groups. c, Immunofluorescence images of lung tissues. Slides were stained with antibodies against N, S, acetylated tubulin (AcTub) and DAPI. Immunofluorescence of N, S, AcTub and DAPI denoted by pseudocolours green, red, grey and blue, respectively. Lower panels correspond to boxed areas of upper panels. Scale bars: 100 μm (upper), 200 μm (lower). d, Quantification of immunofluorescence. Immunofluorescence samples were acquired from two mice for each group. Data presented as as mean ± s.d. P values, two-sided nonpaired t-test between vehicle and treated groups. ****P < 0.0001. Exact P values: anti-N: bruceine A 7.8 × 10–7, gamabufotalin 5.4 × 10–7; anti-S: bruceine A 8.8 × 10–7, gamabufotalin 6.0 × 10–7.
