Fig. 1: Improvement of COVID-19 pneumonia in rhesus macaques treated with SSK1.
From: Effective treatment of SARS-CoV-2-infected rhesus macaques by attenuating inflammation
a Scheme of the experimental design of late-stage SSK1 intervention. Black dot, measurement of clinical signs and blood samples at the indicated time points. Red dot, treatment. Brown triangle, sample collections following euthanasia. b Body weight changes of SARS-CoV-2-infected monkeys with vehicle, low-dosage (0.5 mg/kg) or high-dosage (2.0 mg/kg) SSK1 treatment between 22 and 32 dpi. c Representative necropsy images of lungs showing that SSK1 treatment reduced the lesions of lungs from SARS-CoV-2-infected monkeys. Left, vehicle treatment (RM1); middle, SSK1 treatment, 0.5 mg/kg (RM4); right, SSK1 treatment, 2.0 mg/kg (RM7). White circle, lung lesions. d H&E staining images showing that SSK1 treatment improved the pneumonia of monkeys that were infected with SARS-CoV-2. Top, from left to right, representative H&E images of lungs of monkeys treated with vehicle (RM3), 0.5 mg/kg (RM6) or 2.0 mg/kg (RM9) SSK1; bottom, high magnification images of the boxed area in the top line. Arrow, hemorrhage. Asterisk, edema. Scale bars, top: 200 μm; bottom: 50 μm. e Immunohistochemistry (IHC) analysis for CD68 in lung tissues collected from SARS-CoV-2-infected monkeys treated with vehicle, 0.5 mg/kg or 2.0 mg/kg SSK1. Top, low-magnification images; bottom, high-magnification images of the boxed area in the top line. Scale bars, top: 100 μm; bottom: 25 μm. f Quantification of the IHC staining of CD68-positive cells in lung tissues after treatment. Analyzed in 20 random fields (0.75 mm2 per field) per animal, 3 animals per group. Each data point represents an independent field of view in the IHC slides. Data were analyzed with one-way ANOVA, all error bars represent SEM, **P < 0.01, ****P < 0.0001. g Concentration change of inflammatory cytokines in serum samples from old monkeys before (21 dpi) and after (28 dpi) SSK1 treatment. h Concentration measurement for IL-18 in serum samples from SARS-CoV-2-infected monkeys before and after SSK1 treatment (2.0 mg/kg). Arrow, starting point of administration.
