Fig. 1: MERS-CoV S-2P mRNA protects mice from lethal challenge.
From: SARS-CoV-2 mRNA vaccine design enabled by prototype pathogen preparedness
a–d, 288/330+/+ mice were immunized at weeks 0 and 3 with 0.01 (green), 0.1 (blue) or 1 μg (red) MERS-CoV S(2P) mRNA. Control mice were administered phosphate-buffered saline (PBS) (grey). a, Two weeks post-boost, sera were collected from three mice per group and assessed for neutralizing antibodies against MERS m35c4 pseudovirus. b–d, Four weeks post-boost, 12 mice per group were challenged with a lethal dose of mouse-adapted MERS-CoV (m35c4). b, Following challenge, mice were monitored for weight loss. c, d, Two days post-challenge, at peak viral load, lung viral titres (c) and haemorrhage (scored as: 0, no haemorrhage, 4, severe haemorrhage in all lobes) (d) were assessed from five mice per group. In c, d, all dose levels were compared by Kruskal–Wallis analysis of variance (ANOVA) with Dunn’s multiple comparisons test. In b, for weight loss, all comparisons are with PBS control mice at the same time point by two-sided Mann–Whitney U-test. **P < 0.01, ****P < 0.0001. Data are GMT ± geometric s.d. (a, c) or mean ± s.d. (b, d). In c, the dotted line represents assay limit of detection.
