Fig. 6
Monovalent RBDXBB.1.5-HR vaccine confers efficient protective immunity against the EG.5.1 infection in vivo. a The schematic representation of immunization and virus challenge schedule. NIH mice injected with adjuvant or 10 μg of adjuvanted RBDXBB.1.5-HR vaccine were intranasally challenged with live EG.5.1 viruses (1×106 PFU/mouse, n = 6 mice per group). The fluctuations in body weight loss (b) and viral genomic RNA (gRNA) loads in throat swabs (c) were monitored daily. d The virus infected mice were all euthanized on day 5 post infection for tissue collection, the tissues of nasal turbinates, trachea and lung were collected to detect the loads of gRNA by RT-qPCR. e Histopathological changes and pathological score in the lung tissue from mice challenged with live EG.5.1 virus. Scale bars represent 100 μm in (e). Data are presented as mean with SEM in (b–e). P values in (b and e) were performed by Unpaired Student’s t-tests, in (c, d) were conducted by Two-way ANOVA followed by Sidak’s multiple comparisons test, ****P < 0.0001; ***P < 0.001; *P < 0.05
