Figure 5.

A strategy based on TS-associated mutations and adjusted with tailor-made S proteins to target different variants

(A) The construct of recombinant viruses which contained the Omicron spike with all the substitutions or deletions involved in temperature sensitivity.

(B) Temperature sensitivity of rTS-all-Omicron in vitro. VeroE6-TMPRSS II cells were infected with the recombinant strains and the Omicron variant and incubated under the indicated temperature conditions. CPE was observed three dpi by formalin fixation and crystal violet staining.

(C) Evaluation of the immunogenicity of the rTS-all-Omicron strain in vivo (n = 5).

(D)Neutralization titer of the sera from the hamsters infected with each strain. The individual neutralization titers are indicated with the corresponding symbols. Bars represent median values and error bars mean 95% CIs. For statistical analysis, the Kruskal-Wallis test was performed (n.s.: not significant). The LOD is indicated in the x axis.