Figure 2.

The phenotype and attenuation of the TS strains are attributed to the substitutions nsp14 248V plus 416S, nsp3 445F, and nsp16 67I

(A) The construct of recombinant viruses bearing the substitutions or the deletion found in the TS strains.

(B) The growth kinetics of recombinant viruses at different temperatures. Vero cells were infected with each strain at MOI = 0.01. The viral titer of the supernatant was calculated by TCID₅₀ using Vero cells. Symbols represent the average of three independent experiments, and error bars mean SDs. For samples below the LOD, the assay’s LOD was used to calculate the mean. The LOD is 2.65 log₁₀ TCID50/mL, indicated in the x axis. To compare titers on the same day between the B-1 and the other strains, two-way ANOVA was performed.

(C) Evaluation of the pathogenicity of recombinant viruses in vivo (n = 5).

(D) Weight change in the Syrian hamsters infected with the recombinant viruses. The average weight changes are represented by symbols, and SDs are represented by error bars. For statistical analysis, two-way ANOVA was performed.