Fig. 2

Transfected HEK293T cells with respective mRNAs were observed using flow cytometry. A Schematic diagram illustrates the transfection process. B, C Flow cytometry data showed the successful transfection of mRNAs. D Schematic diagram depicts the animal immunization process. E ELISA was used to evaluate the binding activity of immunized serum against proteins from each variant. All experiments were performed in triplicate; standard deviations are shown as error bars. Graphical data are shown as mean ± SEM. The WT treatment was used as a control group in a two-tailed Student’s t test; *p < 0.05, **p < 0.01