Figure 1.
Design and characterization of LNP-encapsulated RBD mRNA vaccines against SARS-CoV-2. (A) Schematic diagram of RBD-WT (top panel) and RBD-Omicron (bottom panel) mRNA framework. Note that 15 mutations are located within Omicron RBD. UTR, untranslated regions; SPIL-10, human interleukin-10 signal peptide. (B) In vitro transcribed mRNA was transfected into HEK293T cells and the expression of RBD proteins within the cells were analyzed by immunofluorescence staining analysis with mouse anti-RBD polyclonal antibody and anti-mouse Alexa Fluor® 488 secondary antibody. Ctrl, mRNA encoding luciferase. RBD-O, mRNA encoding RBD-Omicron. Overlay, merge of the blue (DAPI) and green (RBD) channels. Scale bars = 20 μm. (C) The culture supernatants of mRNA-transfected HEK293T cells were analyzed for RBD expression by western blotting with HRP-conjugated anti-His tag antibody and anti-RBD polyclonal antibody as detection antibodies. M, marker.