Figure 2.

Immunogenicity and lyophilization of LNP-CoV mRNA containing lead L202

(A) The representative particle size of LNP-CoV mRNA containing L202, as determined by dynamic light scattering. (B) Cryo-EM image of LNP-CoV mRNA containing L202. (C) The dose-dependent activity of LNP-CoV. BALB/c mice (n = 6/group) received a single intramuscular injection of PBS, LNP-encapsulated luciferase mRNA in LNP (LNP-Luc mRNA), CoV mRNA alone, or LNP-encapsulated CoV mRNA ranging between 0.1 and 10 μg. (D) The representative appearance of lyophilized LNP-CoV mRNA and its reconstitution with water. (E) Immunization activity of wet or lyophilized formulations of LNP-CoV mRNA that were stored at 5°C, 25°C, or 40°C for 1 month. Mice (n = 6/group) received a single intramuscular injection of each LNP-CoV mRNA at 3 μg of mRNA dose. Plasma samples were collected 14 days after administering a single dose and were assessed for SARS-CoV-2 S1-specific IgG by ELISA (C and E). Data are presented as a GMT ± geometric SD. Groups were compared by a Kruskal-Wallis test with Dunn’s multiple comparison test (C). ∗p < 0.05, ∗∗p < 0.01, ∗∗∗p < 0.001; ns, not significant.