Figure 2.

Expression and Immunogenicity from LNPs Containing Novel Ionizable Lipids in Mice

(A) Thirty novel lipid LNPs, A through E′ were compared to a D (MC3) LNP control for expression and immunogenicity. Lipids are arranged left to right in order of pKa from low (A) to high (DOTAP). Expression measured by luminescence in flux (photons per second) 6 h after administration of modified mRNA encoding luciferase delivered at 0.5 mg/kg IV in CD-1 mice, 0.01 mg/kg IM or 0.001 mg/kg IM in BALB/c mice (n = 5 per group). Immunogenicity measured by H10-specific IgG titers measured 2 weeks after two doses administered 3 weeks apart delivered IM at 0.001 mg/kg IM in BALB/c mice (n = 5 per group). Data are represented as log₂ fold change compared to MC3. Squares containing an X indicate >4-fold change (log₂) lower than for MC3. (B) Log₂ fold increase in expression was compared to the log₂ fold change in immunogenicity at the low dose level administered IM (0.001 mg/kg). The five lead novel lipids and MC3 LNPs are labeled accordingly: MC3 (gray triangles), lipid H (green circles), lipid M (orange squares), lipid P (purple diamonds), lipid Q (tan inverted triangles), and lipid N (yellow hexagons). (C) Lipid pK_a versus fold increase in immunogenicity at 0.001 mg/kg IM for lipids A through E′. (D) Circulating IgG antibody (micrograms per milliliter of serum) 6 h after administration of 0.2 mg/kg modified mRNAs encoding the heavy chain and light chain of an influenza monoclonal antibody formulated at a 2:1 mass ratio in LNPs containing MC3 or novel lipids (n = 5 per group). *p < 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001, ordinary one-way ANOVA with Dunnett’s multiple comparisons test of each novel lipid versus MC3.