Mind the Age Gap: Expanding the Age Window for mRNA Vaccine Testing in Mice

This data set supports work we look at the effect of animal age on the responses in expression potency and vaccine efficacy for LNP.

Figure 1. Overview of Publication Trends, Study Selection, and Mouse Age Distribution in mRNA Vaccine Research. (A) Number of publications per year identified in PubMed using the search terms "mice, mRNA, vaccines." The figure shows the trend in publications from 1987 to 31st Jan 2025 (access date: 31st January 2025). (B) A Sankey diagram illustrating the selection and categorisation of the most recent 100 publications from this PubMed search (generated by https://sankeymatic.com/build/). (C) Stacked column chart visualising the percentage distribution of mouse age groups identified in the 73 relevant publications.

Figure 2. Bioluminescent Imaging of Firefly Luciferase mRNA Expression in Mice of Different Ages. Mice were intramuscularly injected in both hind legs with mRNA (Fluc)-LNPs, and fluorescence intensity was measured in mice aged 4, 8 and 16 weeks old. The injected mRNA dose was 5 µg mRNA encapsulated in LNPs. Total flux from the hind leg region at 0.25, 6- and 24-hours post-injection with SM102 LNPs (A) or ALC-0315 LNPs (B). Corresponding total flux from the liver region (C, D). Bars represent mean ± SEM from n = 3 mice per group. (E, F) Representative in vivo images illustrating luciferase expression at the same time points for SM102 LNPs (E) and ALC-0315 LNPs (F).

Figure 3. Serum Antibody Responses in Mice Immunized with OVA-encoding mRNA LNPs. (A–C) Antibody titres on day 27 (post-prime), showing total IgG (A), IgG1 (B), and IgG2a (C) for SM102 LNPs (blue bars) and ALC-0315 LNPs (green bars) across 4-, 8-, and 16-week-old groups. (D–F) Corresponding titres on day 42 (two weeks post-booster). Bars represent mean reciprocal endpoint titres ± SEM (n = 5) (*P<0.05).