Fig. 1: Induction of Type I IFN and intermediate monocytes after mRNA vaccination.

a Outline of study design with respect to group and vaccine assignment, group composition, vaccine dose/route of administration, number of vaccine doses, time interval between each dose and sampling timeline. Red, green and blue will be the color coding for data referring to groups 1, 2 and 3 respectively throughout the manuscript. Full black circles and empty white circles across the study timeline indicate blood draws and bone marrow aspirates respectively. b Dot plot of the detectable plasma cytokine and chemokine levels showing significant differences between the groups measured by a 30-plex assay. The values shown refer to the levels measured at day 0 (prior to prime immunization), day 1 (peak response) and day 14 (return to steady-state levels). Direct comparisons are shown for each cytokine between combined groups 1 and 2 (as at this time of the study, they both received one dose of the mRNA vaccine and are therefore equivalent) and group 3. n = 18 biologically independent animals. Statistical differences were assessed at day 1 comparing groups using Mann–Whitney U test. Cytokine concentrations undetectable or below lower limit of quantitation (LLOQ) are shown as LLOQ value. Dotted lines indicate LLOQ. Representative flow cytometry plots (c) and longitudinal data (d) showing the differentiation and temporary fluctuation of intermediate monocytes. Data are shown for day 0 (prior to prime immunization), day 1 (peak innate response) and day 14 (return to steady-state levels). Complete gating strategy for the identification of monocytes is shown in Supplementary fig. 11b. Statistical differences in (d) were assessed at day 1 using Mann–Whitney U test. n = 18 biologically independent animals. All statistical tests comparing the study groups were two-tailed tests. All error bars indicate mean ± SD.