Fig. 4: High potency IL-17A promoting adjuvants restore vaccine protection in SA-exposed mice.

a SA-exposed WT mice were treated with either isotype IgG1 control or anti-IL-10 MAb before and on the day of AIsdB vaccination as in Fig.2b. Then, splenic CD4⁺ T cells were purified 14 dpv and incubated with naïve splenocytes plus IsdB (10 µg/ml). IL-17A and IFN-γ from culture supernatant were measured at 60 h (n = 5 per group). b, c Naïve or SA-exposed WT mice were vaccinated i.p. with Alum (n = 23 in b and 19 in (c), AIsdB (n = 22 in b and 20 in c), CAF01 (n = 30 in (b) and 25 in c) or CAF01IsdB (n = 32 in b and 26 in c), then challenged with SA 14 dpv. d, e Naïve or SA-exposed WT mice were vaccinated i.p. with Alum (n = 10 in (d) and 14 in (e), AIsdB (n = 10 in d and 14 in e), AlumTDB (ATDB) (n = 9 in d,e) or ATDBIsdB (n = 13 in d,e), then challenged with SA 14 dpv. f SA-exposed WT mice were vaccinated with either PBS or IsdB plus adjuvant. Splenocytes (pooled from three mouse) were purified 14 dpv and stimulated with IsdB (10 µg/ml) for 60 h, followed by analysis of supernatants for IL-17A. Data were from one to 4 independent experiments with each data point representing one mouse, except in (f). The data are presented as mean ± SD of biological replicates, except for (f), where data are presented as mean ± SD of three technical replicates of one independent experiment, repeated twice with similar results. The data in (a, f) were analyzed by one-way ANOVA with Tukey’s post-hoc test while the data in (b–e) were analyzed by Kruskal-Wallis non-parametric one-way ANOVA test. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001. ns, non-significant. dpv, days post-last vaccination. SA, Staphylococcus aureus. WT-wild-type. Source data are provided as Source Data File. Mouse image was created by BioRender (Created in BioRender. Hajam, I. (2024) https://BioRender.com/a18v205).