Fig. 5: Prophylactic intervention with antigen-loaded, mannosylated PSs ameliorates T cell-driven features of allergic airway inflammation.

a, A schematic depicting a prophylactic treatment schedule for allergic airway inflammation. C57BL/6 mice (n = 4 for T33M10-empty and T33M0-OVA, n = 5 for T33M10-OVA, and n = 2 for naive control) were prophylactically treated through i.v. injections of empty mannosylated (T33M10) PSs or OVA-loaded mannosylated (T33M10) or non-mannosylated (T33M0) PSs before induction of allergic airway inflammation. All encapsulated formulations consist of 100 µg polymer with 10 µg OVA and are benchmarked to the naive control. Mice were sensitized (sens.) through i.p. injections of OVA (or saline) adsorbed to alum (1:1, with 50 µg OVA), before i.tr. instillations with 25 µg OVA (chall.). b, Representative flow cytometry plots depicting airway eosinophils (highlighted in the box) isolated from BALF. c, Airway eosinophil and CD4⁺ T cell quantification as determined by flow cytometry. d, Lung eosinophil and CD4 ⁺ T cell quantification as determined by flow cytometry. e, Lung CD4⁺ effector T cells (T_eff) (FoxP3⁻CD44⁺CD62L⁻) and type-II lymphocytes (FoxP3⁻CD44⁺ST2⁺Gata3^hi) (Th2) as identified by flow cytometry. f, Systemic total IgE levels as determined by ELISA, quantified through AUC of concentration versus time (left, *P = 0.0430 for the comparison between T33M10-empty and T33M10-OVA. Comparison between T33M10-empty and T33M0-OVA, P = 0.6337) as well as final amount determined on day 20 (d20) of study (right). g, Ex vivo liver delivery comparing mannosylated to non-mannosylated PS delivery measured with IVIS. h, Total radiance quantification from IVIS (n = 2). Data are biological replicates plotted as box plots with max/min, median and quartiles (c–f), line graphs (f, left) or bar graphs (h) with mean ± s.e.m. and compared using ordinary one-way ANOVA with Sidak’s post-test for multiple comparisons. Panel a created with BioRender.com.