a, Mann-NC is a nano-PAMP that engages Dectin-2 and TLR-4 on DCs for TH17-skewed immune activation. TH17 cells supported by IL-23, IL-6 and IL-1β orchestrate the intra-tumoural recruitment of CD8+ T cells and NK cells via chemokines, including CXCL10 and CCL2, leading to potent anti-tumour efficacy. b, Mann-NC is composed of mannan with α-(1,6) mannoside backbone and α-(1,2) and α-(1,3) mannoside side chains. c, TEM images of a template siNP and hollow Mann-NCs. Scale bars, 100 nm. d,e, AFM images show Mann-NC in dried (top) and wet conditions (bottom) (d) and wall thickness of Mann-NC measured in dried condition (e).