a Representative dose-response curves of IFN-β production in human PMBC supernatant after treating with two different CDN-loaded EVs, exoCDN1 and exoCDN2, compared with free CDNs (n = 2 biological replicates per donor). Biological replicates (three healthy donors) are presented in Supplementary Fig. 2b. b EC50 value of IFN-β production in human PBMC after treating with free CDN1 and exoCDN1 (n = 12 healthy donors). c Representative dose-response curves (n = 3 healthy donors) of IFN-β production in PBMC after treating with free CDN1, free CDN1 with EVs, and exoCDN1 (n = 2 biological replicates per donor). ****P < 0.0001 by unpaired t-test. d–f C57BL/6 mice were implanted subcutaneously with 1 × 106 B16F10 cell on right flank of mice. Additional implantation of tumors is specified in each legend. When tumor volumes reached 50–100 mm3, testing agents were injected intratumorally three times with 3 days interval. Red arrows in the graph indicate IT injection days. Tumor growth were measured over time (n = 5 animals per group). CDN1 MR SS-2 CDA, CDN2 cAIM(PS)2 Difluor (Rp/Sp), RLU relative luminescent unit. Data are presented as means ± s.e.m from replicate samples as indicated. ****P < 0.0001 by two-way ANOVA with Tukey’s multiple comparison test for tumor growth studies.