Fig. 6: Co-localization of tumour antigen and LND-CDN nanoparticles in lymph node dendritic cells leads to effective antitumour T-cell priming.

a,b, Mice with MC38 tumours (n = 5 animals per group) were treated as in Fig. 4a. Depleting antibodies against CD8 (αCD8) (a) or NK1.1 (αNK1.1) (b), or their respective isotype control antibodies (Iso), were administered on days 6, 8, 11 and 15 after tumour inoculation. The graphs show the average tumour growth versus time (error bars, s.e.m.) and the common PBS control group is shown in both graphs for clarity. c–h, C57Bl/6 mice (n = 5 animals per group) were inoculated with 5 × 10⁵ MC38-ZsGreen tumour cells in the flank, and 7 d later were left untreated or treated with Cy5-labelled LND-CDN or liposome-CDN (5 nmol CDN). Between 1 to 3 d later, TDLNs were isolated for flow cytometry analysis. Shown are representative flow cytometry plots of tumour antigen and nanoparticle uptake in DCs at day 2 (c), mean ± s.e.m. percentages of tumour antigen ZsGreen⁺NP⁺ DCs (d), area-under-the-curve (AUC) of Ag⁺NP⁺ DCs over time (e), analysis of mean ± s.e.m. percentages of LND-CDN⁺ DCs that are Ag⁺ or Ag^- (f), representative flow cytometry plots of tumour antigen uptake and CD86 upregulation in DCs at day 3 (g), and mean ± s.e.m. percentages of tumour antigen ZsGreen⁺CD86⁺ DCs (h). i, MC38-tumour-bearing mice (n = 10 animals per group) were treated with LND-CDN or liposome-CDN as in a, and tumour-specific T cells were assayed by IFN-γ ELISPOT 14 d following treatment. j, MC38-tumour-bearing mice (n = 5 animals per group) were treated on day 7 by intratumoral injection of 5 nmol LND-CDN or liposome-CDN. Shown are mean ± s.e.m. tumour area and survival. Statistical analysis of tumour growth in a, b and j was performed using one-way ANOVA with Tukey’s multiple-comparisons test. Statistical comparisons among cell percentages and AUCs in d–f and h, and tumour growth in j (day 18) were tested using an ordinary one-way ANOVA with Tukey’s multiple-comparisons test. Statistical comparisons among groups in i were tested using Brown–Forsythe and Welch’s ANOVA tests with Dunnett’s T3 multiple-comparisons test. Statistical comparisons between survival curves in j were performed using a log-rank (Mantel–Cox) test.