Fig. 6: The glycocode of tumor cells dictates DC metabolism.

PanDCs (mixture of cDC2s, cDC1s and pDCs) purified from HD blood were co-cultured with primary tumor cells from melanoma patients for 20 h, and further stimulated or not with TLR-L (polyI:C or R848). Their metabolism was then studied by flow cytometry using the SCENITH method, and their production of cytokines was assessed by intracellular cytokine staining using flow cytometry. In parallel, the GLYcoPROFILE™ (lectin arrays from GLYcoDiag) have been determined on the melanoma tumor cell lines to depict their glycocode (see ref. ¹⁶). A Experimental design. Created in BioRender. Demars, E. (2025) https://BioRender.com/y60r598. B Tumor cells were classified according to their capacity to either inhibit (negative impact, red symbols) or boost (positive impact, blue symbols) DC cytokine production (as defined in ref. ¹⁶), and the metabolic parameters of cDC1s and pDCs in co-culture with these two groups of tumor cells were compared. Bars indicate median. P-values were calculated using a two-tailed Mann-Whitney test, or a non-parametric two-way ANOVA, followed by Sidak’s multiple comparison post-tests (n = 9 and 7 tumors with respectively negative and positive impact for cDC1s; n = 7 and 9 tumors with respectively negative and positive impact for pDCs). *P ≤ 0.05. Only significant statistics are displayed on graphs. C Correlations between the expression of specific glycans by primary tumor cell lines (revealed by lectin binding, e.g., HPA for GalNAc, MAA for NeuAc, PSA for Man/Glc motifs) and the metabolic parameters of DC subsets in co-culture with the corresponding tumor cell lines (22–23 donors) (Spearman correlation). Graphs correspond to the correlations obtained with cDC2s (upper graphs) or pDCs (bottom graphs) and their global metabolism (MFI of puromycin), or glucose (Glc) and/or mitochondrial (Mit) dependencies (Dep) after TLR stimulation (stim) or not (no stim). Source data are provided as a Source Data file.