Supplementary Figure 11 Low-dose doxorubicin affects the expression of CD112 and CD155 in NB cells. (A) The apoptosis of SH-SY5Y and SK-N-BE2 cells treated with low-dose doxorubicin (0.1 μM) is detected by FACS (left) and AV+ proportion is labeled in the representative FACS histograms. (B-F) CD112 and CD155 expression in SH-SY5Y and SK-N-BE2 cells or primary NB tumor cells treated with low-dose doxorubicin (0.1 μM) are detected by FACS and Western blot. MFI is labeled in the representative FACS histograms. (G) and (H) The cytotoxicity assays are performed to detected γδT-cell cytotoxicity against SH-SY5Y and SK-N-BE2 cells pretreated with 0.1 μM doxorubicin. The results are expressed as the means ± SEMs from at least three independent experiments. Significant differences between groups are represented by * p < 0.05 and *** p < 0.001.
ARTICLE ABSTRACT
The dynamic interplay between tumor cells and γδT cells within the tumor microenvironment significantly influences disease progression and immunotherapy outcome. In this study, we delved into the modulation of γδT-cell activation by tumor cell ligands CD112 and CD155, which interact with the activating receptor DNAM-1 on γδT cells. Spatial and single-cell RNA sequencing, as well as spatial metabolomic analysis, from neuroblastoma revealed that the expression levels and localization of CD112 and CD155 varied across and within tumors, correlating with differentiation status, metabolic pathways, and ultimately disease prognosis and patient survival. Both in vivo tumor xenograft experiments and in vitro coculture experiments demonstrated that a high CD112/CD155 expression ratio in tumors enhanced γδT cell–mediated cytotoxicity, whereas a low ratio fostered tumor resistance. Mechanistically, CD112 sustained DNAM-1–mediated γδT-cell activation, whereas CD155 downregulated DNAM-1 expression via E3 ubiquitin ligase tripartite motif–containing 21–mediated ubiquitin proteasomal degradation. By interacting with tumor cells differentially expressing CD112 and CD155, intratumoral γδT cells exhibited varying degrees of activation and DNAM-1 expression, representing three major functional subsets. This study underscores the complexity of tumor–immune cross-talk, offering insights into how tumor heterogeneity shapes the immune landscape.Significance: Tumor cells in different intratumoral neighborhoods display divergent patterns of ligands that regulate γδT-cell activation, highlighting multilevel regulation of antitumor immunity resulting from the heterogeneity of intercellular interactions in the tumor microenvironment.