Neuroblastoma formation requires unconventional CD4 T cells and myeloid amino acid metabolism

Summary By mirroring their function as tissue repair organizers in normal tissues, immune cells regulate tumor growth. To understand the different facets of immune-tumor collaboration through genetics, spatial transcriptomics, and immunological manipulation with non-invasive, longitudinal imaging, we generated a penetrant double oncogene-driven autochthonous model of neuroblastoma. Using spatial transcriptomic analysis, we co-localized CD4 + and myeloid populations within the tumor parenchyma, while CD8 + T cells and B cells were peripherally dispersed. Depletion of CD4 + T cells or CCR2 + macrophages, but not B cells, CD8 + , or NK cells, prevented tumor formation. Tumor CD4 + T cells displayed unconventional phenotypes, were clonotypically diverse, and antigen-independent. Within the myeloid fraction, tumor growth required myeloid cells expressing Arginase-1. Overall, our results suggest that arginine-metabolizing myeloid cells conspire with pathogenic CD4 + T cells to create permissive conditions for tumor formation, and therefore suggest that these pro-tumorigenic pathways can be disabled by targeting myeloid amino acid metabolism.