Single-cell RNA-seq of UTCaß population in sarcoma mice models

Neutrophils represent a fundamental mechanism of antimicrobial resistance and inflammation 1. Moreover, neutrophils have emerged as important players in the activation, orchestration and regulation of adaptive immune responses2,3. Neutrophils are a component of the tumor microenvironment (TME) and have been prevalently shown to promote progression 4-6. On the other hand, unleashed neutrophilic effectors have also been reported to mediate anti-cancer resistance7-11. Antibody-mediated depletion used to investigate the role of neutrophils in tumor progression suffers from limitations, including duration, specificity and perturbation of the system12. We therefore used a genetic approach to investigate the role of neutrophils in primary 3-methylcholanthrene (3-MCA)-induced sarcomagenesis. Neutrophils were found to play an essential role in resistance against primary carcinogenesis by driving an interferon-? dependent type 1 immune response. Neutrophil-dependent macrophage production of IL-12p70 led to type 1 polarization of CD4- CD8- unconventional aß T cells (UTCaß) in the TME. Single cell RNAseq analysis and in vivo evidence from two preclinical sarcoma models highlight the antitumor potential of a UTCaß subset. In the TCGA cohort of human undifferentiated pleomorphic sarcomas (UPS), unlike other sarcomas, granulocyte-colony stimulating factor receptor (CSF3R) expression and a neutrophil signature were associated with better outcome and with a type 1 immune response. The positive association between high neutrophil infiltration and improved clinical outcome was confirmed in an independent UPS cohort by immunohistochemistry. Thus, neutrophils, by driving a type 1 immune response and polarization of UTCaß, mediate resistance against murine and human sarcomas. Overall design: two experimental conditions, two biological replicates for each condition

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Ponzetta A, Carriero R, Carnevale S, Barbagallo M, Molgora M, Perucchini C, Magrini E, Gianni F, Kunderfranco P, Polentarutti N, Pasqualini F, Di Marco S, Supino D, Peano C, Cananzi F, Colombo P, Pilotti S, Alomar SY, Bonavita E, Galdiero MR, Garlanda C, Mantovani A, Jaillon S