Preliminary Exploration Of The Role Of Early Tumor Infiltration Of γδ T Cells Based On Single-cell Transcriptome Sequencing

Objective: To explore the heterogeneity of γδ T cells in the tumor microenvironment through preliminary excavation of single-cell transcriptome sequencing.Methods: B16 melanomas were implanted subcutaneously in 8-week-old C57BL/6mice,and single-cell suspensions were prepared for the early,middle and late stages of tumor formation,and the pure γδ was sorted by a sorting flow cytometer T cells,using single-cell transcriptome sequencing technology to analyze them,in-depth exploration of the heterogeneity of tumor-infiltrating γδ T cells compared to γδ T cells in peripheral tissues.Results: The single-cell transcriptome sequencing analysis of γδ T cells on the γδ T cells 9 days after tumor-bearing mice,which is the early stage of tumor occurrence,found that the infiltrating γδ T cells in the tumor were heterogeneous compared with those in the periphery.And through separate excavation of cluster1 and cluster5 subgroups,it was found that their high expression of killer molecules and cytotoxic substances were found.At the same time,through this sequencing,the chemokine receptors required for γδ T cells to migrate into the tumor were found,and the peripheral The γδ T cell subpopulations that are absent in the tissue but exist in the tumor tissue.By enriching the signaling pathways related to γδ T cells,it is found that γδ T cells in tumors up-regulate the JAK-STAT pathway and cytotoxic killing-related pathways,while down-regulating the MAPK signaling pathway.Further analysis of the transcription factors that regulate the function of γδ T cells revealed that the transcription factor Tox negatively regulates the ability of γδ T cells to produce IFN-γ,and the Bhlhe40 transcription factor promotes the production of IFN-γ by γδ T cells.At the same time,the m TORC1 signal can negatively regulate the expression of Tox.Conclusion: Through single-cell transcriptome sequencing,the heterogeneity of γδ T cells in tumors was analyzed from gene transcription level,signal pathway level,and transcription factor level,and it was found that the heterogeneity of γδ T cells in tumors was found regardless of cell type distribution,chemotaxis ability,and signal pathway enrichment.As well as the function of transcription factors,they are quite different from normal tissue γδ T cells.