Bulk RNA sequencing reveals the comprehensive genetic characteristics of NK cells derived from human cord blood

Introduction: Cells of the innate immunity play an important role in tumor immunotherapy. Natural Killer cells (NKCs) are also categorized into those cells and be able to control tumor growth and metastatic spread. Glioblastoma (GBM) is the most common and aggressive primary brain tumor in adults. NKC-based immunotherapy is one of the promising treatment strategies against GBM. We previously reported the feeder-free expansion system, which yielded large scale highly purified and cytotoxic NKCs derived from human cord blood (CB). This study aimed to perform a comprehensive study of genomic analyses on NKCs generated from human CB.Methods: Frozen CB mononuclear cells (CBMCs) without T cells were cultured with recombinant human interleukin (rhIL)-18 and rhIL-2 in anti-NKp46 and anti-CD16 antibodies immobilization settings. After 7 days of expansion, the total RNA of NKCs derived from human CB or peripheral blood mononuclear cells (PBMC) was extracted and we performed genomic analyses to compare the similarities and differences with each NKC. We also examined the activity of each NKC against the GBM cell line.Results: According to the analysis of differential expression genes, some NK activating and inhibitory receptor were significantly downregulated in CBNKCs compared to PBNKCs. We also demonstrated upregulated genes related with Anti-apoptosis and Proliferation. In enrichment analysis, gene sets related to immune response and cytokine were detected enriched terms. We also performed Gene Set Enrichment Analysis (GSEA) and demonstrated that immune response pathway was upregulated in CBNKCs. Real time cell growth assays revealed that CBNKCs represented enhanced NK cell-mediated growth inhibition of GBM cells compared to PBNKCs.Conclusion: The present study demonstrated the characteristics of NKCs derived from human CM. Furthermore, the cell-based therapy using NKCs derived from human CB is promising to treat GBM.