Integrated Analysis of Single-Cell and Bulk RNA Sequencing Data Reveals Memory-like NK Cell Subset Associated with Mycobacterium tuberculosis Latency

• Published in: Cells (Basel, Switzerland) Vol. 13; no. 4; p. 293
• Main Authors: Shekarkar Azgomi, Mojtaba, Badami, Giusto Davide, Lo Pizzo, Marianna, Tamburini, Bartolo, Dieli, Costanza, La Manna, Marco Pio, Dieli, Francesco, Caccamo, Nadia
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 06.02.2024
• Subjects: Cells; Cytokines; Decomposition; Drb1 protein; Flow cytometry; Gene expression; Humans; Immune response; Immunity, Innate; Immunization; Immunosurveillance; Infections; Infectious diseases; Killer Cells, Natural; Latency; latent Mycobacterium tuberculosis infection; Ligands; Lung diseases; Lymphocytes; Lymphoid cells; Mycobacterium tuberculosis; Natural killer cells; NK Cell Lectin-Like Receptor Subfamily C; NK cells; NKG2 antigen; NKG2C; Peripheral blood; Ribonucleic acid; RNA; Sequence Analysis, RNA; single-cell RNA sequence; Tuberculosis; Tumor cells; NK cells; latent Mycobacterium tuberculosis infection; Mycobacterium tuberculosis; single-cell RNA sequence; NKG2C; tuberculosis
• ISSN: 2073-4409; 2073-4409
• DOI: 10.3390/cells13040293

Natural killer (NK) cells are innate-like lymphocytes that belong to the family of type-1 innate lymphoid cells and rapidly respond to virus-infected and tumor cells. In this study, we have combined scRNA-seq data and bulk RNA-seq data to define the phenotypic and molecular characteristics of peripheral blood NK cells. While the role of NK cells in immune surveillance against virus infections and tumors has been well established, their contribution to protective responses to other intracellular microorganisms, such as Mycobacterium tuberculosis (Mtb), is still poorly understood. In this study, we have combined scRNA-seq data and bulk RNA-seq data to illuminate the molecular characteristics of circulating NK cells in patients with active tuberculosis (TB) disease and subjects with latent Mtb infection (LTBI) and compared these characteristics with those of healthy donors (HDs) and patients with non-TB other pulmonary infectious diseases (ODs). We show here that the NK cell cluster was significantly increased in LTBI subjects, as compared to patients with active TB or other non-TB pulmonary diseases and HD, and this was mostly attributable to the expansion of an NK cell population expressing KLRC2, CD52, CCL5 and HLA-DRB1, which most likely corresponds to memory-like NK2.1 cells. These data were validated by flow cytometry analysis in a small cohort of samples, showing that LTBI subjects have a significant expansion of NK cells characterized by the prevalence of memory-like CD52+ NKG2C+ NK cells. Altogether, our results provide some new information on the role of NK cells in protective immune responses to Mtb.