T/NK cell population is divided into two clusters based on their functions
T cells are broadly classified into two subsets namely CD4+ T cells and CD8+ T cells based on their expression of markers and functions. In the present study, CD4+ and CD8+ cells were categorized as cluster 2 and cluster 1 respectively (Figure 1a) and were further subdivided into 9 subgroups (T0–8) (Figure 3a) . T0 subclusters contained genes expressing CD2, CD3D, CD3G and low CD8A along with significant expression of NKG7, GZMH and GZMB, a classic NK cell feature, and were therefore classified as cytotoxic NKT cells(Figure 3b, c, d) (25). T1 subcluster consisted of genes expressing IL7R, MAL, and CCR7, an indicator of CD4+ T cell maturation (Figure 3b, d) (24, 26, 27). T2 subcluster consisted of GZMB, GZMA, high GNLY, NKG7, and FCGR3A (CD16) with low CD3D and CD3G expression and were classified as CD56dim CD16+ NK cells(Figure 3b, c) (25, 28, 29). T3 consisted of IL7R, MAL, CCR7 genes with significantly higher CD69 expression, indicating more active CD4+ T cell (Figure 3d) (24, 26, 27, 30). T4 consisted of genes featuring NK cell markers (NKG7 and GNLY) and genes with role in antigen recognition and presentation (LYZ, S100A8, and S100A9) and were identified as NK cell-derived antigen-presenting cells (APCs) (Figure 3b, d) (28, 29). T5 was considered as an unknown group with fewer genes. T6 were identified as NK cells (low GNLY, NKG7; high NKTR) with high XIST1 and SYNE2 indicating autophagic NK cells with low ribosomal expression (Figure 3b, d) (28, 29). Similar to the previous NK cells, T7 subgroup (GNLY, NKG7, high CD7, XCL1, and XCL2) was classified as cytokine induced memory like NK cells (CIML)(Figure 3d) (28, 29) and T8 (high GNLY and NKG7, IFIT2, IFIT3, IFNG, and PMAIP1) was identified as cytokine secreting CD56neg NK cells (Figure 3b) (28, 29).