Characterization of PB ILCs. (A) HSNE analysis of the ILC population in PB (n = 8). Total PB lymphocytes were stained with antibodies against Lin (CD1a, CD3, CD4, CD5, CD14, CD19, CD16, CD34, CD94, CD123, BDCA2, TCRαβ, TCRγδ, and FcER1α) and ILC-related molecules as indicated. The Lin⁻CD127⁺ population (ILCs) was further analyzed to identify clusters based on the expression of different cell-surface molecules. Two clusters are indicated as A and B, and cluster B is subdivided into three subclusters (B1, B2, and B3). (B) Heatmap of expression intensity of cell-surface molecules on different ILC clusters. (C) Zoom-in of cluster A by HSNE. The circle indicates a population that expresses KLRG1 but lacks CRTH2. (D) Gating strategy for flow cytometric analysis of PB ILC subsets (three upper plots) and histogram of CD7 and IL1R1 expression on ILC subsets (bottom). (E) KLRG1, CD56, and IL1R1 expression pattern on ILC subsets (three upper plots), and histogram of several ILC associated cell-surface molecules on KLRG1⁺ ILCs (Lin⁻CD127⁺CD117⁺CRTH2⁻NKp46⁻KLRG1⁺), ILC2s (Lin⁻CD127⁺CRTH2⁺), and NKp46⁺ ILCs (Lin⁻CD127⁺CD117⁺CRTH2⁻CD56⁻NKp46⁺; bottom). Filled histogram represents isotype control (CTRL). (F) Frequency of each subset indicated within the CD117⁺ CRTH2⁻ ILC population from PB (n = 9). (G) Gating strategy used for flow cytometric analysis of ILC subsets in NPs and tonsils. Data in D, E, and G are representative of at least three donors from at least three independent experiments.