CD4− lymphocytes with a highly differentiated memory phenotype are expanded in non-allergic asthma. (a) CD4− lymphocytes were identified by flow cytometry (left and middle dot plots). Then CD127 and CD26 were used to identify five subsets within the CD4− lymphocyte compartment (right dot plot). (b) Percentage of CD4−CD26+ or CD4−CD126+ cells from healthy controls (HC; N = 32), rhinitis (R; N = 44), allergic asthma (AA; N = 100) and non-allergic asthma (NAA; N = 92). (c) Percentage (median ± IQR1-3) of CD26−CD127−, CD26intCD127+, and CD26highCD127+ cells amongst CD4− lymphocytes in HC, R, AA, and NAA. (d) Composition of CD4− lymphocyte subsets based on CD3 (T), CD8 (Tc), CD19 (B), and CD56 (NK, NKT) antigens (Data from 3 representative donors). (e) Phenotypic analysis of CD4− subsets based on CD45RA, CCR7, CD127, CD28, and CD27 markers (data from 3 representative donors). Statistically significant differences between groups are indicated (Kruskal-Wallis test: P < 0.05). In order to make the figure more understandable, sections (c,d and e) show only those CD4− subsets gated in (a) (right dot plot) where differences between groups were observed (CD26−CD127−, CD26intCD127+, and CD26highCD127+ cells).