Fig. 1

Two new subsets of memory CD4⁺ T-cells express Th17 lineage markers. a Memory CD4⁺ T-cells (CD3⁺CD4⁺CD45RA⁻) isolated from the peripheral blood of HIV-uninfected individuals were analyzed for their differential expression of CCR6, CCR4, and CXCR3. CCR6⁺ subsets included: CCR4⁺CXCR3⁻ (Th17), CCR4⁻CXCR3⁻ (double positive, CCR6⁺DP), CCR4⁺CXCR3⁺ (double negative, CCR6⁺DN), and CCR4⁻CXCR3⁺ (Th1Th17). CCR6⁻ subsets included: CCR4⁺CXCR3⁻ (Th2), CCR4⁺CXCR3⁺ (CCR6⁻DP), CCR4⁻CXCR3⁻ (CCR6⁻DN) and CCR4⁻CXCR3⁺ (Th1). Shown is the frequency of CCR6⁺ and CCR6⁻ subsets (b; n = 30) and their expression of CD161 (c; n = 8). Each symbol represents a distinct subject. Paired t-Test p-values are indicated on the figures. Horizontal bars indicate median values. d Shown are median frequencies of central (CM, CCR7⁺CD27⁺), transitional (TM, CCR7⁻CD27⁺) and effector (EM, CCR7⁻CD27⁻) memory cells per CCR6⁺ subset (n = 10). e–g FACS-sorted memory subsets (S1 Figure) were stimulated via CD3/CD28 for 4 days. e The production of the lineage-specific cytokines IL-17A, IFN-γ, and IL-5 was quantified by ELISA. Shown are results (mean ± SEM) on matched Th17, Th1Th17, CCR6⁺DN, CCR6⁺DP, and CCR6- (n = 3–7). Paired t Test p-values are indicated on the figures. f Transcriptional profiling were generated using the HumanHT-12 v4 Expression BeadChip; (Illumina). The heat map depicts differential expression of well-established Th17 and Th1 transcripts (identified as being up/down regulated in Th17 versus CCR6⁻DN, p value <0.05, fold change cut-off 1.3) in matched CCR6⁻DN versusCCR6⁺DN, CCR6⁺DP and Th17 (n = 4–6; up-regulated genes in red; down-regulated genes in blue)