The frequency of PB gut homing CD4+ and CD8+ T-cells is altered in HIV infection.

<p>Frequencies (expressed as percentages) of peripheral blood (PB) memory gut homing (CD45RO+ CCR9+ β7+) CD4+ (A) and CD8+ (B) T-cells was determined by flow cytometry on PBMCs of HIV-infected individuals (HIV+), antiretroviral (ART) naïve (n = 18), ART experienced individuals on short-term (n = 15) and long-term treatment (n = 32), HIV controllers (n = 6) and HIV seronegative individuals (SN, n = 5). Scatter plots were used to represent the data. Horizontal lines indicate median values. Each symbol represents one individual. The red symbols represent the females in each group. Groups were compared using Kruskal-Wallis test correcting for multiple comparisons using the Dunnett´s post-test. Only significant corrected p values are shown ***p<0.0005, **p<0.005, *p<0.05. Gender was color-coded as follows: red dots, women and black dots, men.</p

Gating strategy.

<p>The gating strategy used for all the samples was to first define singlet and morphology by using forward versus side scatter, followed by the exclusion of dead cells (aqua dye negative events) and the exclusion of CD14, CD19, CD56, CD11c and CD123 positive cells (dump gate). Live cells were gated on CD3+ and CD45RO+ cells. Next, CCR9+ and/or β7+ cells were gated and defined as gut homing T-cells. Then CD4+ and CD8+ T cells were gated and finally the expression of CD161 on the gut homing CD4+ (top) and CD8+ (bottom) T-cells was gated. T cell activation was determined by the simultaneous expression of CD38 and HLADR on gut homing CD4+ and CD8+ T cells.</p

ART-naive and short-term ART experienced individuals have decreased frequency of CD161-expressing gut homing CD8+ T-cells.

<p>Frequencies (expressed as percentages) of peripheral blood (PB) memory gut homing (CD45RO+ CCR9+ B7+) CD4+ (A) and CD8+ (C) T-cells expressing CD161 were determined by flow cytometry on PBMCs of HIV-infected individuals (HIV+), antiretroviral (ART) naïve (n = 18), ART experienced individuals on short-term (n = 15) and long-term treatment (n = 32), HIV controllers (n = 6) and HIV seronegative individuals (SN, n = 5). Scatter plots were used to represent the data. Horizontal lines indicate median values. Each symbol represents one individual. The red symbols represent the females in each group. Groups were compared using Kruskal-Wallis test correcting for multiple comparisons using the Dunnett´s post-test. Only significant corrected p values are shown ***p<0.0005, **p<0.005, *p<0.05. Spearman's rank correlation between PB gut homing CD4+ CD161+ T-cells and plasma viral load (pVL) in the ART naive group (B). Gender was color-coded as follows: red dots, women and black dots, men.</p