CD8⁺ T-Cell Differentiation and HIV-1 Disease Progression

<div><p>(A) Distribution of the CD8⁺ T-cell population in differentiated subsets (CD28⁺/CD27⁺ early, CD28⁻/CD27⁺ intermediate, and CD28⁻/CD27⁻ late) through the course of HIV-1 infection. Abbreviations: H, healthy (<i>n</i> = 15); A, acute HIV infection (<i>n</i> = 11); C, chronic HIV infection nonprogressor (no ART; <i>n</i> = 14); P, chronic HIV infection with signs of disease progression (no ART; <i>n</i> = 10). Statistics: * <i>p</i> < 0.0001 with the ANOVA test and <i>p</i> < 0.005 between each group.</p> <p>(B) Percentages of CD27⁻ CD8⁺ T-cells that are specific for HLA-B8 HIV (nef) or HLA-A2 CMV in HIV-1-infected individuals at different stages of infection. Statistics: ** <i>p</i> < 0.005 with the nonparametric Mann–Whitney test.</p> <p>(C) Inverse correlation between CD4⁺ T-cell counts and percentage of highly differentiated CD27⁻ cells in the whole CD8⁺ T-cell population of HIV-1-infected donors during chronic infection (untreated nonprogressors and progressors). The <i>p</i> value was obtained using the nonparametric Spearman rank correlation test.</p></div

CD8⁺ T-Cell Differentiation and Senescence

<div><p>(A) Expression of the replicative senescence-associated marker CD57 on antigen-experienced CD8⁺ T-cell subsets. The percentage and mean fluorescence intensity for the CD57⁺ cells are shown for one single donor. Data on several donors (HIV-1-infected or healthy) are also shown (<i>n</i> = 24).</p> <p>(B) Expression of CD57 on CD8⁺ T-cells (whole population or antigen-specific) from acute to postacute (on ART) HIV-1 infection.</p> <p>(C) CD69 expression and CFSE proliferation profile for CD8⁺ T-cell subsets gated on the basis of CD57 and CD27 expression following stimulation with anti-CD3 antibodies. PBMCs were analysed for CD69 expression after 18 h and CFSE labeling after 6 d. Percentages of proliferating cells (with background subtracted) are indicated. Representative results from three experiments (one HIV-infected and two healthy donors) are shown.</p> <p>(D) Telomere length measurement by flow FISH on naïve and antigen-experienced CD8⁺ T-cell subsets FACS-sorted on the basis of CD57, CD27, CCR7, and CD45RA expression. The average length of telomeres was obtained by substracting the mean fluorescence of the background control (no probe; open histogram) from the mean fluorescence obtained from cells hybridised with the FITC-labeled telomere probe (gray histogram). Representative results from two experiments (on healthy donors) are shown.</p> <p>(E) CD57 and perforin expression in the CD8⁺ T-cell population dissected into naïve (CD27^+high, perforin-negative), antigen-experienced CD27⁺ (perforin^low), and antigen-experienced CD27⁻ perforin^low or perforin^high subsets. The percentage and mean fluorescence intensity for the CD57⁺ cells are indicated.</p> <p>(F) Representative staining for perforin and CD57 in CD8⁺ T-cells from a HIV-1-infected or a healthy donor. Percentages of cells present in the top quadrants are shown.</p> <p>(G) Representative staining for perforin and CD57 in CD4⁺ T-cells from an HIV-1-infected or a healthy donor. Percentages of cells present in the top quadrants are shown.</p></div

CD8⁺ T-Cell Activation during Acute HIV-1 Infection

<div><p>(A) Percentages of activated CD38⁺ cells (gated on whole CD8⁺ T-cells, HIV tetramer-positive CD8⁺ T-cells, or whole CD4⁺ T-cells) in donors during acute HIV-1 infection and later postacute on ART (<i>n</i> = 12); healthy donors (<i>n</i> = 11) and untreated donors with nonprogressing chronic infection (<i>n</i> = 12) are also shown.</p> <p>(B and C) CD38 and Ki67 expression on CD8⁺ T-cell subsets defined by CD45RA/CD62L (B) or CD28/CD27 (C) expression, shown in one single donor from acute to postacute (on ART) HIV-1 infection. Percentages of positive cells are shown. Means (± SEM) of CD38⁺ and Ki67⁺ CD8⁺ T-cells for ten patients are also shown; statistics concern CD38 expression.</p> <p>(D) Staining for the activation marker CD38 on CMV-, EBV-, or influenza A virus-specific CD8⁺ T-cells during acute and postacute (on ART) HIV-1 infection in a single donor. Percentages of CD38⁺ tetramer-positive CD8⁺ T-cells are shown. Data on all donors (see <a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.0020020#pbio-0020020-t001" target="_blank">Table 1</a>) are also shown.</p> <p>(E) Activation (CD38 and Ki67 staining) of CMV-specific CD8⁺ T-cells or whole CD8⁺ T-cell population during acute and postacute (on ART) HIV-1 infection in a single donor. Percentages of cells present in quadrants are shown.</p> <p>Statistics: * <i>p</i> < 0.002, ** <i>p</i> < 0.01, NS = nonsignificant, with the nonparametric Mann–Whitney test.</p></div