Table 1.
Age and Clinical Features of Study Participants (N = 48).
Figure 1.
Low ecto-ADA expression correlates with high levels of activation markers.
(a) Representative flow cytometry data of surface staining for ecto-ADA and CD8 molecules on T cells 4 days after stimulation with an allogeneic transformed B-cell line. Comparison between %ADA+ within the CD8+ T cell subset from HIV+ donors with low (top) and high activation (bottom) levels, defined by activation marker CD38 (2.1% and 18.2%, respectively). CD8+ T cells with low %CD38 had greater ecto-ADA expression (30.2%), as compared to those with high %CD38, who showed lower ADA (13.3%). (b) Representative histogram comparing the same donors as in panel (a). The dark lines represent the donor with high activation (18.2%), compared to the donor with low activation (2.1%). (c) Statistical analyses indicating a strong negative relationship between ecto-ADA expression and percentages of CD38+ and HLA-DR+ (r = −0.5441, p<0.0001), as well as number of CD38 molecules (r = −0.4766, p = 0.0004). (d) Significant positive correlation between CD8+ADA+ and CD8+ telomerase activity (r = 0.4012, p<0.0069).
Figure 2.
LRRN3 mRNA expression is associated with increased expression of CD38+ and HLA-DR+.
(a) Ex vivo CD8+ T cells from HIV+ donors were isolated using RosetteSep CD8+ T cell enrichment cocktail from whole blood. LRRN3 transcription in CD8+ T cells was compared for HIV+ donors with high and low levels of activation, defined by CD38 and HLA-DR. 36B4 was used as the housekeeping gene. There was a strong negative relationship between LRRN3 mRNA and percentages of CD38+ and HLA-DR+ cells (r = −0.36012, p = 0.0192). (b) Positive correlation between LRRN3 mRNA and CD3+ telomerase activity (r = 0.5988, p<0.0001) and CD8+ telomerase activity (r = 0.2724, p = 0.11). (c) Positive relationship between LRRN3 mRNA and %CD28+ within the CD8+ T cell subset (r = 0.3782, p = 0.0161), suggesting a potential modulatory role of LRRN3 on CD28 surface expression.
Figure 3.
Telomerase activity is inversely correlated with activation biomarkers in T cells.
(a) Representative telomeric repeat amplification protocol (“TRAP”) gel of CD8+ T cells from individual HIV+ donors tested 4 days after activation with anti-CD2/CD3/CD28 microbeads. Lane 1 (+) shows telomerase activity of the Jurkat T cell line. All telomerase activity values from each donor were normalized relative to this positive control. The CD8+ T cell telomerase activity was compared to the percent CD38+. Low %CD38 CD8+ T cells (lanes 2 and 3, with 1.8% and 2.7% CD38+, respectively) have significantly more telomerase activity, indicated visually by the darker bands, than CD8+ T cells with high %CD38+ (lane 1, with 18.5% CD38+). (b) Telomerase activity of CD3+ T cells and the CD8+ T cell subset from HIV+ donors was compared to the %CD38+HLADR+. Statistical analyses showed a strong negative relationship between the %CD38+DR+ cells and telomerase activity of both CD3+ (r = −0.5531, p = 0.0001) and a trend with CD8+ T cells (r = −0.2429, p = 0.1149).