Fig. 4

Levels of immune activation and exhaustion are increased in HCV/HIV coinfected injecting drug users (IDU). Percentages of HLA-DR/CD38 positive peripheral CD4⁺ T cells and CD8⁺ T cells (a) of: healthy donors (HD); MEU IDU; HCV monoinfected IDU and HIV/HCV coinfected DU. RTL was measured in the first available sample since study entry (t = 2) and the most recent sample (t = 2) of MEU, HCV monoinfected and HIV/HCV coinfected DU. b Median fluorescent intensity (MFI) of PD1 in peripheral CD4⁺ T cells and CD8⁺ T cells. Box and whisker plots show the median and 10–90 percentiles. The Wilcoxon-signed rank test was used for comparison within groups with the same individuals (MEU, HCV and HIV/HCV). Kruskall-Wallis test were used to compare between groups followed by post hoc Mann-Withney U tests