FIGURE 6.

Determination of influenza A virus (IAV)-specific CD8⁺ T-cells in blood of lung-healthy controls and COPD patients. a) Percentage of CD3⁺CD8⁺IAV-tetramer(Tet)⁺ T-cells within the fraction of all CD3⁺ cells in peripheral blood mononuclear cells (PBMCs) of lung-healthy controls who are never-smokers (n=7, including one Shisha smoker) compared with ex-smokers or current smokers (n=7). b) Absolute numbers of CD3⁺CD8⁺IAV-tetramer⁺ T-cells (cells·μL⁻¹) in isolated PBMCs of COPD patients (n=9) and age-matched lung-healthy controls (n=10). Clinical characteristics can be found in table 1. c) Percentage of CD3⁺CD8⁺IAV-tetramer⁺ T-cells within the fraction of all CD3⁺ cells in PBMCs of lung healthy controls (n=9) and COPD patients (n=10). Data are presented as median (interquartile range); significance was tested using Mann–Whitney U-test. *: p<0.05, **: p<0.01.