CD8A and chronic obstructive pulmonary disease: NKT-like cells showed a similar pattern to CD8+ T-lymphocytes, namely significantly more ex vivo activation from both healthy smokers (46.0%, 17.7–58.7; p<0.001) and current smokers with COPD (33.0%, 15.4–65.3; p<0.001) compared to healthy non-smokers (7.8%, 4.3–16.9) (Figure 2B).