CD8A and chronic obstructive pulmonary disease: In small airways the number of CD8+T-cells was higher in severe COPD [median(range) 450(150-558) cells/mm2] than in mild/moderate COPD [178(13-389) cells/mm2; p=0.02], smokers without COPD [179(72-378) cells/mm2; p=0.01] and non-smokers [median(range) 90(25-265) cells/mm2; p=0.002].