In the alveolar walls, the number of CD8+T-cells was higher in smokers with COPD [median(range) 6.7(2.0-17.5) cells/mm] than in those without COPD [3.2(0.8-8.8) cells/mm; p=0.006] and non-smokers [1.7(0.2-5.1) cells/mm; p<0.001]. The gene discussed is CD8A; the disease is chronic obstructive pulmonary disease.