CD247 down regulation in COPD CD8 cells was confirmed by immunofluorescent staining of bronchoalveolar lavage cells: Significantly fewer COPD CD8 cells co-expressed CD247 compared to healthy non-smoker CD8 cells (mean 88.9 vs 75.2%, p<0.05) There is down regulation of TCR signalling molecules in COPD pulmonary CD8 cells. The gene discussed is CD8A; the disease is chronic obstructive pulmonary disease.