CD4 and chronic obstructive pulmonary disease: Indeed, pathological CD8 T‐lymphocyte responses are increasingly thought to contribute to lung damage in COPD.12, 46 For example, Makris et al. found an increased frequency of CD8 T lymphocytes in induced sputum from COPD patients at the time of exacerbation, interestingly with a decreased frequency of CD4 T lymphocytes at exacerbation.47 Similarly CD8 T‐lymphocyte responses may contribute to pathology in asthma.48