Observational StudyHow Smoking Causes COPD: Examination of Immune System Changes

A breathing condition known as "chronic obstructive pulmonary disease" (COPD) caused by cigarette smoking is a major health problem. The way by which smoking leads to lung disease is uncertain. Recent research done in animals provides a description of specific changes (that is a reduction) in these immune cell types as a result of cigarette smoke exposure. The study you have been asked to participate in is a pilot study to see if similar changes occur in humans who smoke. The purpose of this study is to evaluate this new method of testing blood in 3 groups of 10 people: normal non-smoking subjects, subjects who smoke with no history of lung disease and subjects who smoke and have smoking related COPD.