We also aim to assess the role of the macrophage precursor (monocyte) and neutrophils in the blood. We will also assess lymphocyte/monocyte interaction. We will do this as the lymphocyte may be involved in the initial recruitment of inflammatory cells. We will also assess the role of cytokines involved with monocyte/macrophage/neutrophil migration in induced sputum as well as the role of induced sputum in the migration of monocytes and neutrophils into the lung. Our aim is to link the initial changes in blood to the changes causing disease in the lungs. We aim to examine cellular responses in four groups of subjects, namely (i) non-smoking controls, (ii) smokers without clinical evidence of COPD or asthma, (iii) smokers with COPD (iv) asthmatic patients.