COPD (chronic obstructive pulmonary disease) is one of the most common fatal diseases worldwide. In Germany alone, there are about 3-5 million patients affected. COPD includes both chronic obstructive bronchitis and emphysema. Both represent irreversible changes of the central and lower respiratory tract which are accompanied by coughing, mucus production and difficulty in breathing.
The increased production of mucus is induced by the immigration of neutrophilic granulocytes and macrophages. This can be further accompanied by the destruction of the bronchial epithelium and the alveolar septae and thus lead to emphysema. The disease progresses in episodic bursts; although it cannot be cured, early diagnosis and appropriate therapy allow it to bring the symptoms under control.
Macrophages play a central role in the air passages and the lung periphery (the alveoli). Macrophages originate in the bone marrow. Before entering the blood stream, these cells differentiate through precursor myelomonocytes to monocytes which migrate into the tissues and are then called macrophages. One of the major tasks of macrophages is to take up foreign particles, like bacteria, viruses, and aerosol particles, by phagocytosis.