Diaphragm biopsies from 7 COPD patients (forced expiratory volume in predicted) and 5 non-COPD patients (forced expiratory volume in 1 s 105 predicted) were obtained. Cryosections of these biopsies were stained with antibodies against the costameric proteins of the focal adhesion complex (vinculin, talin and integrin- 1), the dystroglycan complex (dystrophin and -dystroglycan) and the spectrin-based membrane cytoskeleton ( -spectrin). Furthermore, in these cryosections, the basal membrane protein laminin was stained. Results: We found no differences in the distribution and staining intensity of the costameric proteins of the focal adhesion complex, the dystroglycan complex and the spectrin-based membrane cytoskeleton in the diaphragm between the COPD and the non-COPD patients.