Figure 5

Quaternary structure of pulmonary SP-D. The quaternary structure of SP-D in BAL: A) equal amounts of SP-D were loaded as indicated by equal band intensities of the SP-D monomer (43 kDa) in SDS page under reduced conditions and immunoblotting (upper panel A and B). The quaternary structure of SP-D in bronchoalveolar lavage from 4 healthy subjects (H) and smokers (S1) is demonstrated by blue native electrophoresis and immunoblotting (lower panel A) as well as for 3 smokers with COPD (C) (lower panel B). Due to very low SP-D levels in BAL of COPD subjects the displayed intensity of SP-D bands is not comparable between A and B.