Figure 1

(UPPER PANEL) Representative Western blots of SP-B, SP-C and their proforms. Specific bands are marked with arrows. The frequency at which bands were detected at the respective molecular weights is listed in Table 2. Some blots also showed additional bands which were the residuals from previous incubations of the same blots with the other antibody (pro-SP-C was detected after the blot was incubated with SP-C, and SP-B after Pro-SP-B). In none of the patients pro-SP-C was detected. The arrow indicates the positive control for pro-SP-C in a lavage of a patient with a SP-C mutation and the presence of pro-SP-C in his lavage. (MIDDLE PANEL) Initially in samples CF-20-1 and CF-21-1, no SP-C was detected. Additional BALF samples from the same patients at later time points were available and run in addition. SP-C was only detected in samples CF 20-2 and CF 21-2. (LOWER PANEL) Interestingly samples CF 20-1 and CF 21-1 showed a clear positive reaction with the pro-SP-C-antibody at a molecular weight of 3 – 4 kDa. This might be fragments of pro-SP-C which reacted to the antibody or non-specific bands (arrow). All other bands in blot C) were non specific (#). * band from previous incubation # non-specific reaction.