RT Journal Article
SR Electronic
T1 Distribution of surfactant proteins in proximal and distal airways
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP P2045
VO 44
IS Suppl 58
A1 Ekaterina Mirgorodskaya
A1 Anna Bredberg
A1 Jamshid Pourazar
A1 Per Larsson
A1 Robert Linder
A1 Anna-Carin Olin
A1 Annelie Behndig
YR 2014
UL http://erj.ersjournals.com/content/44/Suppl_58/P2045.abstract
AB Surfactant protein (SP) A and D are large multimeric proteins that belong to the collectin-family. Changes in SP-A and/or SP-D levels have been reported in acute as well as chronic inflammation, however, little is known about their distribution along the airways. The majority of existing SP-A and SP-D data comes from bronchoalveolar lavage (BAL) studies. The airway's area covered by BAL collection can vary strongly depending on the sampling volumes and thus can represent both proximal and distal airways. Both surfactant proteins are involved in the innate immune defense and their pulmonary distribution might be important for providing optimal host-defense. We hypothesized that SP-A and SP-D have different pulmonary distribution between central and peripheral airways. To test this hypothesis we compared protein levels in bronchial wash (BW) and BAL samples, which represent different areas of the lungs.Methods: BW and BAL were sampled from 15 healthy individuals. Differential cell count was performed for all samples. Total protein concentrations were determined by Bradford assay, SP-A and SP-D concentrations by immunoassay.Results: Significantly different counts for neutrophils and macrophages were observed in BW than BAL (p<0.001), confirming samples' different origin in the lung. The ratio of SP-A/SP-D was 24 in BW and 16 in BAL. In average BAL showed higher levels of SP-A as well as SP-D, statistical significant difference for SP-D (p<0.001).Conclusion: SP-A and SP-D have different pulmonary distribution. SP-A is more evenly spread in proximal and distal airways, whereas SP-D is present at significantly higher levels in distal airways.