The localization of SP-B and influences of lipopolysaccharide on it.

Objective: Surfactant protein B (SP-B) is the only essential protein component of lung surfactant, the relationship between localization and function is very close. The localization of rat SP-B and influences of lipopolysaccharide (LPS) on it were investigated.

Materials And Methods: The localization of SP-B protein in lung tissue was detected by immunofluorescence after challenged with intratracheal instillation of LPS. The constructed recombinant plasmid pEGFP-N2-SP-B was transfected with CCl-149 cell lines by liposome to explore the localization of SP-B in alveolar type II epithelial cells. Furthermore, the expression and function of SP-B were analyzed with LPS stimulating.

Results: The proteins SP-B and SP-C showed the same pattern of expression in normal lung, and distributed in the alveolar cavity, LPS can directly affect the expression of SP-B in vivo, contrast to SP-B, the LPS-induced influences on SP-C is little. SP-B had the membrane embedded features and localized on the cell surface of CCL149 in vitro, but was influenced by LPS.

Conclusions: It is confirmed that the expression and membrane function of SP-B were decreased by stimulating LPS in lung tissue and alveolar type II epithelial cells.