EFFECTS OF LIPOPOLYSACCHARIDE BINDING PROTEIN ON TOLL-LIKE RECEPTOR 4(TLR4) PATHWAY IN ALVEOLAR MACROPHAGES OF ACUTE LUNG INJURY INDUCED BY LIPOPOLYSACCHARIDE (LPS) IN RAT / 解放军医学杂志

ABSTRACT

To explore the effects of lipopolysaccharide binding protein (LBP) on toll like receptor 4 (TLR4) pathway in alveolar macrophages of acute lung injury induced by lipopolysaccharide (LPS) in rats. The TNF ?concentration, IL 1? and IL 18 mRNA expression in alveolar macrophages (AM?) from rats challenged with LPS or LPS + LBP or LPS+LBP+multi LBP antibody (mLBPab) were measured with ELISA and semi quantative reverse transcription polymerase chain reaction (RT PCR) respectively. The expression of TLR4 was determined with RT PCR and Western blot. The results showed that the TNF ? concentration ,IL 1?, IL 18 mRNA expressions and TLR4 expression were increased significantly in the AM? stimulated with LPS +LBP compared with single LPS stimulation group. However, mLBPab blocked these effects. It is suggested that LBP could enhance the trans membrane transduction function of LPS via TLR4 in rat AM? and these might be the main reason that LBP could enhance the inflammatory activity of LPS, and LBP antibody could be used to alleviate such morbid conditions such as SIRS, acute lung injury, ARDS, and septic syndrome.