Lipopolysaccharide-binding protein as a major plasma protein responsible for endotoxemic shock.
Because lipopolysaccharide (LPS)-binding protein (LBP) sensitizes monocytes to LPS in vitro, it has been suggested that LBP initiates host defenses against Gram-negative bacteria. The role of LBP in vivo, and particularly in endotoxemic shock, is unknown, however. Therefore an IgG against murine LBP was prepared. It was found to neutralize binding of LPS and subsequent activation of murine macrophages in vitro. This anti-LBP protected mice against the lethal effect of LPS when given at the same time as LPS challenge, but it failed to protect mice when delayed 15 min after LPS challenge. The same preparation was also effective after challenge with lipid A but not after challenge with Staphylococcus aureus enterotoxin. The protection was correlated with a strong decrease of circulating tumor necrosis factor. These data demonstrate that in vivo LBP is a major mediator of the lethal effects of endotoxemia.
Gallay
P
P
Department of Internal Medicine, CHUV-1011 Lausanne, Switzerland.
Heumann
D
D
Le Roy
D
D
Barras
C
C
Glauser
M P
MP
D000209:Acute-Phase Proteins / Q000378:metabolism*; D000818:Animals; D001853:Bone Marrow; D002352:Carrier Proteins / Q000097:blood* / Q000302:isolation & purification; D002852:Chromatography, Ion Exchange; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli; D006412:Hematopoietic Stem Cells; D015151:Immunoblotting; D007074:Immunoglobulin G / Q000494:pharmacology; D007700:Kinetics; D008070:Lipopolysaccharides / Q000378:metabolism*; D008264:Macrophages / Q000378:metabolism*; D008562:Membrane Glycoproteins; D051379:Mice; D008815:Mice, Inbred Strains; D012772:Shock, Septic / Q000097:blood*; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D000099231:Lipopolysaccharide-Binding Protein
D000209:Acute-Phase Proteins; D002352:Carrier Proteins; D007074:Immunoglobulin G; D008070:Lipopolysaccharides; D008562:Membrane Glycoproteins; D014409:Tumor Necrosis Factor-alpha; D000099231:Lipopolysaccharide-Binding Protein