Evidence that the receptor for soluble CD14:LPS complexes may not be the putative signal-transducing molecule associated with membrane-bound CD14.
Membrane-bound CD14 acts as a receptor for lipopolysaccharide (LPS) on monocytes/macrophages and neutrophils. Studies have suggested that the activation of monocytes/macrophages by the binding of LPS to membrane-bound CD14 may require the association of a signal-transducing molecule with membrane-bound CD14. The observation that non-CD14 expressing cells, such as endothelial cells, can nevertheless be activated by a complex of LPS and a soluble form of CD14 (sCD14) suggests that the receptor for this complex may be identical to the signal transducing molecule associated with membrane-bound CD14. The studies described show that two CD14-specific MoAb are able to block the LPS-induced activation of endothelial cells but do not affect the response of monocytes to LPS. This suggests that the interaction of the sCD14:LPS complex with endothelial cells is distinct from the interaction of membrane-bound CD14 with its putative signal-transducing molecule.
Haziot
A
A
Division of Molecular Medicine, North Shore University Hospital, Cornell University Medical College, Manhasset, NY 11030, USA.
Katz
I
I
Rong
G W
GW
Lin
X Y
XY
Silver
J
J
Goyert
S M
SM
D000911:Antibodies, Monoclonal; D004730:Endothelium, Vascular / Q000187:drug effects / Q000276:immunology*; D017261:Glycosylphosphatidylinositols; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D018950:Lipopolysaccharide Receptors / Q000276:immunology / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000378:metabolism* / Q000494:pharmacology; D009000:Monocytes / Q000187:drug effects / Q000276:immunology*; D011971:Receptors, Immunologic / Q000502:physiology*; D012475:Salmonella; D015398:Signal Transduction / Q000502:physiology*; D012995:Solubility; D015854:Up-Regulation
D000911:Antibodies, Monoclonal; D017261:Glycosylphosphatidylinositols; D018950:Lipopolysaccharide Receptors; D008070:Lipopolysaccharides; D011971:Receptors, Immunologic; D018799:Intercellular Adhesion Molecule-1