Endotoxin interactions with lipopolysaccharide-responsive cells

Recent work has identified two proteins that work together to enable many c ell types to respond to endotoxin. These two proteins, lipopolysaccharide ( LPS) binding protein (LBP) and CD14, also participate in cellular internali zation of endotoxin, which may occur independently of cellular activation. Current work with antibodies to LBP and CD14 as well as "knockout" mice in the context of LPS-initiated endotoxic shock suggests that inhibition of th is pathway could be therapeutically useful. These observations point to the need to identify new molecules that mediate LPS-initiated transmembrane si gnaling and internalization of LPS-protein complexes.