ABSTRACT
The effects of endotoxin on the animal host provide a paradigm for microbe-host interactions in general. Thus, the ability of the lipopolysaccharides (LPS) isolated from the gram-negative bacterial envelope to trigger a broad spectrum of cellular and extracellular responses in the intact host as well as in vitro has served as a model for the dissection of antimicrobial defense systems that constitute innate immunity. The extraordinary efficiency and effectiveness of these systems is well illustrated by the fact that we are generally unaware of the daily penetration of our epithelial barriers by microbial inhabitants of our internal and external environment and their products, including cell-free LPS. lipopolysaccharide-binding protein is an acute phase plasma protein produced in the liver that serves a primary role in transmitting the LPS signal to responsive host cells.
