Abstract
Phagocytic cells, the front-line defense against bacterial invasion, have enzymes that deacylate and dephosphorylate the toxic lipid A moiety of gram-negative bacterial lipopolysaccharide (LPS, also called endotoxin). These enzymes may detoxify LPS without destroying its immunogenicity or antigenicity--in fact, the polysaccharide region of LPS often resists degradation in vivo and retains its antigenic epitopes for long periods of time. The net result, detoxification of LPS with preservation of its immunogenic and antigenic properties, may prevent excessive inflammatory responses while promoting the development of antibacterial immunity.