title: Preparation and characterization of detoxified lipopolysaccharide-protein conjugates.
abstract: Alkaline treatment of Pseudomonas aeruginosa type 5 lipopolysaccharide (LPS) resulted in reduced toxicity as measured by both the Limulus amoebocyte assay and the rabbit pyrogenicity test. Chemical analysis of the deacylated LPS (D-LPS) revealed that ester-linked fatty acids were removed while the amide-linked fatty acids remained intact. The neutral and amino sugar compositions for native LPS and D-LPS were identical within experimental error. Antigenic determinants for complement-dependent human opsonic antibody were retained under these deacylation conditions. To enhance its immunogenicity, D-LPS was covalently coupled to Pseudomonas pili and the 1,4-diaminobutyl derivatives of Pseudomonas exotoxin A and tetanus toxoid. Quantitative amino sugar analyses revealed that 2.6 and 3.2 mol of D-LPS were covalently bound to aminobutyl Pseudomonas exotoxin A and aminobutyl tetanus toxoid, respectively. Gel electrophoresis data indicated at least 1 mol of D-LPS covalently bound per pilus subunit protein. Initial immunologic data indicated that antibody against D-LPS could be induced when the D-LPS is covalently attached to protein carriers.
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002241:Carbohydrates / Q000032:analysis; D000939:Epitopes; D005227:Fatty Acids / Q000032:analysis; D006737:Horseshoe Crabs; D008070:Lipopolysaccharides / Q000302:isolation & purification* / Q000633:toxicity; D008565:Membrane Proteins / Q000302:isolation & purification* / Q000633:toxicity; D011550:Pseudomonas aeruginosa / Q000276:immunology*; D011817:Rabbits
chemical_list: D000596:Amino Acids; D002241:Carbohydrates; D000939:Epitopes; D005227:Fatty Acids; D008070:Lipopolysaccharides; D008565:Membrane Proteins