Lipopolysaccharide Antigens of Pseudomonas aeruginosa and Design of Novel Vaccines

摘要

The antigenic lipopolysaccharides (LPS) of the cell coats of five of the seven Fisher immunotype strains of the Gram-negative pathogen Pseudomonas aeruginosa have been characterized structurally by chemical methods involving degradation techniques, and by physical methods, notably high-field NMR spectroscopy. Of the seven Fisher types, the O-Chain structures of five of the types have been characterized in our laboratories. Partial structures for the remaining two types have been elucidated. The Gram-negative bacterium Pseudomonas aeruginosa is ubiquitous in its occurrence and is characterized by a very wide variety of strains as determined by conventional serotyping methods. Although healthy individuals normally have a high innate resistance to infection by Pseudmonas aeruginosa as a result of effective combat by matured antibodies, the organism is an opportunistic pathogen; virulent strains lead to dangerous, often fatal, infections in human subjects whose natural resistance has been lowered. Conventional treatment with antibiotics effective against Gram-positive organisms is of little value, as such therapeutic agents are unable to penetrate the lipopolysaccharide layer that forms a thick, hydrophobic outer coating of the cells in Gram-negative organisms. In view of the limited effectiveness of conventional antibiotic agents for combat of Pseudomonas infections, immunotherapeutic methods have been explored as an alternative method.