Adjuvant activity of QS-21 for experimental E. coli 018 polysaccharide vaccines.
Three types of experimental vaccines containing O-side-chain polysaccharide from the enterotoxigenic strain Escherichia coli 018 were evaluated. The immunogenicity of free O-polysaccharide (PS), a polysaccharide-diphtheria toxoid conjugate (PS-conj), and detoxified lipopolysaccharide (dLPS) was tested in female ICR mice, either alone or in combination with QS-21, a purified saponin adjuvant derived from the bark of the tree Quillaja saponaria Molina. Both the number of individual mice responding and the titres of O-polysaccharide specific antibodies in pools of sera were increased by the addition of QS-21. The immune response to both O-specific polysaccharide and carrier was primarily IgM and IgG1. The addition of QS-21 not only increased the level of IgG1, but also had a significant adjuvant effect on antigen-specific IgG2a, IgG2b and IgG3.
Coughlin
R T
RT
Cambridge Biotech Corporation, Worcester, MA 01605, USA.
Fattom
A
A
Chu
C
C
White
A C
AC
Winston
S
S
D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000818:Animals; D001428:Bacterial Vaccines / Q000276:immunology*; D004926:Escherichia coli / Q000276:immunology*; D022361:Escherichia coli Vaccines; D005260:Female; D008070:Lipopolysaccharides / Q000276:immunology*; D051379:Mice; D008813:Mice, Inbred ICR; D011135:Polysaccharides, Bacterial / Q000276:immunology*
D000276:Adjuvants, Immunologic; D001428:Bacterial Vaccines; D022361:Escherichia coli Vaccines; D008070:Lipopolysaccharides; D011135:Polysaccharides, Bacterial