Cross-reactivity between the mannan of Candida species, Klebsiella K24 polysaccharide and Salmonella C1 and E O-antigens is mediated by a terminal non-reducing beta-mannosyl residue.
Rat monoclonal antibody MASC1-MR9 (MR9) binds to a mannan of Candida species and the O-antigenic polysaccharides of Salmonella bacteria of serogroups C1 (CO) and E (EO). Mannan and glycoconjugates comprising BSA and O-antigen polysaccharides, decasaccharide-BSA (CO-BSA) or trisaccharide-BSA (EO-BSA), inhibited each other's reactivity with MR9. The saccharides beta-D-Manp-(1-->6)-alpha-D-Manp-1-OMe, beta-D-Manp(1-->3)-alpha-D-Manp-1-OMe, beta-D-Manp(1-->2)-alpha-D-Manp-1-OMe (corresponds to the terminal non-reducing end of Salmonella serogroup C1 O-antigen) and beta-D-Manp(1-->4)-alpha-L-Rhap(1-->3)-alpha-D-Galp-1-O-p-++ +trifluoroacetamido aniline (corresponds to the backbone of Salmonella serogroup E O-antigen) inhibited the binding of MR9 to these antigens whereas alpha-D-Manp(1-->3)-alpha-D-Manp-1-OMe and alpha-D-Manp(1-->4)-alpha-L- Rhap-1-O-p-nitrophenyl did not. Saccharides (3-10 residues) of mammalian origin with terminal and internal Manp alpha-1-->2, Manp alpha-1-->3 and Manp alpha-1-->6 residues also failed to inhibit at any concentration. None of the saccharides with internal beta-mannosyl residue was able to inhibit the MR9 antibody. Monosaccharides D-mannose, beta-D-Manp-1-OMe and 1,5 anhydro-D-mannitol inhibited the MR9 monoclonal antibody whereas alpha-D-Manp-1-OMe, beta-D-Glcp-1-OMe, and beta-D-Galp-1-OMe did not. In addition a Klebsiella K24 capsular polysaccharide containing a beta-D-Manp(1-->4)-alpha-D- GlcA (GlcA, glucuronic acid) as a structural element possessed an inhibitory activity. MR9 therefore recognizes an epitope within beta-mannose monosaccharide residues at the terminal non-reducing ends of carbohydrate chains in mannan, and polysaccharides in Salmonella serogroups CO and EO and Klebsiella K24.
Nnalue
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Department of Immunology, Microbiology, Pathology and Infectious Diseases, Karolinska Institute, Huddinge University Hospital, Sweden.
Weintraub
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Oscarson
S
S
Lindberg
A A
AA
D000911:Antibodies, Monoclonal / Q000276:immunology; D000918:Antibody Specificity; D000942:Antigens, Bacterial / Q000276:immunology*; D000946:Antigens, Fungal / Q000737:chemistry*; D002175:Candida / Q000276:immunology*; D002240:Carbohydrate Sequence; D003429:Cross Reactions; D006001:Glycoconjugates / Q000276:immunology; D007709:Klebsiella / Q000276:immunology*; D008351:Mannans / Q000276:immunology*; D008969:Molecular Sequence Data; D019081:O Antigens; D009844:Oligosaccharides / Q000737:chemistry / Q000276:immunology; D011135:Polysaccharides, Bacterial / Q000276:immunology*; D012475:Salmonella / Q000276:immunology*
D000911:Antibodies, Monoclonal; D000942:Antigens, Bacterial; D000946:Antigens, Fungal; D006001:Glycoconjugates; D008351:Mannans; D019081:O Antigens; D009844:Oligosaccharides; D011135:Polysaccharides, Bacterial