Detection of strain-specific antigenic epitopes on the lipo-oligosaccharide of Haemophilus parasuis by use of monoclonal and polyclonal antibodies.
OBJECTIVE
To investigate the antigenic diversity of lipo-oligosaccharides of Haemophilus parasuis.


METHODS
Immunoblot assays were done with monoclonal and polyclonal antibodies on whole-cell lysates. Individual colonies of H parasuis strains H 54, H 53, and H 128 were tested for reactivity with lipo-oligosaccharide-specific monoclonal antibodies after a single passage on chocolate agar, and colonies of strain H 54 were analyzed after 10 passages. Colony blot tests were used to screen H parasuis strains for spontaneously occurring antigenic variation in their lipo-oligosaccharides.


RESULTS
Eight H parasuis strains were separated into 4 lipo-oligosaccharide serovars on the basis of immunoblot reactions with 3 polyclonal rabbit antisera. Nine monoclonal antibodies against lipo-oligosaccharides of a lipo-oligosaccharide-serovar I strain reacted with all tested serovar I strains but failed to react with other H parasuis strains.


CONCLUSIONS
Variations in the antigenic reactivity after 1 or 10 passages on chocolate agar were not observed. The serovar I lipo-oligosaccharide strains included virulent as well as avirulent H parasuis strains, indicating that these epitopes do not correlate directly with virulence properties of H parasuis.
Zucker
B A
BA
Department of Veterinary Microbiology and Parasitology, Louisiana State University, Baton Rouge, 70803, USA.
Baghian
A
A
Traux
R
R
O'Reilly
K L
KL
Storz
J
J
D000818:Animals; D000906:Antibodies; D000911:Antibodies, Monoclonal; D000940:Antigenic Variation; D000942:Antigens, Bacterial / Q000737:chemistry*; D004591:Electrophoresis, Polyacrylamide Gel; D000939:Epitopes / Q000032:analysis*; D005260:Female; D006190:Haemophilus / Q000145:classification / Q000254:growth & development / Q000276:immunology*; D006192:Haemophilus Infections / Q000382:microbiology / Q000662:veterinary; D015151:Immunoblotting; D008070:Lipopolysaccharides / Q000737:chemistry* / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C / Q000276:immunology; D011817:Rabbits / Q000276:immunology; D013552:Swine; D013553:Swine Diseases; D014774:Virulence
D000906:Antibodies; D000911:Antibodies, Monoclonal; D000942:Antigens, Bacterial; D000939:Epitopes; D008070:Lipopolysaccharides