Study of the antigenic relationships between strains of Bacteroides, intermedius, B. melaninogenicus, B. corporis, and B. denticola revealed by immunoblotting with rabbit antisera.
Antigen profiles of saccharolytic oral black-pigmented Bacteroides have been developed by Western blotting. Visual comparisons indicated extensive cross-reactions between B. intermedius, B. melaninogenicus, B. denticola, and B. corporis. Porphyromonas gingivalis, P. asaccharolyticus, and B. buccae showed less cross-reaction. Quantitation of antigenic similarity was made from densitometric scans. Calculation of the Jackard coefficient gave results of 33-72% similarity among the saccharolytic pigmented species, with the two homology groups of B. intermedius separated at 53%. Species were separated below 70%. Subtraction of the profile of a cross-reacting strain from that of the homologous strain also allowed quantitation of similarities. These similarities were lower; the range between species was 4-62%, although the two homology groups of B. intermedius still separated at 50 and 58%. Species were separated below 63%. Sera absorbed with a cross-reacting strain gave reduced reactions with the homologous strain and cross-reacting strains, indicating several common antigens among the four species. The species-specific antigens demonstrated by sera absorbed with cells of cross-reacting species were relatively few (3-6) compared with cross-reacting antigens detected by non-absorbed sera (18-28). The method appears useful to quantitate antigenic similarities among Bacteroides species and strains and allows analysis and quantitation of individual humoral responses in animals to these bacteria.
Bowden
G H
GH
Department of Oral Biology, Faculty of Dentistry, University of Manitoba, Winnipeg, Canada.
Nolette
N
N
D000818:Animals; D000942:Antigens, Bacterial / Q000032:analysis*; D001439:Bacteroides / Q000276:immunology*; D015153:Blotting, Western; D003429:Cross Reactions; D003720:Densitometry; D004591:Electrophoresis, Polyacrylamide Gel; D007106:Immune Sera / Q000276:immunology; D011817:Rabbits; D015203:Reproducibility of Results
D000942:Antigens, Bacterial; D007106:Immune Sera