[Biological characterization of Bacteroides intermedius specific monoclonal antibody].

One monoclonal antibody (BIF6) directed against Bacteroides intermedius Group I was developed by hybridoma technology. In the present study, we used culture medium from BIF6 antibody-producing cells to characterize the antibody. Its reactivity against B. intermedius (Group I, II), B. gingivalis, B. corporis, B. melaninogenicus, B. loescheii, and B. asaccharolyticus was detected by the enzyme-linked immunosorbent assay. BIF6 monoclonal antibody specifically reacted with B. intermedius Group I, but not with B. intermedius Group II. Also, the BIF6 did not react with other black-pigmented Bacteroides. Since BIF6 antibody reacted with some clinical isolates from subgingival plaques of adult periodontal patients, we suggest that this antibody may be useful as a tool in the clinic to identify B. intermedius Group I. Specific antigen of B. intermedius Group I recognized by BIF6 antibody was located on the outer membrane of the organism. And the specific antigen was inactivated by treatment for 20 min at 80 degrees C and at pH2 and 12. Also the antigen was sensitive to trypsin treatment.