Antigenic differences between Brucella abortus and Brucella melitensis recognized by a monoclonal antibody.

By means of somatic hybridization of spleen cells from BALB/c mice inoculated with Brucella abortus and of a line of murine myeloma, a monoclone was obtained producing an antibody which specifically recognizes an epitope of Brucella abortus by means of the agglutination reaction. This epitope is not only on the surface of the homologous strains but on all the Brucella abortus biotype I, on the Brucella melitensis biotype II and on the Brucella suis biotype II tested. On the contrary it is not present on the Brucella melitensis biotype I and in just one of six Brucella melitensis biotype III. Very few strains of the other biotypes of Brucella suis were tested: the results are often negative.

Sensitivity of 115 strains of the genus Brucella to some antibiotics (cephalosporins, ureidopenicillins and aminoglycosides).

The Authors tested piperacillin, azlocillin, aztreonam, cefotaxime, ceftizoxime, ceftriaxone, cefotetan, moxalactam, gentamicin, sisomicin and dibekacin, on about 120 strains of the genus Brucella, using as control drugs tetracycline, streptomycin and rifampicin. Cefotaxime, ceftizoxime, gentamicin, and sisomicin exhibited antibrucella activity comparable to that of tetracycline and just a little superior to that of rifampicin. Among the aminoglycosides tested, gentamicin, sisomicin and dibekacin were, in decreasing order, more active than streptomycin. For all the other drugs tested there was a large variability among the brucella strains, with roughly a peak of activity on the strains which have a history of repeated in vitro passages.