Rabbit immunoglobulin (Ig)M and IgG antibodies to Brucella abortus and Bordetella pertussis were isolated as purified products and their specific secondary biological activities were compared. IgM antibodies were found to be more active than IgG proteins in inducing agglutination and sensitization of B. abortus for the complement-dependent bactericidal effect and in inhibiting B. pertussis-indu...

Brucella spp. is the aetiological agent of brucellosis, a serious contagious disease that results in reproductive failure and that has profound public health significance be‐ cause of its zoonotic characteristics. This disease also is responsible for a high eco‐ nomic impact associated with the application of prevention, surveillance and test-andslaughter programmes in animals by national autho...

A low-molecular-weight recombinant Brucella abortus protein reactive with antibodies from a variety of naturally and experimentally infected hosts and T lymphocytes from experimentally infected mice was identified and given the designation BA14K. The gene encoding BA14K was cloned and characterized, and the predicted amino acid sequence of this immunoreactive protein showed no significant homol...

Experiments were performed with BALB/c mice to elucidate the roles of humoral and cell-mediated immune responses in the acquisition of protective immunity to Brucella ovis and to compare infection immunity with immunity developed through vaccination with a hot saline extract (HS) of B. ovis. Mice convalescing from a primary infection with B. ovis displayed a high level of resistance to reinfect...

Due to drawbacks of live attenuated vaccines, much more attention has been focused on screening of Brucella protective antigens as subunit vaccine candidates. Brucella is a facultative intracellular bacterium and cell mediated immunity plays essential roles for protection against Brucella infection. Identification of Brucella antigens that present T-cell epitopes to the host could enable develo...

The role of Brucella infections in cattle abortions was investigated in 914 females from 124 herds. Animals were tested for exposure to Brucella species and history of abortion over the past three years. Sera were tested using the Rose Bengal test (RBT) and competitive enzyme-linked immunosorbent assay (c-ELISA). Of 886 females tested, 189 were positive on RBT, and 154 (81.5%) were confirmed by...

BACKGROUND Different serological tests are used in serologic diagnosis of brucellosis. The most widely used of these are Standard Tube Agglutination and Coombs anti-brucella tests. Whereas ELISA Ig M and Ig G tests have been in use for a long time, immuncapture agglutination test has been recently introduced and used in serological diagnosis. The aim of this study was to compare diagnostic valu...

A total of 167 blood samples from aborting sheep were collected from nine different villages and the serum samples were tested for the presence of Brucella melitensis antibodies by a serum agglutination test and Chlamydophila abortus antibodies by ELISA. Seventy-one (40.11%) and nine (5.38%) serum samples were found to be positive for B. melitensis and C. abortus, respectively. These results ma...

Brucella organisms are facultative intracellular bacteria that may infect many species of animals as well as humans. The smooth lipopolysaccharide (S-LPS) has been reported to be an important virulence factor of these organisms, but the genetic basis of expression of the S-LPS O antigen has not yet been described. Likewise, the role of the O side chain of S-LPS in the survival of Brucella has n...

A flock of sheep, known to be infected with the "FSA" mutant of Brucella melitensis Rev. 1, was examined serologically and bacteriologically to determine whether any relationship existed which would help in the control of this infection in the field. An attempt was also made to determine whether vertical transmission occurred. Twenty-one out of 62 sheep were bacteriologically positive. The best...