Protection levels in vaccinated heifers with experimental vaccines Brucella abortus M1- luc and INTA 2 (original) (raw)
Related papers
The Pharma Innovation, 2020
Bovine brucellosis, caused by Brucella abortus, is a serious zoonotic disease manifested by reproductive disorders in animals and results in huge economic losses to dairy farmers. This study was undertaken to evaluate the safety and immunogenicity of Brucella abortus S-19 reduced dose vaccine in comparison with Brucella abortus S-19 standard dose vaccine in 4-10 months old female cattle calves by measuring humoral immune responses and cell mediated immune responses. The humoral antibody responses in reduced dose group indicated absence of persistent antibody titres, whereas, those vaccinated with Brucella abortus S-19 standard dose vaccine showed persistence in antibody titres till day 240 with i-ELISA and day 150 with c-ELISA post vaccination. The IFN-γ responses in vaccinated groups were found to be diminishing till 3 years post vaccination. It is concluded that Brucella abortus S-19 reduced dose vaccine performed similar to that of Brucella abortus S-19 standard dose vaccine.
Efficacy of strain RB51 vaccine in heifers against experimental brucellosis
Vaccine, 2006
With the goal of providing an additional tool for controlling bovine brucellosis in Brazil and evaluating the full calf dose in adult cattle, the efficacy of the rough Brucella abortus strain RB51 vaccine was tested in heifers. Thirty-three females of approximately 24 months of age were divided in two groups: one group (n = 20) received the RB51 vaccine and the other group (n = 13) were used as non-vaccinated control. Animals in the vaccinated group were split in two sub-groups. One sub-group (n = 12) was vaccinated subcutaneously with 1.5 × 10 10 colony forming units (CFU) of RB51 at Day 0 of the experiment and the other sub-group (n = 8) was vaccinated subcutaneously with 1.6 × 10 10 CFU of RB51 at 60 days of gestation (Day 260 of the experiment). All cattle were challenged between 6 and 7 months of pregnancy with 3 × 10 8 CFU of the virulent strain 2308 of B. abortus by the conjunctival route. Vaccination with RB51 vaccine did not result in the production of any antibodies against the O-side chain of lipopolysaccharide (LPS), as measured by conventional serological tests (rose bengal plate agglutination test (RBPAT), standard tube agglutination test (STAT), and 2-mercaptoethanol test (2ME)). A total of 25% cumulative incidence of abortions was found in the vaccinated group, whereas in the control group the cumulative incidence was 62%. B. abortus RB51 was not isolated from any sample, and no abortions were produced by RB51 vaccination of females at 60 days of pregnancy. The results indicate that vaccination with RB51 prevented 59.4% of abortions, 58.6% of cow infections, and 61.0% of fetal infections. The relative risk (RR) revealed that non-vaccinated animals have 2.462 (95% CI 1.029-5.889) times higher risk of aborting than RB51-vaccinated animals.
PROTEOMICS, 2012
Brucella abortus is a Gram-negative intracellular bacterium that causes infectious abortion in food-producing animals and chronic infection in humans. This study aimed to characterize a B. abortus S19 antigen preparation obtained by Triton X-114 (TX-114) extraction through immunoproteomics to differentiate infected from vaccinated cattle. Three groups of bovine sera were studied: GI, 30 naturally infected cows; GII, 30 S19-vaccinated heifers; and GIII, 30 nonvaccinated seronegative cows. One-dimensional (1D) and two-dimensional electrophoretic profiles of TX-114 hydrophilic phase antigen revealed a broad spectrum of polypeptides (10-79 kDa). 1D immunoblot showed widespread seroreactivity profile in GI compared with restricted profile in GII. Three antigenic components (10, 12, 17 kDa) were recognized exclusively by GI sera, representing potential markers of infection and excluding vaccinal response. The proteomic characterization revealed 56 protein spots, 27 of which were antigenic spots showing differential seroreactivity profile between GI and GII, especially polypeptides <20 kDa that were recognized exclusively by GI. MS/MS analysis identified five B. abortus S19 proteins (Invasion protein B, Sod, Dps, Ndk, and Bfr), which were related with antigenicity in naturally infected cattle. In conclusion, immunoproteomics of this new antigen preparation enabled the characterization of proteins that could be used as tools to develop sensitive and specific immunoassays for serodiagnosis of bovine brucellosis, with emphasis on differentiation between S19 vaccinated and infected cattle.
New Brucella abortus S19 Mutant to Improve Distinction Between Infected and Vaccinated Animals
Iranian Journal of Biotechnology, 2019
Background: Using Brucella abortus Strain 19 (S19) to control bovine brucellosis is restricted due to induce antibodies to the O-side chain of the smooth lipopolysaccharide (LPS) which may be difficult to differentiate vaccinated and infected animals. Furthermore, it is virulent for humans and can induce abortion to cattle. Objectives: The aim of this study was to employ gene knockout B. abortus S19 for the first time to eliminate diagnostic defects and obtain the attenuated mutant strain. Material and Methods: The wbkA gene, which is one of the LPS O-chain coding genes, was knocked out in vaccinal Brucella abortus S19. The proliferative response and immunoglobulin M production were analyzed in wbkA deletion strain-infected BALB/c mice. Results: The loss of wbkA gene function resulted in induction of the splenocyte proliferative response in mice infected by the mutant S19 strain compare to those induced by parental S19 and RB51 strains. Moreover, wbkA mutant did not induce any IgM antibody response using the enzyme-linked immunosorbent assay. Conclusions: As a result, the new mutant S19 strain had deficiency in its LPS O-chain structure, besides cannot induce IgM response then, reduce mistakes to discriminate between vaccinated and infected animal, and also can be considered as a new vaccine candidate.
Research in Veterinary Science, 2002
The Brucella melitensis mutant BM25, which lacks the major 25 kDa outer membrane protein Omp25, has previously been found to be attenuated in the murine brucellosis model. In the present study, the capacity of the Áomp25 mutant to colonise and cause abortions in the caprine host was evaluated. The vaccine potential of BM25 was also investigated in goats. Inoculation of nine pregnant goats in late gestation with the B. melitensis mutant resulted in 0/9 abortions, while the virulent parental strain, B. melitensis 16M, induced 6/6 dams to abort (P , 0Á001, n 6). BM25 also colonised fewer adults (P , 0Á05, n 6) and kids (P , 0Á01, n 6) than strain 16M. The Áomp25 mutant was found capable of transient in vivo colonisation of non-pregnant goats for two weeks post-infection. Owing to the ability of BM25 to colonise both non-pregnant and pregnant adults without inducing abortions, a vaccine efficacy study was performed. Vaccination of goats prior to breeding with either BM25 or the current caprine vaccine B. melitensis strain Rev. 1 resulted in 100 per cent protection against abortion following challenge in late gestation with virulent strain 16M (P , 0Á05, n 7). However, unlike strain Rev. 1, BM25 does not appear to cause abortions in late gestation based on this study with a small number of animals. The B. melitensis Áomp25 mutant, BM25, may be a safe and efficacious alternative to strain Rev. 1 when dealing with goat herds of mixed age and pregnancy status. #
Pakistan Veterinary …, 2010
Protein profiling Western blot analysis Outer membrane proteins Brucella abortus RB51 S19 Buffaloes Outer membrane proteins (OMPs) of three strains of B. abortus i.e. S19, RB51 and a local field isolate of biotype 1 were isolated through disrupting cells to generate membranes by centrifugation and sodium lauryl sarcosinate solubilisation of inner membrane proteins. Distinct OMP profiles of each strain were seen on SDS-PAGE. SDS-PAGE analysis of S19 and field isolate revealed eight protein bands in each strain. The OMPs of S19 had molecular masses 89.0, 73.0, 53.7, 49.0, 38.0, 27.0, 22.3, and 17.7 kDa, while field isolate had OMPs of 151.3, 89.0, 75.8, 67.6, 37.0, 27.0, 24.0 and 19.0 kDa. B. abortus RB51 yielded 11 OMP bands ranging from 12.5 to 107.1 kDa, with 34.2, 15.8 and 12.5 kDa as additional OMPs. Western immunoblot analysis using antisera raised against all three strains in buffaloes indicated an almost similar pattern of immuno-reactive OMPs in S19 and field strain. Two OMPs of molecular weight 37-38 and 19 kDa were immuno-reactive in all strains in buffaloes. There is possibility of use of these OMPs in a recombinant vaccine for B. abortus. A distinct protein of molecular weight of 151.3 kDa was identified in field strain but not in both vaccine strains of B. abortus. Use of this OMP in a diagnostic assay may differentiate between vaccinated and infected animals.
Vaccines, 2021
Vaccination of cattle and buffaloes with Brucella abortus strain 19 has been the mainstay for control of bovine brucellosis. However, vaccination with S19 suffers major drawbacks in terms of its safety and interference with serodiagnosis of clinical infection. Brucella abortus S19∆per, a perosamine synthetase wbkB gene deletion mutant, overcomes the drawbacks of the S19 vaccine strain. The present study aimed to evaluate the potential of Brucella abortus S19Δper vaccine candidate in the natural host, buffaloes. Safety of S19∆per, for animals use, was assessed in guinea pigs. Protective efficacy of vaccine was assessed in buffaloes by immunizing with normal dose (4 × 1010 colony forming units (CFU)/animal) and reduced dose (2 × 109 CFU/animal) of S19Δper and challenged with virulent strain of B. abortus S544 on 300 days post immunization. Bacterial persistency of S19∆per was assessed in buffalo calves after 42 days of inoculation. Different serological, biochemical and pathological s...
Identification of immunotolerance in the progeny of cows infected with Brucella abortus
African Journal of Microbiology Research, 2012
The progeny of cows infected with Brucella abortus could acquire the bacterium during their fetal stage and generate immune tolerance. In order to identify them, a clinical assay was conducted with two groups of seronegative calves. In Group I, seven bovine females received a standard S19 dose, and in Group II, eight males served as control. All animals were sampled seven times by official serological tests every 45 days. Also, complete blood with anticoagulant was collected and tested by the polymerase chain reaction (PCR) 45 and 135 days after vaccination. Results were analyzed by the test of proportions. In Group I, all the animals had their maximum antibodies title at the first sampling, but from the fourth sampling, their titles decreased until they became undetectable for the screening test. All animals in Group II remained negatives. Animals from both groups recorded negative with PCR. Significant differences (P<0.05) between groups were observed for seroconversion in the first two samplings. It was concluded that none of the tested animals were immunotolerant and that PCR may not be an appropriate method to demonstrate immunotolerence in some individuals.