scholarly journals Complement Fixation Test To Assess Humoral Immunity in Cattle and Sheep Vaccinated with Brucella abortusRB51

1999 ◽  
Vol 6 (6) ◽  
pp. 787-790 ◽  
Author(s):  
Rosanna Adone ◽  
Franco Ciuchini

ABSTRACT The live attenuated Brucella abortus strain RB51 is a rifampin-resistant, lipopolysaccharide (LPS) O-chain-deficient mutant of virulent B. abortus 2308. The reduced O-chain content in RB51 prevents this bacterium from inducing antibodies detectable by the conventional serologic tests for bovine brucellosis diagnosis that mainly identify antibodies to LPS. The absence of available serologic tests for RB51 also complicates the diagnosis of possible RB51 infections in humans exposed to this strain. The purpose of this study was to evaluate the suitability of a complement fixation (CF) test performed with the rough strain B. abortus RB51, previously deprived of anticomplementary activity, in detecting anti-B. abortus RB51 antibodies in cattle and sheep experimentally vaccinated with this strain. The results of this study showed that a CF test with RB51 as the antigen is able to specifically detect antibodies following RB51 vaccination in cattle and sheep. In addition, this method could be a useful tool for detecting B. abortus RB51 infection in humans.

2001 ◽  
Vol 8 (1) ◽  
pp. 119-122 ◽  
Author(s):  
Rosanna Adone ◽  
Franco Ciuchini

ABSTRACT The efficacy of Brucella abortus RB51 and hot saline extract (HSE) from Brucella ovis as antigens in complement fixation (CF) tests was comparatively evaluated in detecting immune responses of sheep vaccinated with B. abortus strain RB51. For this study, four 5-month-old sheep were vaccinated subcutaneously with 5 × 109 CFU of RB51, and two sheep received saline. Serum samples collected at different times after vaccination were tested for the presence of antibodies to RB51 by a CF test with RB51 as antigen, previously deprived of anticomplementary activity, and with HSE antigen, which already used as the official antigen to detectB. ovis-infected sheep. The results showed that vaccinated sheep developed antibodies which reacted weakly against HSE antigen and these antibodies were detectable for 30 days after vaccination. However, antibodies to RB51 could be detected for a longer period after vaccination by using homologous RB51 antigen in CF tests. In fact, high titers were still present at 110 days postvaccination with RB51 antigen. Sera from sheep naturally infected with B. ovisalso reacted to RB51 but gave lower titers than those detected by HSE antigen. As expected, all sera from RB51-vaccinated sheep remained negative when tested with standard S-type Brucella standard antigens.


1976 ◽  
Vol 77 (3) ◽  
pp. 369-376 ◽  
Author(s):  
R. J. Chappel ◽  
P. Williamson ◽  
D. J. McNaught ◽  
M. J. Dalling ◽  
G. S. Allan

SUMMARYA radioimmunoassay (RIA) has been developed to measure antibodies against Brucella abortus in bovine serum and can be used in the diagnosis of bovine brucellosis. The RIA measures the amount of specific antibody of the IgG1 and IgG2 subclasses but is insensitive to 1gM, a characteristic which may make it more suitable than the complement fixation test (OFT) or the serum agglutination test for distinguishing infected animals from those which have been vaccinated with Br. abortus strain 19. The RIA is not subject to prozoning or ambiguous reactions, both of which interfere with the interpretation of the CFT.


1976 ◽  
Vol 76 (2) ◽  
pp. 287-298 ◽  
Author(s):  
G. S. Allan ◽  
R. J. Chappel ◽  
P. Williamson ◽  
D. J. McNaught

SUMMARYBrucella-specific antibodies of different immunoglobulin classes were quantitatively evaluated with respect to their efficiency in serological tests for bovine brucellosis.IgM reacted more efficiently than IgG1and IgG2in both the Rose Bengal plate test and serum agglutination test. The complement fixation test was found to be slightly more sensitive to IgM than to IgG1and did not react to IgG2.IgM was, however, partly inactivated when heated at 60°C. in the presence of serum.


2006 ◽  
Vol 75 (2) ◽  
pp. 988-996 ◽  
Author(s):  
Rosanna Capparelli ◽  
Flora Alfano ◽  
Maria Grazia Amoroso ◽  
Giorgia Borriello ◽  
Domenico Fenizia ◽  
...  

ABSTRACT We tested 413 water buffalo cows (142 cases and 271 controls) for the presence of anti-Brucella abortus antibodies (by the skin test, the agglutination test, and the complement fixation test) and the Nramp1 genotype (by capillary electrophoresis). Four alleles (Nramp1A, -B, -C, and -D) were detected in the 3′ untranslated region of the Nramp1 gene. The BB genotype was represented among only controls, providing evidence that this genotype confers resistance to Brucella abortus. The monocytes from the BB (resistant) subjects displayed a higher basal level of Nramp1 mRNA and a lower number of viable intracellular bacteria than did the monocytes from AA (susceptible) subjects. The higher basal level of the antibacterial protein Nramp1 most probably provides the BB animals with the possibility of controlling bacteria immediately after their entry inside the cell.


1983 ◽  
Vol 90 (1) ◽  
pp. 67-70 ◽  
Author(s):  
R. J. Chappel ◽  
J. Hayes

SUMMARYSera were collected from female cattle in 118 commercial herds being subjected to a programme to eradicate brucellosis by test and slaughter, in an area in which vaccination of heifer calves with Brucella abortus strain 19 was compulsory. Of 4583 sera positive by the Rose Bengal plate test, the brucellosis radioimmunoassay was positive for 1524, the complement fixation test for 1363 and the indirect haemolysis test for 1141. These figures, and supporting evidence from the eradication programme, suggest that the radioimmunoassay may be a useful supplementary test in problem herds.


Author(s):  
U.W. Hesterberg ◽  
R. Bagnall ◽  
K. Perrett ◽  
B. Bosch ◽  
R. Horner ◽  
...  

A serological survey of Brucella abortus in cattle originating from communal grazing areas of Kwa Zulu Natal was carried out between March 2001 and December 2003. The survey was designed as a 2-stage survey, considering the diptank as the primary sampling unit. In total 46 025 animals from 446 diptanks of 33 magisterial districts were sampled and tested using the Rose Bengal test and Complement Fixation Test. The apparent prevalence at district level was adjusted for clustering, diagnostic test sensitivity and specificity, and mapped using ArcView version 3.3. The prevalence of brucellosis in communal grazing areas of Kwa-Zulu Natal was found to be 1.45 % (0.84-2.21 %) and varied from 0 to 15.6% between magisterial districts. In 19 of the 33 magisterial districts no serological reactors were observed. A large variation in prevalence was found within diptank areas. Brucellosis was found to be most prevalent in the northeastern area of the province. The findings of the survey are discussed.


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