The effects of IgG2 and of antigen concentration on prozoning in the complement fixation test for bovine brucellosis

McNaught, D. J.; Chappel, R.J.; Allan, G. S.; Bourke, J. A.; Rogerson, B. A.

doi:10.1016/s0034-5288(18)33285-5

Cited by 18 publications

(3 citation statements)

References 4 publications

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“…It is noteworthy, however, that IgG2 antibodies were the more efficient blockers ( Fig. 9) and that bovine IgG2 antibodies have been associated with prozone phenomena in B. abortus-specific agglutination tests (11) and complement fixation tests (39).…”

Section: Discussionmentioning

confidence: 90%

Killing of Brucella abortus by bovine serum

et al. 1988

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Studies of the serum bactericidal system in bovine brucellosis were undertaken to investigate the role of the humoral immune response in protection of cattle against the facultative intracellular parasite Brucella abortus. Fresh sera from normal control cattle, infected cattle, and cattle immunized with B. abortus cell envelopes were collected before treatment and during the course of immunization or infection. Normal fresh bovine serum or fresh agammaglobulinemic serum from colostrum-deprived calves was effective in killing smooth virulent B. abortus 2308, but rough strains RB51 (a rough mutant of strain 2308) and 45/20 were much more senitive to serum. The difference in susceptibility to serum was shown to be correlated with differences in lipopolysaccharide chemotype, with the more resistant strain 2308 having 0 polysaccharide and the more susceptible strains 45/20 and RB51 lacking 0 side chains. By treatment of fresh serum with MgCl2 and EGTA [ethylene glycol-bis(IO-aminoethyl ether)-N,N,N',N'-tetraacetic acid] killing was shown to occur via the classical pathway of complement activation. When antibody to B. abortus was present, killing of strain RB51 increased but killing of smooth strain 2308 decreased. The earliest antibody response in serum from infected animals did not interfere with killing. When affinity-purified bovine immunoglobulins specific for B. abortus smooth lipopolysaccharide were added to fresh normal bovine serum, immunoglobulin Gl (IgGl) and IgG2 isotypes blocked killing but IgM and IgA isotypes did not. Thus, it appears that serum from previously unexposed animals or animals early during infection can kill smooth B. abortus, an appropriate defense mechanism before the organism becomes intracellular. At later stages of infection, blocking antibodies predominate.

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Section: Discussionmentioning

confidence: 90%

Killing of Brucella abortus by bovine serum

et al. 1988

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“…Nevertheless, when the sensitivity and specificity of the available serological tests are considered, there is general agreement that, although the complement fixation test (CFT) is superior to other tests for the detection of this disease (2, 12), it does have limitations. First, the CFT often shows anticomplementary reactions as well as prozones where immunoglobulin G2 (IgG2) antibodies to B. abortus block IgG1 and IgM antibodies (11). Second, some infected cattle may show aberrant serological reactions and are not detected (7,15).…”

mentioning

confidence: 99%

Comparison of enzyme-linked immunosorbent assay and complement fixation test for the detection of specific antibody in cattle vaccinated and challenged with Brucella abortus

Sutherland¹

1985

J Clin Microbiol

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An enzyme-linked immunosorbent assay (ELISA) and a complement fixation test (CFT) were applied to sera collected regularly from 60 cattle challenged with Brucella abortus strain 544. Of the 60 cattle, 48 were vaccinated with either B. abortus strain 19 or B. abortus strain 45/20 as calves or adults. The remaining 12 cattle were not vaccinated. Of the 27 sera from cattle found to be infected at slaughter, 9 showed aberrant reactions to the CFT in that a positive titer after challenge was delayed or transient. The performance of the ELISA in these nine cattle with aberrant reactions and the other cattle in the trial was as follows. After vaccination with strain 19 or strain 45/20, the number of weeks at which the ELISA was positive was significantly greater (P < 0.001) than that for the CFT. The strain 19 vaccine also induced positive responses to the CFT and the ELISA for a significantly longer period (P < 0.001) than did the strain 45/20 vaccine. For cattle with aberrant reactions, the number of weeks after challenge when the ELISA was positive was significantly greater (P < 0.001) than that for the CFT. For noninfected cattle, the average number of weeks after challenge when the CFT was negative (35 of 40) was higher than that for the ELISA (18 of 40).

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“…First, the CFT does not differentiate infected animals from animals recently vaccinated with Brucella abortus strain 19 (S19) or B. abortus strain 45/20 (S45/20) (5). Second, the test often shows anticomplementary reactions and prozones, the latter being the result of immunoglobulin G2-type antibodies to B. abortus blocking immunoglobulin Gl and immunoglobulin M antibodies (9). Third, CFT results are subject to great variations depending on minor differences in technique (1,10).…”

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confidence: 99%

Comparison of the complement fixation test and the indirect hemolysis test for cattle vaccinated and infected with Brucella abortus

Sutherland¹,

Cras²,

Evans³

1982

J Clin Microbiol

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The complement fixation test (CFT) and indirect hemolysis test (IHLT) were applied to sera collected from 60 cattle challenged with Brucella abortus 544. Of the 60 cattle, 48 were vaccinated with either B. abortus 19 or B. abortus 45/20 as calves or as adults. The remaining 12 cattle were not vaccinated. Of the 27 sera from cattle found to be infected, 9 showed aberrant reactions to the CFT. The advantages of the IHLT for these cattle were as follows. After challenge, the titers to the IHLT became positive earlier than or at the same time as the titers to the CFT, they persisted longer than the titers to the CFT, and they failed to show prozone reactions, which are a problem with the CFT. An additional advantage was that before challenge and after vaccination with strain 19, the titers to the IHLT rose later and declined earlier than the titers to the CFT. We concluded that the CFT used in conjunction with the IHLT improves the detection of infected cattle.

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The effects of IgG2 and of antigen concentration on prozoning in the complement fixation test for bovine brucellosis

Cited by 18 publications

References 4 publications

Killing of Brucella abortus by bovine serum

Killing of Brucella abortus by bovine serum

Comparison of enzyme-linked immunosorbent assay and complement fixation test for the detection of specific antibody in cattle vaccinated and challenged with Brucella abortus

Comparison of the complement fixation test and the indirect hemolysis test for cattle vaccinated and infected with Brucella abortus

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