Bovine brucellosis: Evaluation of field sera by a competitive and superimposable ELISA utilising a monoclonal antibody against Brucella abortus lipopolysaccharide

Chin, James; Daniels, Joanne; Bundesen, Peter

doi:10.1016/0165-2427(89)90092-5

Cited by 6 publications

(5 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In this type of assay, a binding reaction partner, antigen or antibody, is typically immobilized on the solid surfaces of microtiter plates consisting of multiple, small-volume-capacity wells made of plastic (e.g., polystyrene) . Such features of the analytical system not only allowed us an easy separation of the antigen−antibody binding complexes from unbound reagents by washing the surfaces but also allowed us to simultaneously process a number of samples for either qualitative or quantitative measurements. , For these reasons, since its introduction in 1971, it has been widely applied to various fields of analysis, such as medical diagnostics, food and environmental monitoring, and veterinary examination …”

mentioning

confidence: 99%

“…However, because of their huge molecular sizes, it is difficult to label them to immunoreagents without interferences in antigen−antibody bindings, , which rarely occurs with the small tracers. Enzymes are, moreover, sensitive to environmental variables, including inhibitory substances that may be inadvertently present in samples, and may alter their activities as catalysts. , Nevertheless, such unfavorable factors, although decidedly important, have not significantly restrained their utilization as tracers, and ELISA has been a routine, a standard laboratory method for analyses of complex organic substances for the last two decades. , …”

mentioning

confidence: 99%

“…3,4 For these reasons, since its introduction in 1971, it has been widely applied to various fields of analysis, such as medical diagnostics, 5 food and environmental monitoring, 6 and veterinary examination. 7 Compared to other tracers, such as radioisotopes and fluorophore, the enzymes used as signal generators in ELISA are huge, proteinacious molecules, which catalyze each specific substrate. 8 The catalytic action amplifies the signal, which, depending on its chemical properties, can be measured using a simple detector based on colorimetry, 9 luminometry, 10 and electrochemistry, 11,12 for example.…”

mentioning

confidence: 99%

“…Enzymes are, moreover, sensitive to environmental variables, including inhibitory substances that may be inadvert- ently present in samples, and may alter their activities as catalysts. 6,7 Nevertheless, such unfavorable factors, although decidedly important, have not significantly restrained their utilization as tracers, and ELISA has been a routine, a standard laboratory method for analyses of complex organic substances for the last two decades. 3,12 Despite its popularity, ELISA has rarely been applied to practical analyses conducted outside of the laboratory.…”

mentioning

confidence: 99%

See 3 more Smart Citations

Plastic ELISA-on-a-Chip Based on Sequential Cross-Flow Chromatography

et al. 2006

View full text Add to dashboard Cite

A plastic chip that can perform immunoassays using an enzyme as signal generator, i.e., ELISA-on-a-chip, was developed by incorporating an immunostrip into channels etched on the surfaces of the chip. To utilize an analytical concept of cross-flow chromatography, the chip consisted of two cross-flow channels in the horizontal and vertical directions. In the vertical channel, we placed a 2-mm-wide immunostrip for cardiac troponin I (cTnI), which was identical to a conventional rapid test kit except for the utilization of an enzyme, horseradish peroxidase (HRP), as tracer. An enzyme substrate supply channel and a horizontal flow absorption pad compartment were transversely arranged on each lateral side of the signal generation pad of the strip, respectively. Upon application of a sample containing cTnI, it migrated vertically through the membrane strip by capillary action, and antigen-antibody binding occurred. After 15 min, the horizontal flow was initiated by the addition of a chromogenic substrate solution for HRP into the supply channel and by partial superimposition of the horizontal flow absorption pad onto the signal generation pad. A color signal proportional to the analyte concentration was produced on this pad, measured after 5 min as optical densities using a digital camera-based detector, and quantified by integration of the densities under the peak after normalization. Its calibration curve indicated that the detection limit of the chip was approximately 0.1 ng/mL and its quantification limit was 0.25 ng/mL. In measuring blindly prepared samples, the chip performance correlated with that of a reference system, Beckman Coulter Access, within 2.5-fold discrepancy at the detection limit.

show abstract

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Plastic ELISA-on-a-Chip Based on Sequential Cross-Flow Chromatography

et al. 2006

View full text Add to dashboard Cite

show abstract

“…O aprimoramento dos testes sorológicos visando aprofundar o conhecimento da interferência da resposta vacinal sobre eles vem sendo o objetivo de um grande núme-ro de trabalhos científicos desenvolvidos em todo o mundo (Diaz et al 1979, Cherwonogrodzky & Nielsen 1988, Chin et al 1989, Nielsen et al 1989, Mathias et al 1994, Nielsen et al 1995, Nielsen et al 1996. Dos testes sorológicos convencionais, a reação de fixação de complemento geralmente apresenta maior capacidade de discriminação do que os testes de aglutinação (Nicoletti et al 1978).…”

Section: Introdução Introduçãounclassified

Evolução de títulos sorológicos, nas provas de soroaglutinação em placa, antígeno acidificado tamponado e fixação de complemento, em bezerras Nelore vacinadas aos 18 meses de idade com Brucella abortus amostra B 19

et al. 2001

View full text Add to dashboard Cite

One hundred and eight Nelore heifers (Bos indicus) about 18 months of age were vaccinated with a standard dosage (60-120 x 10 9 viable organisms) of Brucella abortus strain 19 vaccine, aiming at to study the persistence of serological antibody titres by the plate agglutination, rose Bengal and complement fixation tests. Serum samples were collected just before vaccination and after 45 days, 6, 12 and 18 months. Before the vaccination, all the heifers showed negative results by the three tests. After 45 days, all the heifers had titres higher than or equal to 1/100 by the plate agglutination test and all of them showed positive results by the rose Bengal plate test, while 2 animals had titre 1/2 and 106 animals had titres higher than or equal to 1/4 by the complement fixation test. One year after the vaccination, most of the heifers did not show significant serological antibody titres.Considering the risk to which animals in endemic areas and infected herds are subjected, and considering the clear reduction of the serological antibody titres shown by most of the vaccinated heifers, one may assume that, in case of Nelore heifers in endemic areas and that were not vaccinated between 3 and 8 months of age, it would be more reasonable to vaccinate them at 18 months of age than to expose them to a high risk of Brucella infection.INDEX TERMS: Bovine brucellosis, strain 19 vaccine, serological response.

show abstract