Monoclonal Antibody–Based Sandwich Enzyme-Linked Immunosorbent Assay for Sensitive Detection of Prohibited Ruminant Proteins in Feedstuffs

2004 ◽  
Vol 67 (3) ◽  
pp. 544-549 ◽  
Author(s):  
FUR-CHI CHEN ◽  
Y.-H. PEGGY HSIEH ◽  
ROGER C. BRIDGMAN

Regulations aimed to control the epidemic of bovine spongiform encephalopathy have banned the use of certain animal products, i.e., ruminant meat and bone meals, in ruminant animal feeds. A sensitive enzyme-linked immunosorbent assay has been developed to detect prohibited bovine and ovine muscles in feedstuffs. The assay utilizes a pair of monoclonal antibodies (MAbs) against skeletal troponin I (TnI). MAb 5G9, specific to bovine and ovine TnI, was used as the capture antibody and the biotin-conjugated MAb 2G3, reacting to all heterologous TnI, was used as the detection antibody. Quantitative procedures were applied to samples containing 5, 0.5, and 0.05% (wt/wt) of heat-treated (132°C/2 bar, 2 h) bovine and ovine meat meals in three different feeds, coexisting with porcine, chicken, or turkey meat meal. The presence of these nonprohibited species did not affect the detection of bovine and ovine meat meals in the feed samples (P > 0.05). Quantitative determinations of extractable bovine and ovine TnI, with a detection limit of 5.0 and 4.0 ng/ml, respectively, were achieved when the matching feed matrixes were used in the calibration curves. This new assay provides a rapid and reliable way to detect animal protein products containing a trace amount of bovine or ovine muscle tissue in feedstuffs.

1994 ◽  
Vol 57 (2) ◽  
pp. 104-107 ◽  
Author(s):  
ALLISON D. CRANDALL ◽  
KAREN WINKOWSKI ◽  
THOMAS J. MONTVILLE

The ability of Pediococcus pentosaceus to inhibit Clostridium botulinum toxigenesis in minimally heat-treated, vacuum-packaged sous vide-type beef with gravy was investigated. The bacteriocinogenic strain P. pentosaceus ATCC 43200 and the nonbacteriocinogenic strain P. pentosaceus 43NP1 were coinoculated with proteolytic and nonproteolytic C. botulinum types A and B spores into minimally processed meat with gravy. Toxin was present in samples inoculated with C. botulinum alone by day 31 at 4°C and by day 6 at 10°C. When coinoculated with C. botulinum, neither strain of Pediococcus was capable of significantly delaying the appearance of toxin. Although an enzyme-linked immunosorbent assay method for botulinal toxin was useful for screening toxin-positive samples, a high proportion of false negatives was revealed by confirmatory mouse bioassays. This research confirms that, if botulinal spores are present, sous vide beef does present a botulinal hazard, even when kept under adequate refrigeration.


2009 ◽  
Vol 637 (1-2) ◽  
pp. 273-278 ◽  
Author(s):  
Giampiero Scortichini ◽  
Loredana Annunziata ◽  
Valeria Di Girolamo ◽  
Roberta Buratti ◽  
Roberta Galarini

1991 ◽  
Vol 37 (9) ◽  
pp. 1645-1648 ◽  
Author(s):  
M Tozuka ◽  
Y Yoshida ◽  
J Tanigami ◽  
M Miyachi ◽  
T Katsuyama ◽  
...  

Abstract Measurement of apolipoprotein (apo) E-AII complex in human plasma is important in determining the role of apoE in lipoprotein metabolism. In this paper, we demonstrate a new and simple method to determine apoE-All complex by using an enzyme-linked immunosorbent assay. Anti-apoE IgG (goat) was used as a capture antibody, and captured apoE-All complexes were detected by an anti-apoAll (rabbit) horseradish peroxidase-conjugated anti-rabbit IgG (goat) system. With this method, apoE-All complex was specifically determined without the interference of apoAll and was not affected by apoE monomer less than 250 mg/L. The content of the complex in reference serum, a normolipidemic serum pooled from five subjects with phenotype E3/E3, was arbitrarily defined as 100%. The coefficients of variation were 3.5%-6.3% within assay and 8.8%-11.6% between assays.


2020 ◽  
Author(s):  
Pinpin Ji ◽  
Jiahong Zhu ◽  
Xiaoxuan Li ◽  
Wenqi Fan ◽  
Qianqian Liu ◽  
...  

Abstract Background: Traditional sandwich enzyme-linked immunosorbent assay (ELISA) using polyclonal and monoclonal antibodies as reagents presents several drawbacks, including limited amounts, difficulty in permanent storage, and required use of a secondary antibody. Nanobodies can be easily expressed with different systems and fused with several tags in their tertiary structure by recombinant technology, thus offering an effective detection method for diagnostic purposes. Recently, the fenobody (ferritin-fused nanobody) and RANbody (nanobody-fused reporter) have been designed and derived from the nanobody for developing the diagnostic immunoassays. However, there was no report about developing the sandwich ELISA using the fenobody and RANbody as pairing reagents.Results: A platform for developing a sandwich ELISA utilizing fenobody as the capture antibody and RANbody as the detection antibody was firstly designed in the study. Newcastle disease virus (NDV) was selected as the antigen, from which 13 NDV-specific nanobodies were screened from an immunized Bactrian camel. Then, 5 nanobodies were selected to produce fenobodies and RANbodies. The best pairing of fenobodies (NDV-fenobody-4, 800 ng/well) and RANbodies (NDV-RANbody-49, 1:10) was determined to develop the sandwich ELISA for detecting NDV. The detection limits of the assay were determined to be 22 of hemagglutination (HA) titers and 10 ng of purified NDV particles. Compared with two commercial assays, the developed assay shows higher sensitivity and specificity. Meanwhile, it exhibits 98.7% agreement with the HA test and can detect the reference NDV strains belonging to Class II but not Class I. Conclusions: In the presented study, the 13 anti-NDV nanobodies binding the NDV particles were first produced. Then, for the first time, the sandwich ELISA to detect the NDV in the different samples has been developed using the fenobody and RANbody as reagents derived from the nanobodies. Considering the rapidly increasing generation of nanobodies, the platform can reduce the cost of production for the sandwich ELISA and be universally used to develop assays for detecting other antigens.


Sign in / Sign up

Export Citation Format

Share Document