Detection of Abrin in Food Using Enzyme-Linked Immunosorbent Assay and Electrochemiluminescence Technologies

2008 ◽  
Vol 71 (9) ◽  
pp. 1868-1874 ◽  
Author(s):  
ERIC A. E. GARBER ◽  
JENNIFER L. WALKER ◽  
THOMAS W. O'BRIEN
Keyword(s):  
Monoclonal Antibodies ◽  
Immunosorbent Assay ◽  
Dairy Products ◽  
Polyclonal Antibodies ◽  
Cross Reactivity ◽  
Enzyme Linked Immunosorbent Assay ◽  
Ribosome Inactivating Protein ◽  
Limits Of Detection ◽  
Abrus Precatorius ◽  
A Priority

Abrin is a toxic ribosome-inactivating protein present in beans of Abrus precatorius, also known as rosary peas. The possibility that abrin could be used to adulterate food has made the development of assays for the detection of abrin a priority. Rabbit-derived polyclonal antibodies and mouse monoclonal antibodies were prepared against a mixture of abrin isozymes. The specificity and cross-reactivity of the antibodies were evaluated against a challenge library of 40 grains, nuts, legumes, and foods. An enzyme-linked immunosorbent assay (ELISA) and an electrochemiluminescence (ECL)–based assay were assembled and optimized. Polyclonal (capture) and polyclonal (detection) ELISAs, polyclonal and monoclonal ELISAs, and polyclonal and monoclonal ECL assays had limits of detection (LODs) of 0.1 to 0.5 ng/ml for abrin in buffer. The LOD for abrin dissolved into juices, dairy products, soda, chocolate drink, and condiments and analyzed with the ECL assay ranged from 0.1 to 0.5 ng/ml in the analytical sample. In contrast, the LODs for the ELISAs ranged from 0.5 to 10 ng/ml in the analytical sample.

scholarly journals Development of Murine Monoclonal Antibodies for the Immunohistochemical Diagnosis of Systemic Bovine Aspergillosis

1996 ◽  
Vol 8 (1) ◽  
pp. 68-75 ◽  
Author(s):  
H. E. Jensen ◽  
B. Aalbaek ◽  
P. Lind ◽  
H. V. Krogh ◽  
P. L. Frandsen
Keyword(s):  
Monoclonal Antibodies ◽  
Polyclonal Antibodies ◽  
Fungal Species ◽  
Cross Reactivity ◽  
Water Soluble ◽  
Enzyme Linked Immunosorbent Assay ◽  
Immunohistochemical Techniques ◽  
Immunohistochemical Diagnosis ◽  
Murine Monoclonal Antibodies

Murine monoclonal antibodies (MAbs) against water-soluble somatic antigens (WSSA) and the wall fraction (WF) from Aspergillus fumigatus were produced by fusion of splenocytes from immunized BALB/c mice with mouse myeloma X63-Ag 8.653 cells. The supernatants of in vitro cultured hybridomas were initially screened for reactivity with the WSSA and the WF from A. fumigatus and WSSA of other fungi in an enzyme-linked immunosorbent assay (ELISA). Supernatants reacting only with A. fumigatus antigens were subsequently screened for homologous and heterologous reactivity with immunohistochemical techniques using formalin-fixed, paraffin-embedded tissues from experimentally infected mice. Because of a high immunohistochemical reactivity with homologous fungi, 4 MAbs raised against A. fumigatus WSSA and WF were selected for a further evaluation of cross-reactivity (diagnostic specificity) in immunohistochemical and immunoblotting assays. In immunohistochemical assays, all MAbs raised against WSSA cross-reacted heavily with a number of other fungal species. All 4 MAbs (MAb-WF-AF-1-4) raised against the WF reacted strongly with hyphae of Aspergillus spp.; hyphae of Scedosporium apiospermum were also strongly labeled by MAb-WF-AF-3 and-4. The 2 specifically reacting MAbs (MAb-WF-AF-1 and-2) were of the IgM biotype and were precipitating, and in immunoblotting experiments both bound to a 106-kD antigen of the WF, whereas they did not bind to WSSA of A. fumigatus. One of the 2 aspergillosis-specific MAbs (MAb-WF-AF-1) was used to screen 145 mycotic lesions of cattle. The diagnoses on bovine lesions obtained by MAb-WF-AF-1 were compared with results based on reactivity with heterologously absorbed polyclonal antibodies and, for some lesions, to culture results. In the vast majority of lesions ( n = 133), the MAb-WF-AF-1 and the polyclonal anti-Aspergillus antibodies reacted in a similar pattern, i.e., positively in 41 aspergillosis lesions and negatively in 92 zygomycotic lesions. Hyphae in 3 of 12 lesions that were not stained by the polyclonal antibodies reacted with the specific MAb-WF-AF-1; i.e., aspergillosis was diagnosed. The characteristics of the 2 MAbs (MAb-WF-AF-1 and-2) raised against the WF of A. fumigatus in ELISA and immunoblotting and immunohistochemical assays justify their application for the in situ diagnosis of systemic aspergillosis of cattle.

scholarly journals Development of an Enzyme-Linked Immunosorbent Assay for Serotyping Ureaplasma urealyticum Strains Using Monoclonal Antibodies

2001 ◽  
Vol 8 (1) ◽  
pp. 52-57 ◽  
Author(s):  
Fedoua Echahidi ◽  
Gaëtan Muyldermans ◽  
Sabine Lauwers ◽  
Anne Naessens
Keyword(s):  
Monoclonal Antibodies ◽  
Immunosorbent Assay ◽  
Ureaplasma Urealyticum ◽  
Polyclonal Antibodies ◽  
Enzyme Linked Immunosorbent Assay ◽  
Elisa Method ◽  
Cross Reactions ◽  
Antigenic Preparation ◽  
Negative Controls ◽  
Reference Strains

ABSTRACT Ureaplasma urealyticum comprises 14 serotypes. The existing serotyping methods all use polyclonal antibodies. These methods are time-consuming and labor-intensive, and they cannot always be performed on primary isolates; in addition, the results are difficult to interpret. We developed a new enzyme-linked immunosorbent assay (ELISA) method using serotype-specific monoclonal antibodies (MAbs) to enable the serotyping of U. urealyticum isolates from primary broth cultures. Each of the 14 serotype reference strains was tested against 14 selected MAbs. Homologous reactions were very strong, while heterologous reactions were negligible. Three cross-reactions were observed: MAb 5 cross-reacted with serotype 2, MAb 14 cross-reacted with serotype 3, and MAb 8 cross-reacted with serotype 13. Despite the cross-reactions observed, all the serotype reference strains ofU. urealyticum could be identified and differentiated using a combination of MAbs. Reproducibility was analyzed with a fractionated antigenic preparation and with several freshly prepared antigens of the same strain. No significant interrun variation was found with the fractionated antigen, but significant variations in optical density (OD) values were found when freshly prepared antigens were tested. However, the variation in OD values did not influence the overall interpretation of the ELISA: reactions with homologous MAbs were always prominent compared to those of the negative controls. This newly developed ELISA using MAbs seems promising for serotyping of U. urealyticum clinical isolates.

scholarly journals Production of Monoclonal Antibodies Specific for the i and 1,2 Flagellar Antigens of Salmonella typhimurium and Characterization of Their Respective Epitopes

1998 ◽  
Vol 64 (12) ◽  
pp. 5033-5038 ◽  
Author(s):  
N. de Vries ◽  
K. A. Zwaagstra ◽  
J. H. J. Huis in’t Veld ◽  
F. van Knapen ◽  
F. G. van Zijderveld ◽  
...  
Keyword(s):  
Amino Acids ◽  
Monoclonal Antibodies ◽  
Salmonella Typhimurium ◽  
Immunosorbent Assay ◽  
Specific Antibody ◽  
Polyclonal Antibodies ◽  
Enzyme Linked Immunosorbent Assay ◽  
Specific Antibodies ◽  
Minimal Area

ABSTRACT Salmonella typhimurium expresses two antigenically distinct flagellins, each containing a different H antigen (i and 1,2), the combination of which is highly specific for this serotype. In this study, overlapping recombinant flagellin fragments were constructed from the fliC(H:i) and fljB (H:1,2) flagellin genes, and the expression products were tested for binding to H antigen-specific monoclonal and polyclonal antibodies. A minimal area, 86 amino acids for H:i and 102 amino acids for H:1,2, located in the central variable domain of each flagellin was required for the binding of serotype-specific antibodies, providing further evidence for the presence of a discontinuous H epitope. Two peptides comprising these areas were shown to be highly suitable for application as antigens in an enzyme-linked immunosorbent assay detecting S. typhimurium-specific antibody.

Enzyme-Linked Immunosorbent Assay Detection of Melamine in Infant Formula and Wheat Food Products

2010 ◽  
Vol 73 (4) ◽  
pp. 701-707 ◽  
Author(s):  
ERIC A. E. GARBER ◽  
VICKERY A. BREWER
Keyword(s):  
Sample Preparation ◽  
Infant Formula ◽  
Immunosorbent Assay ◽  
Cyanuric Acid ◽  
Food Products ◽  
Cross Reactivity ◽  
Enzyme Linked Immunosorbent Assay ◽  
Limits Of Detection ◽  
Wheat Products ◽  
Assay Detection

The adulteration of food products with melamine to inflate the nitrogen content necessitates the establishment of analytical methods that can distinguish between proteinaceous ingredients and such adulterants. The specificity and ability to detect melamine by two commercial enzyme-linked immunosorbent assay (ELISA) kits were evaluated along with three protocols for sample preparation. Both ELISAs displayed cross-reactivity with ammeline, but neither was able to detect ammelide or cyanuric acid, indicating either a requirement for the 4,6-diamino-1,3,5-triazine structure or inability to bind 1,3,5-triazine-4,6-diones. The limits of detection for melamine in powder infant formula ranged from 0.2 to 3 μg/g depending on the ELISA kit and the method used to prepare the sample. The limits of detection for melamine in liquid infant formula and wheat products were <1 μg/ml and <2.5 μg/g, respectively. The ELISA kits provide an effective alternative for the analysis of samples suspected of containing melamine without relying on extensive sample preparation or expensive instrumentation.

Sensitive Measurement of Thrombopoietin by a Monoclonal Antibody Based Sandwich Enzyme-linked Immunosorbent Assay

1997 ◽  
Vol 78 (04) ◽  
pp. 1262-1267 ◽  
Author(s):  
Claudia C Folman ◽  
Albert E G K von dem Borne ◽  
Irma H J A M Rensink ◽  
Winald Gerritsen ◽  
C Ellen van der Schoot ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Monoclonal Antibodies ◽  
Immunosorbent Assay ◽  
Platelet Transfusion ◽  
Large Scale ◽  
Limit Of Detection ◽  
Cross Reactivity ◽  
Enzyme Linked Immunosorbent Assay ◽  
Reliable Tool

SummaryIn this report a sensitive enzyme-linked immunosorbent assay (ELISA) for the measurement of plasma thrombopoietin (Tpo) is described that is solely based on monoclonal antibodies (MoAbs).The assay has an intra and inter-assay variance of 5-7% and 7-13%, respectively. Native and recombinant human Tpo (rhTpo) were recognized equally well, no cross reactivity with other cytokines was found and rhTpo added to plasma and serum was completely recovered. With the ELISA, Tpo concentrations in EDTA-anticoagulated plasma of all controls (n = 193) could be determined, since the limit of detection (2 ± 0.8 A.U./ml, mean ± sd) was lower than the concentration found in controls (11 ± 8 A.U./ml, mean ± sd; 2.5th-97.5th percentile: 4-32 A.U./ml). Tpo levels in serum were on average 3.4 times higher than in plasma.We showed in vivo that Tpo is bound by platelets, as in thrombocytopenic patients (n = 5) a platelet transfusion immediately led to a drop in plasma Tpo level, whereas in patients receiving chemotherapy the induced thrombocytopenia was followed by a rise in plasma Tpo levels.In summary, these results indicate that this ELISA is a reliable tool for Tpo measurements and is applicable for large scale studies.

scholarly journals Rapid Detection of H5N1 Subtype Influenza Viruses by Antigen Capture Enzyme-Linked Immunosorbent Assay Using H5- and N1-Specific Monoclonal Antibodies

2009 ◽  
Vol 16 (5) ◽  
pp. 726-732 ◽  
Author(s):  
Hui-Ting Ho ◽  
Hong-Liang Qian ◽  
Fang He ◽  
Tao Meng ◽  
Milene Szyporta ◽  
...  
Keyword(s):  
Monoclonal Antibodies ◽  
Immunosorbent Assay ◽  
Rapid Detection ◽  
Conformational Epitope ◽  
Cross Reactivity ◽  
Influenza Viruses ◽  
Enzyme Linked Immunosorbent Assay ◽  
Influenza B ◽  
H5n1 Subtype ◽  
Antigen Capture

ABSTRACT Highly pathogenic avian influenza (HPAI) virus of the H5N1 subtype has caused devastating damage to poultry flocks and sporadic human H5N1 infections. There is concern that this virus subtype may gain transmissibility and become pandemic. Rapid diagnosis and surveillance for H5N1 subtype viruses are critical for the control of H5N1 infection. In this study, we report a robust antigen-capture enzyme-linked immunosorbent assay (AC-ELISA) based on H5- and N1-specific monoclonal antibodies (MAbs) for the rapid detection of H5N1 subtype viruses. The H5 hemagglutinin (HA)-specific MAb (2D9) targets a conformational epitope which recognized multiple clades of H5N1 viruses, including clades 0, 1, 2.1, 2.2, 2.3, 4, 7, and 8. The N1 neuraminidase (NA)-specific MAb (8H12) recognized a linear epitope comprising the sequence AELPF. This epitope was 99% conserved in the NA of 708 analyzed H5N1 viruses, while the epitope was absent in NAs of subtypes N2 through N9. The specificity of the AC-ELISA was examined by using 41 H5N1 HPAI strains from multiple clades, 36 non-H5N1 viruses, and 4 influenza B viruses. No cross-reactivity was observed for any of the non-H5N1 viruses tested. The estimated detection limit was 1 to 2 HA titers. It is concluded that this H5N1 AC-ELISA can simultaneously detect H5 and N1 subtype antigens, eliminating the need for secondary testing for the NA subtype. Implementation of this assay in ELISA-like formats suitable for field use, such as dot ELISA, immunofiltration, or electrochemical biosensor technologies, would provide dual on-site detection of H5 and N1 in clinical or environmental specimens.

scholarly journals Sandwich Enzyme-Linked Immunosorbent Assay for Detecting Sesame Seed in Foods

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Stef J. Koppelman ◽  
Gülsen Söylemez ◽  
Lynn Niemann ◽  
Ferdelie E. Gaskin ◽  
Joseph L. Baumert ◽  
...  
Keyword(s):  
Immunosorbent Assay ◽  
Polyclonal Antibodies ◽  
Peanut Butter ◽  
Seed Proteins ◽  
Sesame Seed ◽  
Cross Reactivity ◽  
Enzyme Linked Immunosorbent Assay ◽  
Food Ingredient ◽  
Limit Of Quantification ◽  
Food Ingredients

Small amounts of sesame can trigger allergic reactions in sesame-allergic patients. Because sesame is a widely used food ingredient, analytical methods are needed to support quality control and food safety programs in the food industry. In this study, polyclonal antibodies against sesame seed proteins were raised, and an enzyme-linked immunosorbent assay (ELISA) was developed for the detection and quantification of sesame seed residue in food. A comparison was made between this ELISA and other assays, particularly focusing on recovery of sesame seed residue from different food matrices. The developed ELISA is sensitive with a lower limit of quantification of 0.5 ppm and shows essentially no cross-reactivity with other foods or food ingredients (92 tested). The ELISA has a good recovery for analyzing sesame-based tahini in peanut butter, outperforming one other test. In a baked bread matrix, the ELISA has a low recovery, while two other assays perform better. We conclude that a sensitive and specific ELISA can be constructed based on polyclonal antibodies, which is suitable for detection of small amounts of sesame seed relevant for highly allergic patients. Furthermore, we conclude that different food products may require different assays to ensure adequate quantification of sesame.

Lactate Dehydrogenase as Safe Endpoint Cooking Indicator in Poultry Breast Rolls: Development of Monoclonal Antibodies and Application to Sandwich Enzyme-Linked Immunosorbent Assay (ELISA)

1993 ◽  
Vol 56 (2) ◽  
pp. 120-124 ◽  
Author(s):  
MOHAMED M. ABOUZIED ◽  
CHENG HSING WANG ◽  
JAMES J. PESTKA ◽  
DENISE M. SMITH
Keyword(s):  
Monoclonal Antibodies ◽  
Lactate Dehydrogenase ◽  
Immunosorbent Assay ◽  
Polyclonal Antibodies ◽  
Sandwich Elisa ◽  
Enzyme Linked Immunosorbent Assay ◽  
Department Of Agriculture ◽  
Poultry Products ◽  
Chicken Muscle ◽  
Assay Detection

A sandwich enzyme-linked immunosorbent assay (ELISA) was developed to detect lactate dehydrogenase (LDH) as a marker protein for verifying endpoint cooking of uncured poultry products. Monoclonal antibodies were prepared against chicken muscle LDH and used with rabbit polyclonal antibodies developed against turkey or chicken muscle LDH for capture and detection in the assay, respectively. Minimum assay detection limits for turkey and chicken muscle LDH were 1 ng/ml. Turkey and chicken muscle LDH, but not LDH from other species cross reacted in the ELISA. The ELISA was further verified using extracts of turkey breast rolls processed to internal temperatures between 68.3 and 72.1°C. The LDH content of extracts diluted 3- to 6-fold was below 15 ng/ml for turkey rolls processed to 70.9 and 72.1°C. At a 6-fold dilution, LDH content of extracts from rolls processed to 69.7°C was approximately 10 times greater than those processed to 70.9°C. A survey of market precooked poultry products indicated assay validity with precooked turkey roast, but not turkey hams with maximum internal temperature requirements of 68.3°C. Results suggested the sandwich ELISA should be applicable for determining whether turkey breast rolls are processed to the required U.S. Department of Agriculture endpoint temperature of 71.1°C.

A Sandwich Enzyme-Linked Immunosorbent Assay for the Detection of Almonds in Foods†

2000 ◽  
Vol 63 (2) ◽  
pp. 252-257 ◽  
Author(s):  
JASON J. HLYWKA ◽  
SUSAN L. HEFLE ◽  
STEVE L. TAYLOR
Keyword(s):  
Immunosorbent Assay ◽  
Polyclonal Antibodies ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecylsulfate ◽  
Food Samples ◽  
Cross Reactivity ◽  
Enzyme Linked Immunosorbent Assay ◽  
Sesame Seeds ◽  
Quality Control Tool ◽  
Sandwich Type

An enzyme-linked immunosorbent assay was developed to detect almonds as potential allergenic contaminants in food. Polyclonal antibodies directed against roasted almonds were partially purified from immunized sheep and rabbits and used as capture and secondary antibodies, respectively, in a sandwich-type, 96-well plate format. Food samples and almond-spiked samples were extracted 1:10 in phosphate-buffered saline at 60°C for 2 h, centrifuged, and applied to wells coated with sheep anti-almond antibody. After incubation, washing, and the addition of rabbit anti-almond antibody, the amount of almond present was detected with the subsequent addition of goat anti-rabbit immunoglobulin G–alkaline phosphatase conjugate and p-nitrophenyl phosphate substrate. Plate absorbances were read at 410 nm, and standard curves were developed in all matrices to quantify unknowns. Antibodies developed were specific for almond; however, some cross-reactivity was observed with extracts of some tree nuts and sesame seeds. Sodium dodecylsulfate–polyacrylamide gel electrophoresis and Western immunoblotting indicated that sheep anti-almond antibody recognized proteins extracted from black walnuts, Brazil nuts, cashews, hazelnuts, macadamia nuts, pistachios, and sesame seeds in addition to those from almond. The assay was optimized to detect less than 1 ppm of almond and was used successfully to determine almond residues in cereal and chocolate without cross-reacting interferences. A retail survey of 20 brands of cereal demonstrated that the assay produced statistically consistent results. This assay provides a useful quality control tool for the food industry for the protection of consumers allergic to almonds.

Immunohistochemical Diagnosis of Systemic Bovine Zygomycosis by Murine Monoclonal Antibodies

1996 ◽  
Vol 33 (2) ◽  
pp. 176-183 ◽  
Author(s):  
H. E. Jensen ◽  
B. Aalbæk ◽  
P. Lind ◽  
H. V. Krogh
Keyword(s):  
Monoclonal Antibodies ◽  
Lymph Nodes ◽  
Rhizopus Oryzae ◽  
Polyclonal Antibodies ◽  
Cross Reactivity ◽  
Water Soluble ◽  
Enzyme Linked Immunosorbent Assay ◽  
The Family ◽  
Murine Monoclonal Antibodies

Murine monoclonal antibodies (Mabs) against water-soluble somatic antigens (WSSA) and the wall fraction (WF) from Rhizopus arrhizus (Rhizopus oryzae) were produced in vitro by fusion of splenocytes from immunized BALB/c mice with mouse myeloma X63-Ag 8.653 cells. Supernatants reacting only with homologous antigens in an enzyme-linked immunosorbent assay were subsequently screened for reactivity with homologous fungi in immunohistochemical techniques. All four Mabs raised against the WF of A. arrhizus failed to react on tissues. However, four of the Mabs raised against the WSSA of R. arrhizus (Mab-WSSA-RA-1 through Mab-WSSA-RA-4) revealed a high homologous reactivity on tissues and the cross-reactivity of these were subsequently evaluated on tissues containing other members of the family Mucoraceae and other unrelated fungi. On tissues and on immunoblots all four Mabs reacted identically and specifically with members of the family Mucoraceae, i.e., Absidia corymbifera, R. arrhizus, and Rhizomucor pusillus. The Mabs were all isotyped as IgM antibodies, were nonprecipitating, and reacted with homologous antigens with molecular masses from 14 to 110 kDa. With WSSA from A. corymbifera and R. pusillus the four Mabs were bound to antigens from 14 to 52 kDa and from 20 to 28 kDa, respectively. The diagnosis of 145 bovine lesions obtained by one of the specific Mabs (Mab-WSSA-RA-1) were compared to results obtained by heterologously absorbed polyclonal antibodies. In most lesions ( n = 140 [∼ 97%]) the Mab and the polyclonal antibodies reacted in a similar pattern, i.e., positively for zygomycosis in 89 lesions, negatively in 41 aspergillosis lesions, and negatively in 10 undiagnosed lesions. Hyphae within two of four lesions in lymph nodes, which were not stained by the polyclonal antibodies, reacted with the specific Mab. However, in another three lesions of lymph nodes stained by the polyclonal antibodies no reactivity was seen with the Mab-WSSA-RA-1. The immunoreactivity of the Mabs (Mab-WSSA-RA-1 through Mab-WSSA-RA-4) raised against WSSA of R. arrhizus justify their application for the in situ diagnosis of systemic bovine zygomycosis.

Sign in / Sign up

Export Citation Format

Share Document