scholarly journals Establishment of a sandwich ELISA for bovine plasma PON-1 and its predictive capabilities for dairy cows with fatty liver

2021 ◽  
Vol 91 (5) ◽  
pp. 503-512
Author(s):  
Chang Zhao ◽  
◽  
Yunlong Bai ◽  
Dong Wang ◽  
Cheng Xia
Keyword(s):  
Monoclonal Antibody ◽  
Dairy Cows ◽  
Polyclonal Antibodies ◽  
Characteristic Curve ◽  
Sandwich Elisa ◽  
Paraoxonase 1 ◽  
Hybridoma Cells ◽  
Quantitative Detection ◽  
Bovine Plasma ◽  
Fatty Livers

The aim of this study to improve the clinical diagnosis of fatty livers (FL) in dairy cows by using the paraoxonase-1 (PON-1) enzyme as a detection index. Prokaryotic expression technology was used to generate recombinant bovine PON-1 protein. Mice were immunized with this protein to generate hybridoma cells, stably secreting anti-PON-1. Cells were injected into the peritoneal cavity of mice, and ascites were purified to generate bovine PON-1 monoclonal antibody. Rabbits were then immunized with this antigen, and a polyclonal antibody against bovine PON-1 was obtained. Using monoclonal and polyclonal antibodies, a double-antibody sandwich ELISA for plasma PON-1 was constructed. Plasma samples were collected from healthy (n = 13) and FL (n = 13) cows, and plasma PON-1 levels were detected using the PON-1 ELISA. Receiver operating characteristic curve (ROC) analysis was used to analyze correlations between PON-1 levels and FL. Results showed that the ideal working concentration of the monoclonal antibody was 0.8 mg/mL, and the quantitative detection limit was 90 ng/mL. Plasma PON-1 levels were significantly lower in FL cows, when compared with healthy animals. It is concluded that PON-1 ELISA predicts risk factors for dairy cows with FL. PON-1 levels in plasma can be used as an early warning indicator for FL and concentration of 61.87 nmol/L was identified as warning index.

Production of a monoclonal antibody specific for ovine immunoglobulin E and its application to monitor serum IgE responses to Haemonchus contortus infection

Parasitology ◽  
1997 ◽  
Vol 114 (4) ◽  
pp. 395-406 ◽  
Author(s):  
F. N. J. KOOYMAN ◽  
P. J. S. VAN KOOTEN ◽  
J. F. HUNTLEY ◽  
A. MacKELLAR ◽  
A. W. C. A. CORNELISSEN ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Haemonchus Contortus ◽  
Immunoglobulin E ◽  
Polyclonal Antibodies ◽  
Sandwich Elisa ◽  
Specific Ige ◽  
Cross Reactivity ◽  
Total Serum ◽  
Western Blots ◽  
Serum Ige

Part of the Cε3–Cε4 region of the ovine immunoglobulin E (IgE) gene (nucleotides 1111–1575) was amplified by PCR. The recombinant protein (recIgE1-2) was expressed in E. coli and both monoclonal and polyclonal antibodies were produced. These antibodies recognized recIgE1-2 and native IgE on Western blots and in ELISA. The polyclonal serum showed cross-reactivity with other sheep immunoglobulin classes. The monoclonal antibody was specific for ovine IgE and goat IgE. Infection of sheep with the abomasal nematode Haemonchus contortus resulted in elevated IgE levels in serum 2–4 weeks after infection, as measured by sandwich ELISA using the rabbit polyclonal as capture antibody and the monoclonal antibody against ovine IgE as second antibody. A negative correlation between worm counts and total serum IgE levels at the end of the experiment was found in repeatedly infected sheep. Significant increased levels of excretory–secretory antigens specific IgE levels were found after H. contortus infection. In contrast, no significant changes in 3rd-stage larvae (L3) antigen-specific IgE titre in sera could be detected after infection.

Immunofluorescence Assay Using Monoclonal and Polyclonal Antibodies for Detection of Staphylococcal Enterotoxins A in Milk

2019 ◽  
Vol 13 (1) ◽  
pp. 137-145 ◽  
Author(s):  
Tzonka Godjevargova ◽  
Zlatina Becheva ◽  
Yavor Ivanov ◽  
Andrey Tchorbanov
Keyword(s):  
Monoclonal Antibody ◽  
Magnetic Nanoparticles ◽  
Polyclonal Antibody ◽  
Polyclonal Antibodies ◽  
Food Poisoning ◽  
Staphylococcal Enterotoxin ◽  
Staphylococcal Enterotoxin A ◽  
Fluorescence Immunoassay ◽  
Magnetic Separator ◽  
Milk Samples

Objectives: Staphylococcus aureus is a Gram-positive microorganism. S. aureus can grow in various foods and cause food poisoning by secreting enterotoxins. The most common enterotoxins involved in food poisoning are staphylococcal enterotoxin A and staphylococcal enterotoxin B, but Staphylococcal Enterotoxin A (SEA) is predominant. The main types of food contaminated with SEs are meat and meat products, poultry and eggs, milk and dairy products. The aim of this study was to develop a rapid and sensitive fluorescence immunoassay for detection of staphylococcal enterotoxin A in milk. Methods: Monoclonal and polyclonal antibodies for SEA were produced and characterized. Competitive fluorescence immunoassay based on Magnetic Nanoparticles (MNPs) was performed and optimized. MNPs were used as a solid carrier of the antibodies. The first step of the assay was immunoreaction between the immobilized antibody onto MNPs and SEA in milk sample. Then the fluorescein-SEA conjugate was added to the sample. Thus, competitive immunoreaction between MNP-mAb/MNP-pAb with SEA and SEA-FITC was performed. These immuno-complexes were separated by a magnetic separator and the obtained supernatants were analyzed. The fluorescent signal from the excess of conjugated SEA was proportional to the SEA contained in the milk. The assay duration was only 30 min. Results: The fluorescence immunoassays performed with polyclonal antibody had linear ranges from 5 pg/mL to 100 ng/mL SEA in a buffer, and from 50 pg/mL to 50 ng/mL SEA in spiked milk samples. While the same assays performed with monoclonal antibody had linear ranges from 1 pg/mL to 20 ng/mL SEA in buffer, and from 10 pg/mL to 10 ng/mL SEA in spiked milk samples. The detection limits of the developed immunoassays performed in milk were: 48 pg/mL with polyclonal antibody and 9 pg/mL with monoclonal antibody. Conclusion: A rapid and sensitive fluorescence immunoassay based on magnetic nanoparticles with a polyclonal and monoclonal antibody for determination of staphylococcal enterotoxin A in milk was developed.

scholarly journals Plasma PCSK9 Concentrations Correlate with LDL and Total Cholesterol in Diabetic Patients and Are Decreased by Fenofibrate Treatment

2008 ◽  
Vol 54 (6) ◽  
pp. 1038-1045 ◽  
Author(s):  
Gilles Lambert ◽  
Nicolas Ancellin ◽  
Francesca Charlton ◽  
Daniel Comas ◽  
Julia Pilot ◽  
...  
Keyword(s):  
Ldl Cholesterol ◽  
Polyclonal Antibodies ◽  
Sandwich Elisa ◽  
Ldl Receptor ◽  
Hdl Cholesterol ◽  
Diabetic Patients ◽  
Plasma Triglycerides ◽  
Fenofibrate Treatment ◽  
Before And After ◽  
Fenofibrate Intervention

Abstract Background: Proprotein convertase subtilisin/kexin type 9 (PCSK9) promotes the degradation of the LDL receptor (LDLr) in hepatocytes, and its expression in mouse liver has been shown to decrease with fenofibrate treatment. Methods: We developed a sandwich ELISA using recombinant human PCSK9 protein and 2 affinity-purified polyclonal antibodies directed against human PCSK9. We measured circulating PCSK9 concentrations in 115 diabetic patients from the FIELD (Fenofibrate Intervention and Event Lowering in Diabetes) study before and after fenofibrate treatment. Results: We found that plasma PCSK9 concentrations correlate with total (r = 0.45, P = 0.006) and LDL (r = 0.54, P = 0.001) cholesterol but not with triglycerides or HDL cholesterol concentrations in that cohort. After 6 weeks of treatment with comicronized fenofibrate (200 mg/day), plasma PCSK9 concentrations decreased by 8.5% (P = 0.041 vs pretreatment). This decrease correlated with the efficacy of fenofibrate, as judged by a parallel reduction in plasma triglycerides (r = 0.31, P = 0.015) and LDL cholesterol concentrations (r = 0.27, P = 0.048). Conclusions: We conclude that this decrease in PCSK9 explains at least in part the LDL cholesterol–lowering effects of fenofibrate. Fenofibrate might be of interest to further reduce cardiovascular risk in patients already treated with a statin.

Lactate Dehydrogenase Monoclonal Antibody Sandwich ELISA To Determine Cooking Temperature of Ground Beef

1996 ◽  
Vol 44 (12) ◽  
pp. 4048-4051 ◽  
Author(s):  
A. Orta-Ramirez ◽  
C. H. Wang ◽  
M. M. Abouzied ◽  
G. J. Veeramuthu ◽  
J. F. Price ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Lactate Dehydrogenase ◽  
Sandwich Elisa ◽  
Ground Beef ◽  
Cooking Temperature

scholarly journals Detection of Mycoplasma agalactiae Antigen in Sheep and Goats by Monoclonal Antibody-Based Sandwich ELISA

2004 ◽  
Vol 73 (4) ◽  
pp. 461-464 ◽  
Author(s):  
D. Zendulková ◽  
H. J. Ball ◽  
A. Madanat ◽  
P. Lány ◽  
Z. Pospíšil
Keyword(s):  
Monoclonal Antibody ◽  
Sandwich Elisa ◽  
Mycoplasma Agalactiae ◽  
Sheep And Goats

Development of a monoclonal antibody against the left wing of ciguatoxin CTX1B: Thiol strategy and detection using a sandwich ELISA

Toxicon ◽  
2012 ◽  
Vol 60 (3) ◽  
pp. 348-357 ◽  
Author(s):  
Takeshi Tsumuraya ◽  
Katsutoshi Takeuchi ◽  
Shuji Yamashita ◽  
Ikuo Fujii ◽  
Masahiro Hirama
Keyword(s):  
Monoclonal Antibody ◽  
Sandwich Elisa ◽  
Left Wing

scholarly journals Functional study of a monoclonal antibody to IgE Fc receptor (Fc epsilon R2) of eosinophils, platelets, and macrophages.

1986 ◽  
Vol 164 (1) ◽  
pp. 72-89 ◽  
Author(s):  
M Capron ◽  
T Jouault ◽  
L Prin ◽  
M Joseph ◽  
J C Ameisen ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
B Lymphocyte ◽  
Specific Binding ◽  
Polyclonal Antibodies ◽  
Fc Receptor ◽  
The Other ◽  
Functional Study ◽  
Low Density ◽  
Fluorescence Staining ◽  
Ige Binding

An IgM mAb (BB10) was produced by immunization of mice with human eosinophils purified according to their abnormal low density ("hypodense" cells), and previously shown to exhibit increased IgE-dependent antiparasite cytotoxicity. This BB10 antibody, selected for positive fluorescence staining of hypodense blood or lung eosinophils and low or negative staining of normodense eosinophils or neutrophils, could strongly inhibit IgE-dependent cytotoxicity of human eosinophils and platelets. The specificity for the IgE Fc receptor was suggested by the high levels of inhibition of IgE rosettes formed by eosinophils after incubation with the purified IgM fraction of BB10, whereas other receptors (Fc gamma R, CR1) were not affected. On the other hand, BB10, able to inhibit rat eosinophil Fc epsilon R, did not react with the IgE Fc receptor on mast cells or basophils. A technique using radioiodinated BB10 allowed us to quantify the specific binding of BB10 to human eosinophils and platelets. Competition experiments revealed a crossinhibition between the binding of BB10 and IgE, suggesting the specificity of BB10 for the IgE binding site of eosinophil, platelet, and monocyte Fc epsilon R. Three proteins having extrapolated Mr of 32,000, 43,000-45,000, and 97,000 were found in the platelet extract eluted from a BB10 or from an IgE immunosorbent column. These findings confirm the similarities between IgE Fc receptors on human eosinophils, platelets, and macrophages, already observed with polyclonal antibodies directed against the B lymphocyte Fc epsilon receptor. They suggest, moreover, that the mAb BB10 can represent a good reagent for further investigations on the structure and the functions of this IgE Fc receptor (Fc epsilon R2).

scholarly journals Circumsporozoite proteins of malaria parasites contain a single immunodominant region with two or more identical epitopes.

1983 ◽  
Vol 157 (6) ◽  
pp. 1947-1957 ◽  
Author(s):  
F Zavala ◽  
A H Cochrane ◽  
E H Nardin ◽  
R S Nussenzweig ◽  
V Nussenzweig
Keyword(s):  
Monoclonal Antibody ◽  
Monoclonal Antibodies ◽  
Specific Binding ◽  
Polyclonal Antibodies ◽  
Binding Assays ◽  
Malaria Parasites ◽  
Immunodominant Region ◽  
Additional Finding ◽  
Single Region ◽  
Competition Binding

We have used panels of monoclonal antibodies to circumsporozoite (CS) proteins of Plasmodium falciparium, P. vivax, and P. knowlesi to determine the number of topographically independent epitopes of these antigens. The results of competition binding assays indicated that single regions of the CS molecules were recognized by the homologous monoclonal antibodies. Competition binding assays were also used to study the specificity of antibodies contained in the sera of humans and monkeys that had developed sterile immunity after immunization with irradiated, intact sporozoites. We found that single monoclonal antibodies inhibited 70-95% of the specific binding of the polyclonal antibodies to crude extracts of sporozoites. It appears, therefore, that CS proteins are among the most immunogenic constituents of sporozoites, and that a single region of these molecules contains most of the immunogenic activity. An additional finding was that the immunodominant region of CS molecules is multivalent with regard to the expression of a single epitope. This was demonstrated by the ability of monomers of CS proteins to bind simultaneously two or more molecules of the same monoclonal antibody.

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