scholarly journals Development of Aflatoxin B1-Lysine Adduct Monoclonal Antibody for Human Exposure Studies

2001 ◽  
Vol 67 (6) ◽  
pp. 2712-2717 ◽  
Author(s):  
Jia-Sheng Wang ◽  
Salahaddin Abubaker ◽  
Xia He ◽  
Guiju Sun ◽  
Paul T. Strickland ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Monoclonal Antibodies ◽  
High Risk ◽  
Bovine Serum Albumin ◽  
Dna Adducts ◽  
Human Exposure ◽  
Limit Of Detection ◽  
Serum Samples ◽  
Bovine Serum Albumin Conjugate ◽  
Aflatoxin B

ABSTRACT Mouse monoclonal antibodies were developed against a synthetic aflatoxin B1 (AFB)-lysine–cationized bovine serum albumin conjugate. The isotype of one of these antibodies, IIA4B3, has been classified as immunoglobulin G1(λ). The affinity and specificity of IIA4B3 were further characterized by a competitive radioimmunoassay. The affinities of IIA4B3 for AFB and its associated adducts and metabolites are ranked as follows: AFB-lysine > 8,9-dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl formamido)-9-hydroxy-AFB > AFB = 8,9-dihydro-8-(N 7-guanyl)-9-hydroxy-AFB > aflatoxin M1 > aflatoxin Q1. IIA4B3 had about a 10-fold higher affinity for binding to AFB-lysine adduct than to AFB when 3H-AFB–lysine was used as the tracer. The concentration for 50% inhibition for AFB-lysine was 0.610 pmol; that for AFB was 6.85 pmol. IIA4B3 had affinities at least sevenfold and twofold higher than those of 2B11, a previously developed antibody against parent AFB, for the major aflatoxin-DNA adducts 8,9-dihydro-8-(N 7-guanyl)-9-hydroxy-AFB and 8,9-dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl formamido)-9-hydroxy-AFB, respectively. An analytical method based on a competitive radioimmunoassay with IIA4B3 and3H-AFB–lysine was validated with a limit of detection of 10 fmol of AFB-lysine adduct. The method has been applied to the measurement of AFB-albumin adduct levels in human serum samples collected from the residents of areas at high risk for liver cancer.

Monoclonal antibodies evaluated for use in a screening assay for conjugates of human serum albumin and pyridoxal 5'-phosphate.

1989 ◽  
Vol 35 (8) ◽  
pp. 1756-1760 ◽  
Author(s):  
B B Miller ◽  
W E Turner
Keyword(s):  
Monoclonal Antibody ◽  
Monoclonal Antibodies ◽  
Human Serum Albumin ◽  
Human Serum ◽  
Limit Of Detection ◽  
Screening Method ◽  
Serum Samples ◽  
Screening Assay ◽  
Antibody Avidity ◽  
Negative Results

Abstract This enzyme immunoassay (EIA) was developed to measure pyridoxal 5'-phosphate bound to albumin (PLP-HSA) in human serum. The monoclonal antibody titer was 1:2000 and a sequential saturation analysis curve, prepared with samples containing from 10 to 1000 nmol/L, showed a 50% inhibition of antibody at 50 nmol of the conjugate per liter. The lower limit of detection for PLP-HSA was 10 nmol/L, a sensitivity 1000-fold greater than that for any potential interferent. When serum samples gave negative results in the assay, we compared the antigenicity of the principal sites for PLP binding on HSA. It was apparent that the preferred physiological site was not antigenic; however, three additional sites for PLP binding on HSA elicited comparable antibody avidity. This EIA is potentially quite sensitive and specific for PLP-HSA, but considerable additional effort is required to convert serum PLP to an HSA-bound form detectable in the assay, which limits its application as a screening method.

Monoclonal Antibody Detection of Porcine Meat

1994 ◽  
Vol 57 (2) ◽  
pp. 146-149 ◽  
Author(s):  
P. MORALES ◽  
T. GARCÍA ◽  
I. GONZÁLEZ ◽  
R. MARTÍN ◽  
B. SANZ ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Monoclonal Antibodies ◽  
Bovine Serum Albumin ◽  
Horseradish Peroxidase ◽  
Indirect Elisa ◽  
Cross Reactivity ◽  
Antibody Detection ◽  
Muscle Proteins ◽  
Elisa Format ◽  
Soya Proteins

A stable hybridoma cell line (DD9) has been produced secreting a monoclonal antibody specific for porcine muscle proteins. The DD9 monoclonal antibody (mAb) failed to show a significant cross-reactivity when tested against beef, horse, chicken, and soya proteins, as well as bovine caseins, gelatin, and bovine serum albumin. The DD9 mAb was further used in an indirect ELISA format for detection of defined amounts of porcine meat (1–100%) in beef and chicken meat mixtures immobilized on 96-well plates. Immunorecognition of monoclonal antibodies adsorbed to porcine meat was made with rabbit anti-mouse immunoglobulins conjugated to the enzyme horseradish peroxidase.

scholarly journals Development of a Sensitive Bead-Based Assay for Enhanced Monoclonal Antibody Detection

2011 ◽  
Vol 1346 ◽  
Author(s):  
Manuel E. Ruidíaz ◽  
Natalie Mendez ◽  
Ana B. Sanchez ◽  
Bradley T. Messmer ◽  
Andrew C. Kummel
Keyword(s):  
Monoclonal Antibody ◽  
Limit Of Detection ◽  
Solid Phase ◽  
Solid Phase Peptide Synthesis ◽  
Fluorescent Labeling ◽  
Antibody Detection ◽  
Serum Samples ◽  
Mimetic Peptide ◽  
Mimetic Peptides ◽  
Zero Response

ABSTRACTMonoclonal antibodies are increasingly used in the treatment of cancer due to their enhanced targeting and immune system stimulation properties. Dosage guidelines typically do not account for personal cancer load or metabolism, thereby possibly affecting treatment outcome or causing unwanted side effects. The requirement for an assay that can quickly and precisely measure the concentration of the monoclonal antibody in a serum sample of a patient during therapy is unmet. A bead-based assay with peptide antigen mimetics has been developed to rapidly determine the concentration of antibody drug present in serum specimens with high sensitivity. Alemtuzumab (anti-CD52) and rituximab (anti-CD20) antigen mimetic peptides, as discovered by phage display, were synthesized on 10 um TentaGel resin beads using conventional solid phase peptide synthesis techniques. The beads were modified to allow for multiplexing and microfluidic handling via fluorescent labeling and magnetic functionalization. The antigen-displaying fluoromagnetic particles were incubated with spiked serum samples which allowed free antibody to be captured. Primary antibody detection was performed on alemtuzumab while rituximab detection was used to compensate for non-specific serum binding to the beads. After washing, the beads were incubated with a fluorescently tagged secondary label for detection by flow cytometry. (Results) A fast, low cost, specific assay has been developed with several key techniques which allows detection at low concentration (0.1ug/ml) of spiked samples. Primary to achieving this detection limit was the implementation of a compensation scheme where two antigen mimetic peptides behave linearly (R2=0.996) which enables the calculation of the zero response of the antigen mimetic peptide of interest (alemtuzumab antigen mimetic) while measuring the zero response of the compensatory antigen mimetic peptide (rituximab antigen mimetic) during primary assay measurement. This reduces fluorescence response variation due to variations present due to sample preparation, storage and different patients because of the equivalent interactions these effects have on the compensatory beads. The developed assay is therefore robust against serum variation and enables a lower limit of detection.

scholarly journals Development of Vasoinhibin-Specific Monoclonal Antibodies

2021 ◽  
Vol 12 ◽  
Author(s):  
Nils Müller ◽  
Juan Pablo Robles ◽  
Magdalena Zamora ◽  
Johannes Ebnet ◽  
Hülya Markl-Hahn ◽  
...  
Keyword(s):  
Monoclonal Antibodies ◽  
Serum Proteins ◽  
Limit Of Detection ◽  
Sandwich Elisa ◽  
Vascular Diseases ◽  
High Specificity ◽  
Cross Reactivity ◽  
Dimensional Structure ◽  
Serum Samples ◽  
Limit Of Quantitation

Vasoinhibin is a protein hormone with antiangiogenic, antivasodilatatory, and antivasopermeability effects generated by the proteolytic cleavage of prolactin. The discovery of its role in diabetic retinopathy and peripartum cardiomyopathy led to the evaluation of new pharmacological treatments in clinical interventional trials. However, the quantitative evaluation of vasoinhibin in biological samples from patients has not been possible due to the lack of vasoinhibin-specific antibodies. Recently, loop 1 of vasoinhibin was identified to have a different three-dimensional structure compared to PRL, and thus to contain vasoinhibin-specific epitopes. Here, we report the development of two sets of vasoinhibin-specific monoclonal antibodies against two neighboring regions of the vasoinhibin loop 1. An experimental sandwich ELISA with two monoclonal anti-vasoinhibin antibodies was developed, which had no cross-reactivity to recombinant human full-length prolactin. The ELISA had a quantitation limit of 100 ng/ml, and intra-assay- and inter-assay coefficients of variation of 12.5% and 14%, respectively. The evaluation of 15 human serum samples demonstrated concentrations of below limit of detection (n=3), below limit of quantitation (n=1) and between 0.23 µg/ml (230 ng/ml) to 605 µg/ml (n=12) in the quantifiable range. Despite the high specificity of the monoclonal-monoclonal antibody sandwiches which discriminate vasoinhibin from PRL, there might be cross-reactivities by serum proteins other than vasoinhibin. A fully established vasoinhibin ELISA may support diagnostic and therapeutic measures in vascular diseases.

scholarly journals Monoclonal antibodies to a phosphoprotein from chromatin of rat liver

1985 ◽  
Vol 225 (2) ◽  
pp. 357-363 ◽  
Author(s):  
M J Halikowski ◽  
C C Liew
Keyword(s):  
Monoclonal Antibody ◽  
Monoclonal Antibodies ◽  
Bovine Serum Albumin ◽  
Rat Liver ◽  
High Specificity ◽  
Cross Reactivity ◽  
Dot Blot ◽  
Chromosomal Proteins ◽  
Rat Liver Nuclei ◽  
Liver Nuclei

Three monoclonal antibody subclasses (IgG1, IgG2a, and IgM) were raised to the phosphoprotein B2 (Mr 68000, pI6.5-8.2) which has been shown previously to be associated with the nucleosomes of rat liver nuclei. These antibodies do not show any significant cross reactivity with CM-cellulose ‘unbound’ non-histone chromosomal proteins, bovine serum albumin or histones. Further verification of the specificity of these antibodies to this phosphoprotein was carried out using both ‘dot’ blot and immunological transfer analysis (‘Western blot‘). The monoclonal antibodies (IgG1 and IgG2a) could also be used to semi-quantify the phosphoprotein B2 in rat liver nuclei. The high specificity and unlimited availability of this type of probe provides a means to study the role(s) of this phosphoprotein in the overall scheme of actively transcribed chromatin.

Pharmacokinetics (PK) of the chimeric anti-GD2 antibody, ch14.18, in children with high-risk neuroblastoma.

2012 ◽  
Vol 30 (15_suppl) ◽  
pp. 9576-9576
Author(s):  
Ami Vijay Desai ◽  
Elizabeth Fox ◽  
Theresa C. DiSipio ◽  
L. Mary Smith ◽  
Allison Lim ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
High Risk ◽  
Half Life ◽  
Limit Of Detection ◽  
Sampling Strategy ◽  
Volume Of Distribution ◽  
Plasma Samples ◽  
Limited Sampling ◽  
Dosing Strategies ◽  
Pre Treatment

9576 Background: The PK of ch14.18, a chimeric monoclonal antibody (cMoAb) that significantly improves survival in high-risk neuroblastoma, was previously reported to be highly variable in children, and its clearance (CL, 130 mL/h · m2) and volume of distribution (Vdss, 32 L/m2) were >10-fold higher than the CL and Vdss of other cMoAbs. Characterizing the PK of ch14.18 and the factors responsible for its variability could lead to alternative dosing strategies that reduce toxicity. Methods: Detailed PK sampling was performed prior to, during and for 25 d after 4 daily 10 h infusions of 25 mg/m2 of ch14.18 administered with sargramostim (ANBL0032) in children enrolled on an IRB-approved institutional correlative protocol supported by United Therapeutics Corp. Ch14.18 concentrations were measured with a validated ELISA with a lower limit of detection of 0.44 mcg/mL. PK parameters were derived using non-compartmental methods and reported as median (range). Results: 5 males and 4 females, median (range) age 3.5 (1-7) yrs, have been enrolled. Six were studied on cycle 1 (C1), 2 on C5 and 1 on C3; 3 of 6 patients studied on C1 were re-studied on C3. Data from 3 patients are not included because pre-treatment plasma samples contained a substance that interfered with the ELISA. The Cmax after the 4th daily infusion was 14 (10-24) mcg/mL, and ch14.8 was undetectable at day 25 in 3/6 patients. The half-life was 220 (120-390) h, and the CL was 11 (3.8-16) mL/h · m2, which is similar to the average CL of 4 other cMoAbs (11 mL/h · m2). The Vdss of 2.8 (1.2-3.9) L/m2 approximated blood volume and was similar to the Vdss of other cMoAbs (1.7 L/m2) and humanized MoAbs (2.8 L/m2). AUC0-∞ in 2 patients studied twice were 3440 and 1540 mcg · h/mL on C1 and 2760 and 2690 mcg · h/mL on C3. Conclusions: Ch14.18 CL, Vdss and half-life in children are similar to those in adults receiving ch14.18 at the same dose and similar to other cMoAbs. Ch14.18 PK in children was less variable than previously reported. The identity of the interfering substance in the plasma of some patients requires further investigation. A limited sampling strategy will be developed from these data for use in larger multi-institutional PK studies of ch14.18.

scholarly journals 170 Evaluation of endothelial function in dyslipidaemic patients treated with anti-PCSK9 monoclonal antibody

2021 ◽  
Vol 23 (Supplement_G) ◽  
Author(s):  
Angelicac Cersosimo ◽  
Giuliana Cimino ◽  
Ludovica Amore ◽  
Andrea Drera ◽  
Mara Gavazzoni ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Monoclonal Antibodies ◽  
High Risk ◽  
Arterial Stiffness ◽  
Secondary Prevention ◽  
Endothelial Function ◽  
Lipid Profile ◽  
Total Cholesterol ◽  
Non Invasive ◽  
Very High

Abstract Aims According to new Guidelines, the use of an anti-PCSK9 monoclonal antibody in combination is recommended in secondary prevention in patients with very high risk who do not reach the target with the maximum tolerated dose of statin and ezetimibe, and in those patients with very high-risk familial hypercholesterolemia. The therapy is always combination, while the single treatment with anti-PCSK9 monoclonal antibody is indicated in patients with statin intolerance. The present study aims to determine the cardiovascular effects that are highlighted in the treatment of dyslipidaemia with the anti-PCSK9 monoclonal antibody, especially as regards the endothelial function (using the non-invasive methods of EndoPAT), the arterial stiffness (using the non-invasive methods of SphygmoCOR) and the effective improvement on the lipid profile (reduction total cholesterol, LDL and triglycerides). Methods The study is a single-centre prospective study enrolling 47 patients in primary and secondary prevention with non-target LDL cholesterol. Patients were evaluated and enrolled from April 2019 to June 2020 (recruitment period). The average follow-up was 12 weeks, from intaking one of anti-PCSK9, Alirocumab 75 or 150 mg and Evolocumab 140 mg. The scheduled evaluations of the enrolled population were before the beginning of the therapy and after a period of 12 weeks. Results After 12 weeks of treatment we demonstrated a statistically significant reduction in total cholesterol (P < 0.001) and LDL (P < 0.001). An important effect on the inflammatory profile was highlighted, resulting in a decrease in Hs-CRP at 12-weeks (P 0.057), associated with an improvement on endothelial function (P 0.003). Reduction of arterial stiffness was no significant (P 0.238). Conclusions Data confirm anti-PCSK9 monoclonal antibodies, associated with statins and/or ezetimibe to reach LDL target, improve significantly lipid profile and endothelial function. Furthermore anti-PCSK9 monoclonal antibodies are safe and practically free of side effects.

scholarly journals Anti-Lipid A Monoclonal Antibody Centoxin (HA-1A) Binds to a Wide Variety of Hydrophobic Ligands

1998 ◽  
Vol 66 (2) ◽  
pp. 870-873 ◽  
Author(s):  
E. J. Helmerhorst ◽  
J. J. Maaskant ◽  
B. J. Appelmelk
Keyword(s):  
Molecular Weight ◽  
Monoclonal Antibody ◽  
Monoclonal Antibodies ◽  
Bovine Serum Albumin ◽  
Gel Electrophoresis ◽  
Lipid A ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Binding Properties ◽  
Antibody Epitopes

ABSTRACT This note describes the binding specificities of four lipid A monoclonal antibodies (MAbs) including Centoxin (HA-1A); these MAbs display similar binding properties. MAbs reacted with lipid A and heat-killed smooth bacteria, whereas no reactivity was observed with smooth lipopolysaccharide (LPS). Immunoblotting of bacterial extracts separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that the MAbs bound to many polypeptide bands including the molecular weight markers. Denaturation of bovine serum albumin (BSA) by boiling or dithiothreitol treatment unmasked antibody epitopes. In addition, binding both to a hydrophobic aliphatic C12 chain covalently coupled to BSA and to single-stranded DNA was observed. The polyreactivity of these clones is most likely mediated by a preferential reactivity with hydrophobic molecular patches.

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.

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