Search results for "monoclonal antibody"
showing 10 items of 356 documents
Combined heterologies for monoclonal antibody-based immunoanalysis of fluxapyroxad
2018
Nowadays, instrumental methodologies and rapid bioanalytical techniques complement each other for the analysis of toxic chemical compounds. Fluxapyroxad was commercialized a few years ago as a fungicide and today it is being used worldwide to control a variety of pests. In the present study, the development of monoclonal antibody-based immunochemical methods for the analysis of this chemical in food samples was evaluated for the first time. Novel haptens were synthesized and protein bioconjugates were prepared. High-affinity and specific monoclonal antibodies to fluxapyroxad were generated from two haptens with alternative linker tethering sites. Haptens with linker site heterology and a st…
MANOTA: a promising bifunctional chelating agent for copper-64 immunoPET
2017
International audience; Improved bifunctional chelating agents (BFC) are required for copper-64 radiolabelling of monoclonal antibodies (mAbs) under mild conditions to yield stable, target-specific imaging agents. Four different bifunctional chelating agents (BFC) were evaluated for Fab (Fragment antigen binding) conjugation and radiolabelling with copper-64. Two DOTA- (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) and two NOTA- (1,4,7-triazacyclononane-1,4,7-triacetic acid) derivatives bearing a p-benzyl-isothiocyanate group were conjugated to Fab-trastuzumab - which targets the HER2/neu receptor - and the average number of chelators attached ranged from 2.4 to 4.3 macrocycles …
Separation and purification of no-carrier-added arsenic from bulk amounts of germanium for use in radiopharmaceutical labelling
2010
AbstractRadioarsenic labelled radiopharmaceuticals could add special features to molecular imaging with positron emission tomography (PET). For example the long physical half-lives of72As (T1/2=26 h) and74As (T1/2=17.8 d) in conjunction with their high positron branching rates of 88% and 29%, respectively, allow the investigation of slow physiological or metabolical processes, like the enrichment and biodistribution of monoclonal antibodies in tumour tissue or the characterization of stem cell trafficking. A method for separation and purification of no-carrier-added (nca) arsenic from irradiated metallic germanium targets based on distillation and anion exchange is developed. It finally con…
Biosensor Analysis of β2-Glycoprotein I–Reactive Autoantibodies: Evidence for Isotype-Specific Binding and Differentiation of Pathogenic from Infecti…
2007
Abstract Background: For the laboratory diagnosis of the antiphospholipid syndrome (APS) we developed a biosensor with the ability to distinguish between disease-relevant anti-β2-glycoprotein I (β2GPI) autoantibodies (anti-β2GPI) and pathogen-specific β2GPI cross-reactive antibodies that occur transiently during infections. Methods: We used a surface plasmon resonance (SPR) biosensor device. For the detection of anti-β2GPI in serum samples, affinity-purified human β2GPI was covalently attached to a functionalized n-alkanethiol self-assembling monolayer on the biosensor chip. After verifying the specificity of the biosensor system with a panel of monoclonal antibodies to β2GPI, we analyzed s…
Functionally active complement proteins C6 and C7 detected in C6- and C7-deficient individuals
1991
SUMMARYTwo sensitive sandwich ELISAs based on monoclonal antibodies directed to native C6 and C7 allowed the detection and quantitation of these complement proteins in 20 out of 37 serum samples from individuals who had previously been classified as deficient in these proteins as assessed by immunochemical and/or functional assays. Furthermore, serum from four C6-deficient and one combined C6-/C7-deficient individual showed an increase in the terminal complement complex (TCC) and a decrease in native C6 and C7 after complement activation as assayed by specific ELISAs. Despite their (incomplete) deficiencies, these individuals therefore possess functionally active terminal complement protein…
Synthesis and Evaluation of a Novel Series of Pyrrolizine Derivatives as Dual Cyclooxygenase-1 and 5-Lipoxygenase Inhibitors
1997
The aim of our study was to investigate structure activity relationship following the replacement of the 6-phenyl substituent at the 6,7-diaryl-2,3-dihydropyrrolizine template by various heteroaromatic residues. In this context we developed a new, efficient, and highly sensitive test method for the screening of dual cyclooxygenase-1 (COX-1) and 5-lipoxygenase (5-LOX) inhibitors. We used human platelets as a source of COX-1 and human PMNLs as a source of 5-LOX. Both cell types were isolated from the same volume of blood. PGE2 and LTB4 respectively were determined by highly selective and sensitive ELISA kits, using monoclonal antibodies. For a single determination at most 0.5 mL whole blood i…
Specific immunohistochemical identification of Candida albicans in paraffin-embedded tissue with a new monoclonal antibody (1B12).
1995
In invasive candidiasis, the identification of Candida organisms in tissue samples or in normally sterile fluids is essential for an accurate diagnosis. Species identification is an important clue for the source of infection and in epidemiological studies. In this article, the authors have tested the value of a new monoclonal antibody (1B12) to detect C albicans in culture by immunofluorescence, and in tissue samples by immunohistochemistry. MAb 1B12 was found to specifically recognize C albicans , does not cross-react with other Candida species or other structurally similar fungi, and is very sensitive and specific in paraffin-embedded tissue, having no reactivity in normal human tissues o…
In Vitro Interactions of C-ANCA (Antibodies to Proteinase 3) with Human Endothelial Cells
1993
Several concepts concerning the pathogenicity of antineutrophil cytoplasmic antibodies (ANCA) exist, but till now only sparse data about ANCA-endothelial interactions are available. In this study we have investigated the expression of proteinase 3 (PR-3) in human umbilical endothelial cells (HEC) using purified anti-PR3 antibodies (C-ANCA) of patients with Wegener’s granulomatosis (WG) and monoclonal antibodies to PR-3 (human and murine) as probes. Performing cytoELISAs, laser scanning microscopy and Western blot we were able to show that treatment of HEC with IL-1-alpha led to an increased PR-3 expression in the cytoplasm and to a transient translocation into the EC-membrane. Representing …
Specific Targeting of Cytokine-Secreting Cells: A Bispecific Diabody Recognizing Human Interleukin-6 and CD3 Induces T Cell-Mediated Killing
1998
Cytokines have been implicated in the pathophysiology of many diseases. Although there have been many attempts to neutralize the activity of cytokines in vivo and in vitro, no strategies have been developed to specifically eliminate cells that overexpress cytokines. Considering the fact that cytokines in part remain cell associated on secretion, we have constructed a bispecific diabody consisting of a nonneutralizing scFv antibody recognizing human interleukin-6 (IL-6) and an scFv corresponding to the monoclonal antibody (mAb) OKT3, which recognizes and activates the human T cell receptor. Here we show that the diabody recognized both human IL-6 and human CD3. In the presence of human T cel…
Catumaxomab: a bispecific trifunctional antibody.
2009
The trifunctional bispecific monoclonal antibody catumaxomab has two binding specificities directed at epithelial cell adhesion molecule (EpCAM) and the T-cell antigen CD3. With its Fc-fragment, catumaxomab additionally binds accessory cells such as dendritic cells, macrophages and natural killer cells. The trifunctional approach thus leads to unrestricted but specific killing of epithelial tumor cells by major histocompatibility complex without the need for preactivation or external costimulation. The tumor-associated antigen EpCAM is strongly expressed in carcinomas of various origins including colon, rectum, ovarian, gastric, esophagus, lung, pancreas, breast and head and neck. Expressio…