Search results for "binding"
showing 10 items of 3896 documents
Evaluation of the concept of heterology in a monoclonal antibody-based ELISA utilizing direct hapten linkage to polystyrene microtiter plates.
2005
A series of new heterologous haptens has been synthesized and used as coating haptens in an antigen-immobilized immunoassay with a monoclonal antibody against atrazine. Coating was achieved by covalently linking the different haptens to a glutaraldehyde network directly bound to the polystyrene surface of a standard 96-well microtiter plate. With the assay designed in the antigen-immobilized format with direct chemical linkage of the hapten to the solid polystyrene surface well-defined hapten densities were achieved in all experiments. The results of different experiments with different coating haptens were comparable. Using different heterologous haptens it appears that the concept of hete…
Domains of the E1 Protein of Human Papillomavirus Type 33 Involved in Binding to the E2 Protein
1996
Papillomavirus E1 and E2 proteins are essential for the initiation of viral DNA replication. We have now analyzed the interaction of E1 and E2 of human papillomavirus type 33, which is associated with cervical carcinoma. When synthesized in insect cells using the baculovirus expression system, the E1 and E2 proteins interacted efficiently at 4 degree. A monoclonal antibody recognizing E1 amino acids 584--600 inhibited the binding of E2 and vice versa, indicating that these amino acids are involved in E2 binding. To confirm this result, a mutational analysis of E1 was performed. The E2 binding activity of E1 deletion and point mutant proteins was assayed using glutathione S-transferase E1 fu…
Benzodiazepines: specific competitors for the binding of L-tryptophan to human serum albumin.
1975
By means of the gel filtration technique, the effect of nine benzo-diazepine derivates on the binding of l-tryptophan to human serum albumin was investigated. Using equimolar tryptophan and benzodiazepine concentrations, all benzodiazepines with binding constants higher than 104 (M−1), displace l-tryptophan from its binding site to a high degree. The mechanism of the displacement was characterized as a competition for a common binding site. Some of the benzodiazepines displace l-tryptophan to a greater extent than salicylic acid. The benzodiazepines and tryptophan are the only substances known with a high degree of stereospecific binding to human serum albumin. This study shows that there i…
Design, synthesis, DNA-binding and cytotoxicity evaluation of new potential combilexines
2002
Combilexines, compounds in which a DNA intercalator is linked to a minor groove binding component, interact with the DNA in a sequence specific manner to yield in most cases compounds with anticancer activity. A series of new compounds closely related to netropsin in which the two components were linked by an amide group was synthesised as potential combilexines. As some of these compounds showed cytotoxic activity in vitro, an attempt was made to rationalise their mechanism of action. The DNA binding characteristics of the carboxamides were evaluated by thermal denaturation experiments and by ethidium bromide displacement assay. Their ability to inhibit the topoisomerase I was also determi…
Development and biological investigations of hypoxia-sensitive prodrugs of the tyrosine kinase inhibitor crizotinib
2019
Despite the huge success of tyrosine kinase inhibitors as anticancer agents, severe side effects are a major problem. In order to overcome this drawback, the first hypoxia-activatable 2-nitroimidazole-based prodrugs of the clinically approved ALK and c-MET inhibitor crizotinib were developed. The 2-aminopyridine functionality of crizotinib (essential for target kinase binding) was considered as ideal position for prodrug derivatization. Consequently, two different prodrugs were synthesized with the nitroimidazole unit attached to crizotinib either via carbamoylation (A) or alkylation (B) of the 2-aminopyridine moiety. The successful prodrug design could be proven by docking studies and a dr…
Ro 15-4513 Antagonizes Alcohol-Induced Sedation in Mice Through αβγ2-type GABAA Receptors
2011
Ethyl alcohol (ethanol) has many molecular targets in the nervous system, its potency at these sites being low compared with those of sedative drugs. This has made it difficult to discover ethanol’s binding site(s). There are two putative binding sites at gamma-aminobutyric acid (GABA) type A receptor subtypes for the proposed ethanol antagonist Ro 15-4513, the established gamma2 subunit-dependent benzodiazepine site and the recently reported delta subunit-dependent Ro 15-4513/ethanol binding site. Here, we aimed at clarifying the in vivo role of Ro 15-4513 at these two sites. We found that the antagonism of ethanol actions by Ro 15-4513 in wildtype mice was dependent on the test: an open f…
Modulation of melanoma-associated antigens by monoclonal antibodies as visualized by radioimmunoelectron microscopy and radioantibody binding assay
1987
There is a wealth of information about monoclonal antibody (MAb) specificity and function on fixed tissues, yet little is known about formation and release of antigen-antibody complexes and their functional behavior in vivo. We analyzed the pathway of radiolabeled MAbs directed against melanoma-associated antigens by radioimmunoelectron microscopy (RIEM) on metabolically active cells of the melanoma cell lines SK-MEL-28, MeWo and Colo 38 at different time intervals. In parallel, binding and release of MAbs were investigated by the radioantibody binding assay (RBA). Both procedures gave essentially concordant results. Preferentially stable binding of immune complexes (ICs) to the cell surfac…
Screening for inhibitors of HIV gp120-CD4 binding using an enzyme-linked immunoabsorbent assay.
1993
Binding of the HIV-1 major viral surface glycoprotein, gp120, to the major cell receptor, CD4, is essential for HIV infection of the target cell and syncytium formation. An enzyme-linked immunoassay using solid phase CD4 was used to quantitate the binding of HIV-1 gp120 to CD4, and to assess the activity and mechanism of action of putative inhibitors of that reaction. Monoclonal antibodies to the gp120 binding site on CD4 (e.g., Leu3a) blocked gp120 binding, while monoclonal antibodies to other portions of CD4 (e.g. OKT4) did not. Both aurintricarboxylic acid and sulfonated polysaccharides (e.g., dextran sulfate) blocked CD4-gp120 interactions by binding to the CD4 component. Human polyclon…
0135 : New regulators of iron metabolism, hepcidin and erythroferrone, in acute myocardial infarction
2016
Background Dysfunctional iron storage and transport are common in patients with chronic heart failure and associated with poor prognosis. Body iron could contribute to the pathogenesis of coronary artery disease (CAD) through its ability to induce oxidative stress. However, studies on the relationship between iron metabolism and CAD have yielded conflicting results. Patients and methods from the obseRvatoire des Infarctus de Cote d’Or (RICO) survey, 31 consecutive patients admitted in Intensive Care Unit for a first AMI were included. Serum concentrations of iron, transferrin, ferritin, the iron-regulatory hormone hepcidin and erythroferrone (a new hepcidinregulating hormone), transferrin s…
Altered Regulation of Insulin-Like Growth Factor Binding Protein-I in Patients With Polycystic Ovary Syndrome
1995
Insulin-like growth factor (IGF-I) action is influenced by circulating as well as tissue levels of its binding proteins. Because serum IGF binding protein-1 (IGFBP-1) levels have been found to be decreased in patients with polycystic ovary syndrome (PCOS), we tested the hypothesis that regulation of IGFBP-1 secretion may be different in patients with PCOS compared with normal women. We studied 15 normal ovulatory women and 15 women with PCOS of similar age (21 ± 1 and 22 ± 1 years, respectively). All subjects were studied after an overnight fast between days 5–8 after spontaneous or progestin-induced menses. Perturbations included the administration of insulin intravenously, maintenance of …