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101.
Nedonchelle E Pitiot O Vijayalakshmi MA 《Applied biochemistry and biotechnology》2000,83(1-3):287-295
Catalytic autoimmune antibodies from the sera of lupus patients were purified using histidyl-aminohexyl-Sepharose gel and
compared with the antibodies purified with protein A and protein G affinity chromatography. The IgG preparations from the
histidine affinity column had a much higher catalytic activity in hydrolyzing the peptide substrate Pro-Phe-Arg-methyl-coumarinamide
compared to the antibodies obtained by the conventional protein A/G method. This preservation of catalytic activity is attributed
to the gentle buffer conditions used in the histidine ligand method that allowed the integrity of three-dimensional structure
of purified catalytic antibodies. Thus, histidine affinity offer a superior method for isolating autoimmune catalytic antibodies. 相似文献
102.
Paul S 《Applied biochemistry and biotechnology》1998,75(1):13-24
The light (L) chain of a model antibody (Ab) was deduced to contain a serine protease-like catalytic site capable of cleaving
peptide bonds. The catalytic site is encoded by a germline VL gene. The catalytic activity can potentially be improved by somatic sequence diversification and pairing of the L chain with
the appropriate heavy chain. Autoimmune disease is associated with increased synthesis of antigen (Ag)-specific Abs, but the
reasons for this phenomenon are not known. Only recently has attention turned to the functional role of the catalytic function.
Preliminary studies confirm that the catalytic cleavage of peptide bonds is a more potent means to achieve Ag neutralization,
compared to reversible Ag binding. Administration of a monoclonal Ab to VIP in experimental animals induces an inflammatory
response in the airways, suggesting that catalytic autoantibodies to this peptide found in airway disease and lupus are capable
of causing airway dysfunction. The phenomenon of autoantibody catalysis can potentially be applied to isolate efficient catalysts
directed against tumor or microbial Ags by exposing the autoimmune repertoire to such Ags or their analogs capable of recruiting
the germline VL gene encoding the catalytic site. 相似文献
103.
104.
Monica K LittleCharlene D Crawley 《Analytica chimica acta》2002,464(1):25-35
Antibody coupled capillary electrophoresis was employed in the pre-concentration and detection of atrazine at the parts per billion (ppb) level. A 1000-fold increase in detection has been demonstrated in the use of IgG anti-atrazine monoclonal antibodies for the analysis of atrazine in well water by capillary zone electrophoresis (CZE) with UV-VIS detection. These results were confirmed by an enzyme linked immunosorbent assay (ELISA) specific for atrazine. 相似文献
105.
Aizhong Gao 《Analytica chimica acta》2007,592(1):58-63
Monoclonal antibodies (McAb) were produced to detect semicarbazide (SEM), a metabolite as a marker residue of nitrofurazone in animal food production. A carboxyphenyl derivative (CPSEM) of SEM was synthesized following derivatisation with 4-carboxybenzaldehyde (CBA). CPSEM was purified by recrystallization and conjugated to bovine serum albumin (BSA) or ovalbumin (OVA) as immunogen or coating antigen, respectively. Hybridomas were obtained by fusing mouse myeloma cells SP2/0 with splenocytes from the mice immunized with CPSEM-BSA. Hybridomas 1F10 and 4F2 secreting antibodies against CPSEM were obtained and subcloned. Ascites of monoclonal antibodies were prepared by injecting 1 × 106 cells of hybridoma 1F10 into mice abdomen. McAb obtained from hybridoma 1F10 was highly specific for CPSEM and had no cross-reaction with various nitrofuran metabolites and a range of veterinary drugs. The sensitivity of the McAb to SEM was 0.01 ng mL−1 and the IC50 value was 1.3 ng mL−1 (SEM in the form of CPSEM). McAb 1F10 is suitable to develop an immunoassay for SEM with sufficient sensitivity for monitoring nitrofurazone residues. 相似文献
106.
Recombinant antibodies for environmental analysis 总被引:1,自引:0,他引:1
Initial steps of antibody engineering in the late eighties revolutionized the technology of antibody production, particularly in the area of immunotherapy and diagnostics. Hallmarks that seemed to be out of reach for a long time are now the state of the art, e.g. tailoring of antibodies to match particular needs or by-passing immunization by use of antibody libraries. Despite the apparent benefits of recombinant antibody technologies, this field has been opened up hesitantly for other applications. This review addresses the development of recombinant antibody synthesis in environmental analysis. Examples are given of the molecular evolution of pesticide antibodies and their application for the analysis of real samples. 相似文献
107.
Roberta Collino Joël Therasse Frédéric Chaput Jean-Pierre Boilot Yves Levy 《Journal of Sol-Gel Science and Technology》1996,7(1-2):81-85
In this work we investigated the biological properties of sol-gel films in aqueous medium. Functionalized silica films were prepared by the sol-gel process, from organically modified silicon alkoxides with amino or thiol groups. Covalent binding of proteins with different orientations according to the hydrophilic or hydrophobic character of the surface was studied. This binding occurred via a covalent coupling agent providing a very stable linkage. No denaturation was detected and a good detection of the antigen was observed. Immunoassays have demonstrated the biological activity of grafted antibodies. 相似文献
108.
A polyclonal antiserum to pentachlorothiophenol-acetic acid-KLH was generated in sheep and assessed by solid phase ELISA. The assessment procedure included use of double checkerboard analysis in the absence and in the presence of analyte loads, estimation of cross reactivities of chlorophenol pesticides, assessment of the effect of pH, Tween 20, and Thames water matrix. The antiserum was highly specific for pentachlorophenol and enabled minimum detection limits of less than 0.2 ng mL–1 in river water matrix. Particularly important was the significant improvement of assay performance in the absence of Tween 20 and at pH 4 and the very low cross reactivity (less than 0.01%) for other commonly used chlorophenols—2,4,5-trichlorophenol and 2,4,6-trichlorophenol, 2-methyl-4-chlorophenoxyacetic acid, and 2,4-dichlorophenoxy acetic acid. The study re-affirms the importance of the judicious choice of hapten derivatives in the synthesis of immunogens and assay reagents for pentachlorophenol analysis by competitive immunoassays. 相似文献
109.
110.