摘要:

Knowledge of protein structures is important to understand protein interactions and functions in food products. Monoclonal antibodies (MAbs) can be used to detect disappearance of some epitopes and appearance of others, during physico chemical treatment, such as heating or glycosylation. Gels, foams and emulsifiants can then be quantified. MAbs prepared for other purposes could be used for the study of food quality.

ISSN:0954-0105    

DOI:10.1080/09540109609354906

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Steroids form a structurally closely related group. As a result, antibodies produced for use in immunoassays regularly show unwanted cross‐reactivities. These may be reduced by altering hapten‐protein coupling procedures, thereby reducing the exposure of the determinants giving rise to the undesirable cross‐reaction. However, these procedures can prove to be complex, expensive and not totally predictable in outcome. Exploitation of the clonal selection theory is an attractive alternative approach. The host is primed with the interfering cross‐reactant coupled to a non‐immunogenic amino acid copolymer to inactivate the B‐lymphocyte clones specific for this steroid, producing a specific immunotolerance. Then, 3 days later, the host is immunized with the steroid against which an antibody is required. The clones producing antibody to this immunogen are unaffected and the cross‐reactivity is significantly reduced or deleted. The technique has been applied to the reduction of endogenous sex steroid cross‐reactivity from antibodies prepared against synthetic and semi‐synthetic androgens (17α‐methyltestosterone, 19‐nor‐ß‐testosterone) and the progestogen medroxyprogesterone. Antibodies prepared against the synthetic oestrogen zeranol using this technique have significantly reduced its undesirable cross‐reactivity with the fungal metabolite 7α‐zearalenol. Highly specific antisera have been generated in all cases, the only adverse effect being a reduction in the titres achieved in comparison with rabbits receiving the conventional immunizing regime.

ISSN:0954-0105    

DOI:10.1080/09540109609354907

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Recombinant antibody (RAb) technology is expected to play an essential role in future food and environmental immunoanalysis. The RAb approach is not yet, however, considered as a standard method, mainly due to technical reasons. In order to establish a feasible protocol for the production of hapten specific RAbs, the essential steps of the procedure are considered in detail, especially the polymerase chain reaction amplification of antibody coding genes and the utilization of immunomagnetic selection of phages displaying selective RAbs. The synthesis of functional recombinant single‐chain Fv against s‐triazine herbicides is used as an example. Expressed RAbs are characterized by immunoassay. Although RAb‐based calibration curves were shifted toward higher concentrations by one order of magnitude, the cross‐reactivity pattern of RAbs corresponded to the original monoclonal antibodies. Sequences of different RAb clones derived from the same hybridoma line only differed in a single silent mutation. This confirms the reliability of the RAb procedure.

ISSN:0954-0105    

DOI:10.1080/09540109609354908

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Solutions of bovine myoglobin in 0.1 M‐phosphate buffer, pH 6.0, were heated over the temperature range 55–85°C for 60 min. Their immunological reactivity was tested after 0.2 μm filtration using polyclonal antibodies in the single radial immunodiffusion assay (SRID) and six monoclonal antibodies (MAbs) in a competitive and a sandwich ELISA. Reproducible results were obtained in the SRID assay (coefficient of variation (CV) = 4.0%), with a mid‐point denaturation of 79.0 ± 0.4°C. Similar results were obtained with two MAbs (mid‐point denaturation at 79.4 ± 0.5°C and 78.3 ± 0.8°C for competitive and sandwich ELISAs respectively), but the CV% values were higher (8 and 13% respectively). With the remaining four MAbs, quantification was unreliable as immunoreactivity increased during heating with large inter‐assay variations. A careful control of MAb immunoreactivity in situations covering all possible denaturation states of the test protein is an absolute prerequisite to their use in ELISAs for the immunoquantification of protein heat denaturation.

ISSN:0954-0105    

DOI:10.1080/09540109609354909

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Latex allergy is a recently increasing hazard to people who are repeatedly in contact with Latex products. Notably, with this allergy, cross‐reactivity to vegetable foods and pollen is frequently observed. It is postulated that pathogenesis‐ or, rather, defence‐related proteins induced in rubber trees are responsible for the Latex allergy and the cross‐reactivity. To evaluate this hypothesis, an esterase was selected as one of the probable defence‐related proteins in rubber Latex and its involvement in Latex allergy was investigated. The biochemical properties of a chromatographically purified esterase from ammoniated Latex were compared with those of esterases (hevains) previously purified from rubber Latex. The antigenicity of the esterase was examined by immunoblotting using sera from Latex‐allergic patients. The purified esterase (of molecular weight 80 kDa) dissociated into subunits under denaturing conditions and shared biochemical properties with hevain1from lutoids. The esterase was recognized by IgE in patients’ sera. This suggests the relevance of the purified esterase to Latex allergy.

ISSN:0954-0105    

DOI:10.1080/09540109609354910

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

The Analytical Environmental Immunochemical Consortium (AEIC) is a relatively new organization, established with the aim of promoting the use of immunochemical methods as recognized analytical tools for food and environmental testing. The members of AEIC include immunoassay kit manufacturers, agricultural and basic chemical manufacturers, immunoassay equipment manufacturers and commercial, government and academic laboratories involved in the research and development of non‐clinical immunochemical technology.

ISSN:0954-0105    

DOI:10.1080/09540109609354911

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

ISSN:0954-0105    

DOI:10.1080/09540109609354905

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor