Antibody epitope recognized

Figure 3.10. CPK rendering of the (A) proximal and (B) distal surfaces of modified CYP2C5. Antibody epitopes recognized when the protein is bound to microsomal membranes are dark gray, as reviewed in ref [40]. Several conserved amino acid side chains that have been implicated in P450 reductase interactions with CYP2B4 ° are medium gray. The orientation of the protein is similar to that depicted in Figure 3.8 with the N-terminus of the catalytic domain positioned toward the bottom of the figure.

Antibody Epitope recognized Assay system Reference... 

Antibodies are highly specific, binding only to a restricted part of a given antigen known as an epitope. Given the billions of antibody specificities that may be produced by the immune system, an antibody that recognizes an epitope on virtually any molecule may be produced. It is this property that makes antibodies immensely powerful tools for experimental, diagnostic and therapeutic procedures. 

The development of class-selective antibodies is another approach to multi-analyte analysis. The analyst may design haptens that will generate antibodies that recognize an epitope common to several compounds, as explained above for the analysis of pyrethroids by measuring PBA. Other examples of class-selective immunoassays that have been developed are mercapturates," glucuronides, pyrethroids, organophosphate insecticides, and benzoylphenylurea insecticides." ... 

Wilson, I.B.H., Harthill, J.E., Mullin, N.P., Ashford, D.A. and Altmann, F. (1998) Core al,3-fucose is a key part of the epitope recognized by antibodies reacting against plant JV-linked oligosaccharides and is present in a wide variety of plant extracts. Glycobiology 8, 651-661. 

If a monoclonal antibody was generated by immunization with a full-length native protein rather than a peptide, then the immunized mouse will generate antibodies that recognize both linear and conformationally dependent epitopes. Only a small subset of these monoclonal antibodies will likely be useful for clinical use on formalin-fixed, paraffin-embedded tissue (FFPE) samples. Those that are useful tend to have epitopes that are linear the epitopes are not dependent on the protein s three-dimensional conformation (see Chapter 16). Therefore, for antibodies generated in response to immunization with full-length proteins, the peptides that serve as positive controls will be linear stretches of amino acids derived from the native protein sequence, as listed in protein databases. 

Paraneoplastic neuropathies often occur in patients with carcinoma. Subacute sensory or sensorimotor axonal polyneuropathy, often with associated limbic encephalitis and cerebellar degeneration, is a common complication of small-cell lung cancer and other carcinomas, occasionally presenting even prior to diagnosis of the underlying neoplasm. Some patients with paraneoplastic neuropathy express anti-Hu antibodies, which recognize epitopes associated with the HuD neuronal RNA binding protein [37,38]. 

To account for the species barrier of prion infectivity, it was proposed that the 109-112 epitope recognized by antibody 3F4 is localized at the... 

Paratope The part of an antibody that recognizes the epitope, i.e., that part of the molecule of an antibody that binds to an antigen. 

Epitopes recognized by the antibody may become buried or denatured when the protein is transferred to surfaces such as nitrocellulose. This effect may be enhanced when blotting protein from SDS-containing gels. Insufficient contact between the gel and the membrane during transfer (e.g. air bubbles) will also reduce the amount of antigen available for recognition... 

Using Antibodies to Probe Structure-Function Relationships in Proteins A monoclonal antibody binds to G-actin but not to F-actin. What does this tell you about the epitope recognized by the antibody ... 

It is now possible to identify T-cell epitopes, which are recognized by receptor complexes on the T-lymphocyte surface, in addition to the B-cell epitopes recognized by antibodies (which are also the B-lymphocyte receptors). T-cells are stimulated by small peptide fragments of antigens produced by intracellular proteolytic processing, so problems of conformation do not arise, and syn-... 

Ko, A.I., Drager, U.C. and Harn, D.A. (1990) A Schistosoma mansoni epitope recognized by a protective monoclonal antibody is identical to the stage-specific embryonic antigen 1. Proceedings of the National Academy of Sciences of the United States of America 87, 4159—41 63. 

Unlike polyclonal antibodies, monoclonal antibodies are directed against single epitopes consisting of very short sequences of amino acids. These antibodies are able to provide invaluable information about the molecular conformation of a particular epitope within a given antigen. However, even though a monoclonal antibody can recognize multiple molecules, its specificity remains intact. This phenomenon is due to the presence of very similar epitopes in different peptides and proteins. This subject is discussed in detail later in this chapter. 

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