Antibodies description

Wirsching, P, et al., 1995. Reactive immunization. Science 270 1775-1783. Description of reactive immunization, in which a highly reactive compound is used as antigen. Antibodies raised against such an antigen show catalytic activity for tlie chemical reaction that the antigen undergoes. 

The major enzymes used in ELISA technology include horseradish peroxidase (HRP), alkaline phosphatase (AP), (3-galactosidase (P-gal), and glucose oxidase (GO). See Chapter 26 for a detailed description of enzyme properties and activities. HRP is by far the most popular enzyme used in antibody-enzyme conjugates. One survey of enzyme use stated that HRP is incorporated in about 80 percent of all antibody conjugates, most of them utilized in diagnostic assay systems. 

The separation of a reactant system (solute) from its environment with the consequent concept of solvent or surrounding medium effect on the electronic properties of a given subsystem of interest as general as the quantum separability theorem can be. With its intrinsic limitations, the approach applies to the description of specific reacting subsystems in their particular active sites as they can be found in condensed phase and in media including the rather specific environments provided by enzymes, catalytic antibodies, zeolites, clusters or the less structured ones found in non-aqueous and mixed solvents [1,3,6,8,11,12,14-30],... 

The aim of this chapter is to discuss fluorescence concepts that are used in selected immunoassay applications. The primary focus is on fluorescence topics of recent interest that provide insight into the characteristic properties of antibodies and antigens in immunoassays, or that describe enhancements in immunoassay technologies. The basic reagents and instrumentation required for immunoassay purposes are discussed first, followed by a brief description of immunoassay formats. The principles that are utilized in various fluorescence immunoassay technologies are outlined with specific examples and their significance. Since it is beyond the scope of this chapter to review all of the applications of fluorescence immunoassays, apologies are extended to authors that this chapter fails to cite. A number of comprehensive treatments of fluorescence immunoassay (FIA) applications and related topics are available. 18 ... 

Insulin was originally (since the 1930s) obtained from porcine and bovine extracts. Bovine insulin differs from human insulin by three amino acids, and it can elicit an antibody response that reduces its effectiveness. Porcine insulin, however, differs in only one amino acid. An enzymatic process can yield insulin identical to the human form. Currently, insulin is produced via the rDNA process it was the first recombinant biopharmaceutical approved by the FDA in 1982. The recombinant insulin removes the reliance on animal sources of insulin and ensures that reliable and consistent insulin is manufactured under controlled manufacturing processes. A description of diabetes meUitus and insulin is presented in Exhibit 4.13. 

Compare and contrast the different types of antibody immunoglobulins. Provide a detailed description of the structure of the IgG antibody with particular reference to how it binds to antigens. 

In any battle, when the defence is outnumbered by the enemy, more troops are brought into the battle from the reserve. However, in the immune system, there are initially no reserve troops. When an antigen binds to its complementary antibody-receptor on B-cells, these are strongly stimulated to proliferate (clonal expansion). In addition, not only does the number of daughter cells increase but each quickly develops into what is known as an effector (or plasma) cell, in which the protein synthetic machinery increases through the development of the rough endoplasmic reticulum, so that there is a large increase in the number of antibodies synthesised and secreted. A simple description of the sequence of events is as follows ... 

Figure 333 — (A) Analyte binding to antibodies immobilized onto a sensor surface (a) and electric model used to represent it (b). (B) Illustration of the concept of electrolytic capacitor (a) schematic and (b) electric description. (C) C acitance-based immunosensor (a) vertical section (b) horizontal section 1 tantalum foil 2 tantalum oxide 3 Teflon spacer 4 Teflon plates 5 metal box. (Reproduced from [234] with permission of the American Chemical Society).

A wide range of pharmaceutical substances are derived from animal sources (Table 1.10). Many are protein-based and detailed description of products such as insulin and other polypeptide hormones, antibody preparations, vaccines, enzymes, etc., have been deferred to subsequent chapters. (Many of the therapeutic proteins are now also produced by recombinant DNA technology. Considerable overlap would have been generated had a product obtained by direct extraction from native sources been discussed here, with further discussion of a version of the same product produced by recombinant DNA technology at a later stage.) Non-proteinaceous pharmaceuticals originally derived from animal sources include steroid (sex) hormones, corticosteroids and prostaglandins. A limited discussion of these substances is presented below, as they will not be discussed in subsequent chapters. Most of these substances are now prepared synthetically. 

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