Antibodies biological activities

Enzymes, proteins, antibodies, biologically active peptides and other protein derivatives have long been used in medicinal agents. Modem biotechnology opened horizons to create new processes and products. For example insulin, interferon and other medical proteins are now being produced commercially by genetic engineering. 

Potcntiomctric Biosensors Potentiometric electrodes for the analysis of molecules of biochemical importance can be constructed in a fashion similar to that used for gas-sensing electrodes. The most common class of potentiometric biosensors are the so-called enzyme electrodes, in which an enzyme is trapped or immobilized at the surface of an ion-selective electrode. Reaction of the analyte with the enzyme produces a product whose concentration is monitored by the ion-selective electrode. Potentiometric biosensors have also been designed around other biologically active species, including antibodies, bacterial particles, tissue, and hormone receptors. 

This drug also is reported to activate macrophages, to iaduce polyclonal B-ceU activation as well as enhance specific antibody production m vivo, and to iaduce the synthesis of iaterferon and interleukin 1 (52). The iaduction of these important cytokiaes (and others) largely accounts for the profile of biological activity displayed by the pyrimidinones. Bropirimine is currentiy ia clinical evaluation for cancer, arthritis, and immunorestoration ia AIDS patients. 

Sondi, L Siiman, O. Koester, S. and Matijevic E. (2000). Preparation of Aminodextran-CdS Nanoparticle Complexes and Biologically Active Antibody-Aminodextran-CdS Nanoparticle Conjugates, Langmuir, 16, 3107-3118. 

Hirayama N, Hirano T Kohler G, Kurata A, Okumura K, Ovary Z Biological activities of anti-trinitrophenyl and antidinitrophenyl mouse monoclonal antibodies. Proc Natl Acad Sci USA 1982 79 613-615. 

SAMs was correlated to the affinities of the Fn-specific monoclonal antibodies. Although antibody-based measurements could not distinguish between conformational (structural) and orientational changes in the adsorbed proteins, they provided information about the biological activity of adsorbed proteins. 

Compared with enzymes fewer reports are available on immobilization of antibody (Ab) in sol-gels and their applications in immunosensing. Immobilization of Abs on a solid support was first reported in 1967 [128] and the technology has widespread application in affinity chromatography and other areas. However, the major problem associated with covalent immobilization of antibody on solid surface is partial loss of biological activity due to the random orientation of the asymmetric macromolecules,... 

Recombinant proteins with unique properties can potentially generate new markets and penetrate into existing markets if they can be supplied on a large scale. An ideal system would produce the safest biologically active material at the lowest cost, and would be used in combination with an inexpensive and simple purification process. So far, there have been several examples of the high-yield production of recombinant proteins in transgenic crop plants, mainly in the area of molecular medicines such as antibodies, enzymes and vaccines [45, 48-50]. Modern agricultural practices offer... 

Mammalian cell culture is more technically complex and more expensive than microbial cell fermentation. Therefore, it is usually only used in the manufacture of therapeutic proteins that show extensive and essential post-translational modifications. In practice, this usually refers to glycosylation, and the use of animal cell culture would be appropriate where the carbohydrate content and pattern are essential to the protein s biological activity, its stability or serum half-life. Therapeutic proteins falling into this category include EPO (Chapter 10), the gonadotrophins (Chapter 11), some cytokines (Chapters 8-10) and intact monoclonal antibodies (Chapter 13). 

The obvious disadvantage of immunoassays is that immunological reactivity cannot be guaranteed to correlate directly to biological activity. Relatively minor modifications of the protein product, although having a profound influence on its biological activity, may have little or no influence on its ability to bind antibody. 

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