Antigen antigenic determinant

Define the terms antibody, antigen, antigenic determinant (epitope), and immunoglobulin G. 

Induclt le biosynthesis of surface antigens Antigenic determinants frequently required... 

Definition of the association (or avidity) constant for such multivalent antibody—antigen reactions must consider not only the heterogeneity of the antibodies and the antigen determinant site(s), but also an apparent additive effect of binding two antigen molecules to a single antibody. Such effects lead... 

Figure 25.12 Structures of the A, B, and 0 blood-group antigenic determinants.

In some cases, the anionic POs adsorbed on chitin have similar antigenic determinants, but the plants belonging to different families - and even members of the same family - could have polysaccharide-specific POs with different structures. Thus, the majority of investigated species had anionic chitin-specific peroxidises, and these isoforms from potato Solcmaceae) and horseradish Brassicaceae) formed lines of precipitation with antibodies to wheat chitin-bound PO but not to anionic isoPO (Maksimov et al., 2000). However, protein extracts from several plants of Brassicaceae, Cucurhitaceae and Fahaceae formed precipitate with both the chitin-specific and anionic PO of wheat (Fig. 3). It was foimd that the greatest homology showed in plants and formed precipitation lines with the anionic PO of wheat (Tab. 2). 

CA 125 is a mucin-like glycoprotein antigenic determinant expressed on the surface of coelomic epithelium and human ovarian carcinoma cells however, it does not appear to be specific for ovarian cancer because elevated levels have been reported in breast and colorectal cancers. Studies have shown increased CA 125 levels in patients with ovarian cancer, whereas decreased CA 125 levels in chemotherapy are associated with improved possibility for survival. Some studies have shown failure of CA 125 levels to return to normal after chemotherapy, indicating... 

Moudgil, K. D., Sercarz, E. E. and Grewal, I. S. (1998), Modulation of the immunogenicity of antigenic determinants by their flanking residues , Immunol. Today, 19, 217-220. 

Van Regenmortel, M. H. V. andPellequer.J. L. (1994), Predicting antigenic determinants in proteins looking for unidimensional solutions to a three-dimensional problem Peptide Res., 7, 224 - 228. 

Kumar, V., Bhardwaj, V., Soares, L., Alexander, J., Sette, A. and Sercaz, E. (1995) Major histocompatibility complex binding affinity of an antigenic determinant is crucial for the differential secretion of interleukin 4/5 or interferon-y by T cells. Proceedings of the National Academy of Sciences USA 92, 9510-9514. 

Lobos, E. (1997) The basis of IgE responses to specific antigenic determinants in helminthiasis. ChemicalImmunology 66, 1-25. 

Hicks DJ, Johnson L, Mitchell SM, et al. Evaluation of zinc salt based fixatives for preserving antigenic determinants for immunohistochemical demonstration of murine immune system cell markers. Biotech. Histochem. 2006 81 23-30. 

Scott MD, Murad KL, Koumpouras F et al (1997) Chemical camouflage of antigenic determinants stealth erythrocytes. Proc Natl Acad Sci USA 94 7566—7571... 

Covalent attachment of antibody molecules to liposomes can provide a targeting capacity to the vesicle that can modulate its binding to specific antigenic determinants on cells or to molecules in solution. Antibody-bearing liposomes may possess encapsulated components that can be used for detection or therapy (Figure 22.17). For instance, fluorescent molecules encapsulated within antibody-targeted vesicles can be used as imaging tools or in flow cytometry... 

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