Anti- carbohydrates

One limitation of serum-specific IgE is that given the cross-reactivity between different Hymenoptera venoms, and also due to the presence of anti-carbohydrate antibodies, it is frequent to find several simultaneous positive results in patients with non-identified insect stings, a situation which makes diagnosis of the same difficult. In these cases, RAST inhibition and the release of histamine occasionally provide data on the venom involved and when this is not the case, it is advisable to administer immunotherapy against both [44]. 

These initial reports showed that functional carbohydrate-mimetic peptides could be found. These peptides acted as ligands for several biologically important proteins, and had potential in the development of therapeutics. Subsequently, peptides that act as molecular mimics of carbohydrates in binding to a wide variety of different receptors have been identified [ 14-44] these are summarized in Table 1 and reviewed in [ 13]. Some of these peptides were able not only to bind to a particular receptor, but also to act as immunologically functional mimics and to induce an anti-carbohydrate immune re-... 

As is documented in Table 2, the induction of anti-carbohydrate immune responses has been successfully demonstrated for many peptides. However, certain challenges remain. Often, the induced antibody titer (concentration) directed against the carbohydrate is rather weak, especially in comparison to the anti-peptide response the majority of antibodies recognize the peptide presumably in a nonmimetic conformation. Several recent studies have investigated these immime responses in more detail, with an extensive analysis of antibody isotypes and adjuvant effects [70,75], the effect of different protein carriers [194], the use of DNA vaccines [48,195], and the demonstration of protection by passive immunization [72,75,194]. In several cases, the anti-carbohydrate immune response has also been shown to be protective against infection in mice [30,72,75,78], and these cases are probably the most promising for the development of vaccines. 

With the advent of affinity chromatography to isolate enzymes [7] it was possible to adapt the method for the isolation of antibodies [8], The purification of many types of anti-carbohydrate antibodies with specificity for carbohydrate residues of macromolecules has been achieved. The antibodies were isolated by affinity chromatography on adsorbents with proper ligands. The immunodeterminants of the antigens have been found to be mono- or disaccharide residues of the antigen. The anti-carbohydrate antibodies with unique properties are useful in a variety of medicinal and technological applications. In this article the emphasis is on polyclonal antibodies specifically the preparation, properties and uses of anti-carbohydrate antibodies. 

TYPES OF ANTI-CARBOHYDRATE ANTIBODIES General Comments... 

Guar is a polysaccharide of galacto-mannan type [59], Guar was used to immunize rabbits to produce anti-carbohydrate antibodies. Inhibition experiments showed that galactose was an inhibitor but the mannose was not. Guar was subjected to periodate oxidation [37] and to oxidation by galactose oxidase [51], and in both cases the oxidized guar did not react with the... 

Antibodies directed against recombinant erythropoietin have been obtained from rabbits immunized with the hormone and Freunds complete adjuvant [64], Two sets of antibodies are present in the serum of rabbits that have been immunized, Fig. (3C). The results of oxidation of the erythropoietin with periodate, Fig. (25A), reaction of the antibodies with lectins of known carbohydrate specificity, Fig. (25B) and inhibition of the antibodies with the structural monosaccharide residues of the hormone, Fig. (26), have established the types of antibodies to be anti-carbohydrate antibodies and the immunodeterminants for these antibodies are oligosaccharides with the following structure N-acetyl neuraminyl a(2->3)... 

Antibodies with specificity for specific carbohydrate residues of antigens have been isolated from serum of rabbits immunized with carbohydrate containing antigens. Eighteen such antibodies were purified by affinity chromatography on adsorbents with ligands of carbohydrate residues. Electrofocusing results showed that all the antibodies occurred in multiprotein forms. A number of anti-carbohydrate antibodies have had useful applications. In the future additional advances with anti-carbohydrate antibodies should be made and these can lead to developments of new and improved products and processes. Some of the applications are summarized ... 

All the anti-carbohydrate antibodies purified by affinity chromatography are isomers of a different number of isoforms. The forms can be separated by electrofocusing and all have been found to have combining activity for the immunodeterminant of the same antigen by the method of coupled analysis of electrofocusing and agar diffusion [88], The isoforms of antimonosaccharide antibodies are shown in Fig. (48). 

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