Haptens synthetic

Purified nucleic acids are poor immunogens but can serve as high molecular weight haptens. Synthetic RNA DNA hybrids, such as poly(A) poly(dT), can serve as immunogens (Stollar and Rashtchian, 1987) and the antiserum obtained can be absorbed with ds RNA or denatured DNA. The remaining antibodies may specifically capture hybrids from solution or in competitive ELISA test. 

Fig. 21 Cationic P( VI) hapten for biomimetic photo synthetic studies...

Cohen et al., 2007), and an improved method for coupling synthetic peptide haptens to carrier proteins (Lateef et al., 2007). 

Synthetic haptens mimicking some critical epitopic structures on larger macromolecules are often conjugated to carriers to create an immune response to the larger parent molecule. For instance, short peptide segments can be synthesized from the known sequence of a viral coat protein and coupled to a carrier to induce immunogenicity toward the native virus. This type of synthetic approach to immunogen production has become the basis of much of the current research into the creation of vaccines. 

Some synthetic carriers actually are designed to have low immunogenicity on their own to minimize the potential for antibody production against them. When a hapten is coupled to these molecules, the immune response is directed principally toward the modification, not at the carrier. This design approach guides most of the immune response toward the desired target and minimizes the production of carrier-specific antibodies. 

Only a few abzymes have reached the stage where mutagenesis is being employed to search for improved performance (Miller et al., 1997). Likewise, Hilvert is the first to have reached the stage of redesign of the hapten to attempt the production of antibodies with enhanced performance (Kast et al., 1996). So, the circle of production has now been completed for at least one example, and chemistry can start again with a revised synthetic target. 

Ross, A. H., Baltimore, D., and Eisen, H. N. (1981) Phosphotyrosine-containing proteins isolated by affinity chromatography with antibodies to synthetic hapten. Nature 294, 654-656. 

The specificity of the antiserum raised against the Lea neoglycoprotein (9) was determined by hapten-inhibition studies using synthetic oligosaccharides,72 and derivatives of bovine and horse serum-albumin to which the Lea trisaccharide had been attached.73 On the basis of hapten inhibition of precipitation, this antiserum was shown to be highly specific for the carbohydrate portion of the synthetic antigen,... 

Fig. 1.—Hapten Inhibition of the Precipitation of the Synthetic Antigen 8-Carboxy-octyl 4-Chloro-4-deoxy-0-D-galactopyranoside-BSA by Rabbit Antiserum Raised Against 8-Carboxyoctyl 0-D-Galactopyranoside-BSA (12 in Table I). [The haptens were the oj-earboxyalkyl /3-D-galactopyranosides having the aglycons (1) 8-carboxyoctyl, (2) 4-carboxybutyl, (3) 2-carboxyethyl, and (4) carboxymethyl (taken from Ref. 73).]...

It is evident, however, that the use of phage endoglycosidases can facilitate the production of series of saccharides otherwise unobtainable through either chemical degradation or synthetic procedures. Below we will illustrate with some examples the use of these saccharides as antigens as well as haptens in immunogens. 

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