HAPTEN-CARRIER INTERACTIONS AND THEIR ROLE IN THE PRODUCTION OF MONOCLONAL-ANTIBODIES AGAINST HYDROPHOBIC HAPTENS

The coupling of haptens to carrier proteins is required for the genera tion of antihapten antibody response, To date, different polypeptides (such as gelatin, albumin, and keyhole limpet hemocyanin) have been us ed to increase the immune response against haptens, Different methods of conjugation have also been used to increase the specificity of the antibody response, Our results, obtained through an analysis of the an tibody response at both the polyclonal and the monoclonal levels, show that carrier proteins specifically modulate the antibody titer, the s pecificity of the response, the fusion efficiency, and the number of s pecific clones, Moreover, the affinity constants of both serum and ran domly selected hybridomas directed against different haptens have been found to be exclusively modulated by carrier proteins, In addition, t he results show that the carrier protein should be selected considerin g its possible physicochemical interaction with haptens, Data obtained suggested that any carrier is suitable for hydrophilic haptens, while the choice of the carrier for hydrophobic haptens is critical in obta ining a specific immune response, The use of specific carriers allowed the production of highly specific antibodies: even IgMs, obtained by using these carriers, were able to specifically react with hydrophobic haptens; the case of some IgM monoclonal antibodies specifically reac ting with protoporphyrin IX is reported.