Immune Response to 17β-Estradiol Involved in Polymer Gels: Antigen Specificity and Affinity of Hybridoma Clones

Abstract

The immunogenic properties of 17beta-estradiol, immobilized in negatively charged polymer gels, were investigated, and the specificity of antibodies produced was analyzed. The polymer gels developed were composed of a hydrophobic estradiol core surrounded by hydrophilic polyanions as corona. As an immunogen, it was conceived to function via a dual mode, that is as a hapten-delivery system (prolongation effect) and as a polyelectrolyte adjuvant. Polymer gels containing estradiol appeared to possess a high estradiol-specific immunogenicity even without the addition of traditional adjuvants. A comparative study of estradiol trapped in polymer gels versus estradiol conjugated to bovine serum albumin (BSA.E) + Incomplete Freund's Adjuvant (IFA) mixtures revealed similar immunogenic properties in terms of induction of specific antibodies. Following a short immunization procedure based on the use of 17beta-estradiol immobilized in polymer gels, we developed 10 specific monoclonal antibodies with Kd values ranging between 1.2 X 10(-7) and 8 X 10(-8) M.

High performance liquid chromatography study of water‐soluble complexes and covalent conjugates of polyacrylic acid with bovine serum albumin

“…The complex formation between PEs and proteins has been as subjects of numerous researches. Soluble polymer–protein complexes were studied by a wide range of methods, which are well known in colloid and polymer chemistry 13, 22–39. Interaction of polyelectrolytes with proteins in aqueous solutions is found to be sensitive to pH and ionic strength, as well as be dependent on isoelectric points of proteins 14, 37, 40.…”

“…We have been investigating the covalent conjugations of protein antigens with polyanions, such as PAA, and copolymers of acrylic acid with N ‐isopropylacrylamide and N ‐vinylpyrolidone 37, 38. It was shown for the first time that the formation of the electrostatic inter (polymer–protein) complexes in carbodiimide activated PE–protein mixtures occurs as a most rapidly proceeding process and then the condensation between carboxyl and amino groups of components (covalent conjugation) occurs.…”