Immunogenic Cu 2+ -induced Biopolymer Systems Comprising a Steroid Hormone,Protein Antigen,and Synthetic Polyelectrolytes

We have synthesized the 17β-estradiol comprising polycomplexes by the Cu²⁺-mediated complex formation of polyanionic polyelectrolyte (PE), [polyacrylic acid (PAA), nontoxic copolymers (CP) of acrylic acid with N-isopropylacrylamide and N-vinylpyrolidine] with BSA-estradiol covalent conjugates at the relatively low concentrations of metal ions in neutral water. Cu²⁺ ions in the composition of biopolymer systems act as "fasteners" between macromolecules of same (negatively) charged polyanionic PE with protein carrier, promoting the formation of relatively stable polycomplex particles in physiological conditions. These hapten- and protein comprising Biopolymer Systems possess simultaneously highly estradiol and BSA-specific immunogenicity without traditional adjuvants after a single intravenous immunization of mice. The obtained results are of interest for the construction of polydeterminant immunogen and vaccines based on polymer derivatives of steroid hormones.