Istvan Toth
The University of Queensland, Australia
Title: Self-adjuvanting vaccine design to control fertility and prevent infectious diseases
Biography
Biography: Istvan Toth
Abstract
Immunocastration using gonadotropin-releasing hormone (GnRH)-based vaccines has been investigated in rams to control fertility. A GnRH-lipopeptide vaccine (GnRH-LP) including two copies of GnRH, lipids (2-amino-D, L-hexadecanoic acid), and a ram specific T helper epitope, was designed and synthesised. Rams were vaccinated with or without additional adjuvant. In both groups anti-GnRH antibodies were generated. Additionally rams showed a marked decrease in testicular size, providing the basis for an effective immunocastration. The attachment of synthetic lipids to peptide antigens has been shown to effectively increase the immune response to poorly immunogenic peptide antigens. Furthermore, dendritic polypeptides, polymeric nanoparticles, and carbohydrates provide multiple attachment points for peptides. The conjugation of multiple copies of a single peptide to a carrier has been demonstrated to produce higher antibody responses than a single peptide epitope. Therefore, the conjugation of the lipid core peptide (LCP) system (adjuvant) with sugar units (carrier) represents one of the most important strategies currently under investigation for drug delivery. The LCP-system has been demonstrated to adjuvant peptide epitopes from several group A streptococcal (GAS) strains. GAS is one of the most common human pathogens, and causes a wide range of infections, including: acute rheumatic fever, rheumatic heart disease, and acute glomerulonephritis. Opsonic antibodies directed against the surface M protein, a major virulence factor of GAS, mediate protection against GAS infection.