title: Aldehyde modification of peptide immunogen enhances protein-reactive antibody response to toxic shock syndrome toxin-1.
abstract: Introduction of aldehyde groups into protein conjugates enhanced the immune response to a coupled peptide without the use of strong adjuvants. Synthetic peptides representing the N-terminal (residues 1-16) and internal (residues 53-65) epitopes of toxic shock syndrome toxin-1 (TSST-1) were coupled to carrier protein, and carbonyl tags were introduced by Amadori reaction with glycolaldehyde. Modified and unmodified antigens in alum were used to immunize rabbits and the reactivities of antisera were compared. Aldehyde modification augmented the response detected by ELISA, which included enhanced binding to peptides and to native TSST-1. In western blot, TSST-1 was detected by antiserum elicited to the N-terminal peptide, but not that generated to the peptide representing the internal sequence. The same antiserum also neutralized TSST-1 activity in a lymphocyte proliferation assay. The circular dichroism spectrum of the N-terminal peptide indicated a propensity for helical conformation, similar to the structure at the corresponding sequence of the native protein. These data suggest that aldehyde modification can boost immunogenicity of peptide-based vaccines, generating epitope-specific immune responses against the cognate protein antigens without using potent adjuvants.
authors.affiliation: Universita' degli Studi della Basilicata, Department of Chemistry, Potenza, Italy.
authors.forename: Alfonso
authors.initials: A
authors.lastname: Bavoso
authors.forename: Angela
authors.initials: A
authors.lastname: Ostuni
authors.forename: Jolanda
authors.initials: J
authors.lastname: De Vendel
authors.forename: Francesco
authors.initials: F
authors.lastname: Pollaro
authors.forename: Francesca
authors.initials: F
authors.lastname: Armentano
authors.forename: Thomas
authors.initials: T
authors.lastname: Knight
authors.forename: Sudesh
authors.initials: S
authors.lastname: Makker
authors.forename: Alfonso
authors.initials: A
authors.lastname: Tramontano
mesh_terms: D000447:Aldehydes / Q000737:chemistry; D000595:Amino Acid Sequence; D000818:Animals; D001427:Bacterial Toxins / Q000276:immunology / Q000633:toxicity; D015153:Blotting, Western; D049109:Cell Proliferation / Q000187:drug effects; D002942:Circular Dichroism; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000737:chemistry / Q000276:immunology; D007106:Immune Sera / Q000276:immunology; D008214:Lymphocytes / Q000166:cytology / Q000187:drug effects; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D010455:Peptides / Q000138:chemical synthesis* / Q000737:chemistry / Q000276:immunology; D011817:Rabbits; D013211:Staphylococcus aureus / Q000276:immunology
chemical_list: D000447:Aldehydes; D001427:Bacterial Toxins; D000939:Epitopes; D007106:Immune Sera; D010455:Peptides