title: Characterization of a peptide vaccine candidate mimicking an oligosaccharide epitope of Neisseria gonorrhoeae and resultant immune responses and function.
abstract: The 2C7 epitope is a conserved oligosaccharide structure, a part of lipooligosaccharide (LOS) on Neisseria gonorrhoeae, present in 95% of clinical gonococcal isolates. 2C7 may represent a potential candidate for an anti-gonococcal vaccine. To circumvent the limitations of saccharide immunogens in producing long lived immune responses, we identified a peptide that mimics the 2C7 epitope using a random peptide library, characterizing linear and cyclic forms and formulating a multiple antigenic peptide. The multiple antigenic peptide Octa-MAP1 was used for immunization, and elicited >or=4-fold increase in cross-reactive anti-LOS antibodies in 26 of 30 mice (87%). IgG anti-LOS antibody elicited by Octa-MAP1 immunization possessed dose-responsive direct complement (C)-dependent bactericidal activity against gonococcal strains that expressed the 2C7 epitope. These data indicate that a peptide can mimic an oligosaccharide epitope and may form the basis for the development of a vaccine candidate for human immunization against N. gonorrhoeae.
authors.affiliation: Section of Infectious Diseases, Department of Medicine, Evans Biomedical Research Center (EBRC), Boston University Medical Center, Boston, MA 02118, USA. jngampas@bu.edu
authors.forename: Jutamas
authors.initials: J
authors.lastname: Ngampasutadol
authors.forename: Peter A
authors.initials: PA
authors.lastname: Rice
authors.forename: Mary T
authors.initials: MT
authors.lastname: Walsh
authors.forename: Sunita
authors.initials: S
authors.lastname: Gulati
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000907:Antibodies, Bacterial / Q000096:biosynthesis; D001428:Bacterial Vaccines / Q000737:chemistry*; D001483:Base Sequence; D017931:DNA Primers; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000737:chemistry / Q000276:immunology*; D005434:Flow Cytometry; D051379:Mice; D008969:Molecular Sequence Data; D009344:Neisseria gonorrhoeae / Q000276:immunology*; D009844:Oligosaccharides / Q000737:chemistry*
chemical_list: D000907:Antibodies, Bacterial; D001428:Bacterial Vaccines; D017931:DNA Primers; D000939:Epitopes; D009844:Oligosaccharides