title: Screening and identification of mimotopes of the major shrimp allergen tropomyosin using one-bead-one-compound peptide libraries.
abstract: The one-bead-one-compound (OBOC) combinatorial peptide library is a powerful tool to identify ligand and receptor interactions. Here, we applied the OBOC library technology to identify mimotopes specific to the immunoglobulin E (IgE) epitopes of the major shellfish allergen tropomyosin. OBOC peptide libraries with 8-12 amino acid residues were screened with serum samples from patients with shellfish allergy for IgE mimotopes of tropomyosin. Twenty-five mimotopes were identified from the screening and their binding reactivity to tropomyosin-specific IgE was confirmed by peptide ELISA. These mimotopes could be divided into seven clusters based on sequence homology, and epitope mapping by EpiSearch of the clustered mimotopes was performed to characterize and confirm the validity of mimotopes. Five out of six of the predicted epitopes were found to overlap with previously identified epitopes of tropomyosin. To further confirm the mimicry potential of mimotopes, BALB/c mice were immunized with mimotopes conjugated to keyhole limpet hemocyanin and assayed for their capacity to induce tropomyosin-specific antibodies. BALB/c mice that received mimotope immunization were found to have an elevated level of tropomyosin-specific immunoglobulin G, but not mice that received an irrelevant mimotope. This study pioneers the successful application of the OBOC libraries using whole sera to screen and identify multiple shrimp allergen mimotopes and validates their mimicry potential using in vitro, in vivo, and in silico methods.Cellular & Molecular Immunology advance online publication, 14 september 2015; doi:10.1038/cmi.2015.83.
authors.affiliation: School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, China.
authors.forename: Nicki Yh
authors.initials: NY
authors.lastname: Leung
authors.affiliation: School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, China.
authors.forename: Christine Yy
authors.initials: CY
authors.lastname: Wai
authors.affiliation: Department of Pediatrics and Adolescent Medicine, Queen Mary Hospital, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
authors.forename: Marco Hk
authors.initials: MH
authors.lastname: Ho
authors.affiliation: Department of Biochemistry and Molecular Medicine, University of California, Davis, CA 95616, USA.
authors.forename: Ruiwu
authors.initials: R
authors.lastname: Liu
authors.affiliation: Department of Biochemistry and Molecular Medicine, University of California, Davis, CA 95616, USA.
authors.forename: Kit S
authors.initials: KS
authors.lastname: Lam
authors.affiliation: Division of Rheumatology/Allergy, School of Medicine, University of California, Davis, CA 95616, USA.
authors.forename: Jin Jun
authors.initials: JJ
authors.lastname: Wang
authors.affiliation: Division of Rheumatology/Allergy, School of Medicine, University of California, Davis, CA 95616, USA.
authors.forename: Shang An
authors.initials: SA
authors.lastname: Shu
authors.affiliation: School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, China.
authors.forename: Ka Hou
authors.initials: KH
authors.lastname: Chu
authors.affiliation: Division of Rheumatology/Allergy, School of Medicine, University of California, Davis, CA 95616, USA.
authors.forename: Patrick Sc
authors.initials: PS
authors.lastname: Leung
mesh_terms: D000485:Allergens / Q000276:immunology*; D000595:Amino Acid Sequence; D000818:Animals; D020650:Combinatorial Chemistry Techniques; D004797:Enzyme-Linked Immunosorbent Assay; D018604:Epitope Mapping; D000939:Epitopes / Q000737:chemistry / Q000276:immunology*; D006801:Humans; D007114:Immunization; D007073:Immunoglobulin E / Q000276:immunology; D007074:Immunoglobulin G / Q000276:immunology; D008403:Mass Screening; D008807:Mice, Inbred BALB C; D008863:Microspheres; D008958:Models, Molecular; D033561:Penaeidae / Q000276:immunology*; D019151:Peptide Library; D010455:Peptides / Q000276:immunology; D040681:Structural Homology, Protein; D014335:Tropomyosin / Q000276:immunology*
chemical_list: D000485:Allergens; D000939:Epitopes; D007074:Immunoglobulin G; D019151:Peptide Library; D010455:Peptides; D014335:Tropomyosin; D007073:Immunoglobulin E