title: A hypoallergenic vaccine obtained by tail-to-head restructuring of timothy grass pollen profilin, Phl p 12, for the treatment of cross-sensitization to profilin.
abstract: Profilins are highly cross-reactive allergens in pollens and plant food. In a paradigmatic approach, the cDNA coding for timothy grass pollen profilin, Phl p 12, was used as a template to develop a new strategy for engineering an allergy vaccine with low IgE reactivity. Non-IgE-reactive fragments of Phl p 12 were identified by synthetic peptide chemistry and restructured (rs) as a new molecule, Phl p 12-rs. It comprised the C terminus of Phl p 12 at its N terminus and the Phl p 12 N terminus at its C terminus. Phl p 12-rs was expressed in Escherichia coli and purified to homogeneity. Determination of secondary structure by circular dichroism indicated that the restructuring process had reduced the IgE-reactive alpha-helical contents of the protein but retained its beta-sheet conformation. Phl p 12-rs exhibited reduced IgE binding capacity and allergenic activity but preserved T cell reactivity in allergic patients. IgG Abs induced by immunization of mice and rabbits with Phl p 12-rs cross-reacted with pollen and food-derived profilins. Recombinant Phl p 12-rs, rPhl p 12-rs, induced less reaginic IgE to the wild-type allergen than rPhl p 12. However, the rPhl p 12-rs-induced IgGs inhibited allergic patients' IgE Ab binding to profilins to a similar degree as those induced by immunization with the wild type. Phl p 12-rs specific IgG inhibited profilin-induced basophil degranulation. In conclusion, a restructured recombinant vaccine was developed for the treatment of profilin-allergic patients. The strategy of tail-to-head reassembly of hypoallergenic allergen fragments within one molecule represents a generally applicable strategy for the generation of allergy vaccines.
authors.affiliation: Christian Doppler Laboratory for Allergy Research, Division of Immunopathology, Department of Pathophysiology, Center for Physiology and Pathophysiology, Medical University of Vienna, Vienna, Austria.
authors.forename: Kerstin
authors.initials: K
authors.lastname: Westritschnig
authors.forename: Birgit
authors.initials: B
authors.lastname: Linhart
authors.forename: Margarete
authors.initials: M
authors.lastname: Focke-Tejkl
authors.forename: Tea
authors.initials: T
authors.lastname: Pavkov
authors.forename: Walter
authors.initials: W
authors.lastname: Keller
authors.forename: Tanja
authors.initials: T
authors.lastname: Ball
authors.forename: Adriano
authors.initials: A
authors.lastname: Mari
authors.forename: Arnulf
authors.initials: A
authors.lastname: Hartl
authors.forename: Angelika
authors.initials: A
authors.lastname: Stöcklinger
authors.forename: Sandra
authors.initials: S
authors.lastname: Scheiblhofer
authors.forename: Josef
authors.initials: J
authors.lastname: Thalhamer
authors.forename: Fatima
authors.initials: F
authors.lastname: Ferreira
authors.forename: Stefan
authors.initials: S
authors.lastname: Vieths
authors.forename: Lothar
authors.initials: L
authors.lastname: Vogel
authors.forename: Alexandra
authors.initials: A
authors.lastname: Böhm
authors.forename: Peter
authors.initials: P
authors.lastname: Valent
authors.forename: Rudolf
authors.initials: R
authors.lastname: Valenta
mesh_terms: D000485:Allergens / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D018926:Anti-Allergic Agents / Q000737:chemistry / Q000276:immunology*; D000906:Antibodies / Q000737:chemistry / Q000235:genetics / Q000276:immunology; D000918:Antibody Specificity / Q000235:genetics / Q000276:immunology; D000937:Antigen-Antibody Reactions; D052179:Antigens, Plant / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D001665:Binding Sites; D002942:Circular Dichroism; D000939:Epitopes / Q000276:immunology; D005818:Genetic Engineering / Q000379:methods; D006632:Histamine / Q000276:immunology; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology; D008958:Models, Molecular; D011058:Pollen / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D016133:Polymerase Chain Reaction; D051304:Profilins / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D017433:Protein Structure, Secondary; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D012680:Sensitivity and Specificity; D013601:T-Lymphocytes / Q000276:immunology; D014612:Vaccines / Q000737:chemistry / Q000235:genetics / Q000276:immunology*
chemical_list: D000485:Allergens; D018926:Anti-Allergic Agents; D000906:Antibodies; D052179:Antigens, Plant; D000939:Epitopes; D007074:Immunoglobulin G; C526193:Phl p 12 allergen, timothy grass; D051304:Profilins; D011993:Recombinant Fusion Proteins; D014612:Vaccines; D007073:Immunoglobulin E; D006632:Histamine