title: Mutants of the major ryegrass pollen allergen, Lol p 5, with reduced IgE-binding capacity: candidates for grass pollen-specific immunotherapy.
abstract: More than 400 million individuals are sensitized to grass pollen allergens. Group 5 allergens represent the most potent grass pollen allergens recognized by more than 80 % of grass pollen allergic patients. The aim of our study was to reduce the allergenic activity of group 5 allergens for specific immunotherapy of grass pollen allergy. Based on B- and T-cell epitope mapping studies and on sequence comparison of group 5 allergens from different grasses, point mutations were introduced by site-directed mutagenesis in highly conserved sequence domains of Lol p 5, the group 5 allergen from ryegrass. We obtained Lol p 5 mutants with low IgE-binding capacity and reduced allergenic activity as determined by basophil histamine release and by skin prick testing in allergic patients. Circular dichroism analysis showed that these mutants exhibited an overall structural fold similar to the recombinant Lol p 5 wild-type allergen. In addition, Lol p 5 mutants retained the ability to induce proliferation of group 5 allergen-specific T cell lines and clones. Our results demonstrate that a few point mutations in the Lol p 5 sequence yield mutants with reduced allergenic activity that represent potential vaccine candidates for immunotherapy of grass pollen allergy.
authors.affiliation: Plant Molecular Biology and Biotechnology Laboratory, Institute of Land and Food Resources, The University of Melbourne, Parkville, Australia.
authors.forename: Ines
authors.initials: I
authors.lastname: Swoboda
authors.forename: Nicole
authors.initials: N
authors.lastname: De Weerd
authors.forename: Prem L
authors.initials: PL
authors.lastname: Bhalla
authors.forename: Verena
authors.initials: V
authors.lastname: Niederberger
authors.forename: W R
authors.initials: WR
authors.lastname: Sperr
authors.forename: Peter
authors.initials: P
authors.lastname: Valent
authors.forename: Helga
authors.initials: H
authors.lastname: Kahlert
authors.forename: Helmut
authors.initials: H
authors.lastname: Fiebig
authors.forename: Petra
authors.initials: P
authors.lastname: Verdino
authors.forename: Walter
authors.initials: W
authors.lastname: Keller
authors.forename: Christof
authors.initials: C
authors.lastname: Ebner
authors.forename: Susanne
authors.initials: S
authors.lastname: Spitzauer
authors.forename: Rudolf
authors.initials: R
authors.lastname: Valenta
authors.forename: Mohan B
authors.initials: MB
authors.lastname: Singh
mesh_terms: D000485:Allergens / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D000595:Amino Acid Sequence; D000596:Amino Acids; D052179:Antigens, Plant; D001491:Basophils / Q000276:immunology; D001665:Binding Sites; D002455:Cell Division; D002999:Clone Cells; D017124:Conserved Sequence; D018985:Epitopes, B-Lymphocyte / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification; D018984:Epitopes, T-Lymphocyte / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification; D006636:Histamine Release; D006801:Humans; D006967:Hypersensitivity / Q000517:prevention & control; D006969:Hypersensitivity, Immediate / Q000276:immunology; D007073:Immunoglobulin E / Q000276:immunology*; D016233:Immunotherapy, Active; D008129:Lolium / Q000276:immunology*; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010940:Plant Proteins / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D011058:Pollen / Q000276:immunology*; D017510:Protein Folding; D017433:Protein Structure, Secondary; D011995:Recombination, Genetic; D012867:Skin / Q000276:immunology
chemical_list: D000485:Allergens; D000596:Amino Acids; D052179:Antigens, Plant; D018985:Epitopes, B-Lymphocyte; D018984:Epitopes, T-Lymphocyte; C084941:Lol p V protein, Lolium perenne; C076049:Phl p V protein, Phleum pratense; D010940:Plant Proteins; D007073:Immunoglobulin E