title: Mapping of IgE-binding epitopes on the recombinant major group I allergen of velvet grass pollen, rHol l 1.
abstract: BACKGROUND
  New and more successful approaches to diagnosis and therapy of allergic diseases require a more subtle understanding of the structure and the epitopes on the allergen molecule.
  
  
  OBJECTIVE
  This study was done to obtain more information on the structure and the IgE-binding epitopes of a major allergen of velvet grass pollen, Hol l 1.
  
  
  METHODS
  We cloned Hol l 1 from a complementary DNA library and performed B-cell epitope mapping with 21 recombinant fragments expressed as fusion proteins in Escherichia coli. The fragments were analyzed by Western blotting with sera from 50 different patients.
  
  
  RESULTS
  The patients' sera individually recognized at least four different IgE-binding regions (amino acids 1 to 27, 61 to 76, 84 to 105, and 158 to 240). According to their binding patterns with these epitopes, they were divided into five groups. Most sera (92%) bound to the C-terminal peptide (158 to 240), which consists of more than 80 amino acids, whereas there was virtually no binding to smaller fragments covering this region. In contrast to the C-terminal peptide, the IgE-binding peptides on the N terminus and on the middle region of the molecule were of a smaller size (15 to 30 amino acids).
  
  
  CONCLUSIONS
  The major group I allergen of velvet grass bears at least four different IgE-binding epitopes, which were individually recognized by sera from different patients. The C terminus represents the major IgE-binding region and contains at least one discontinuous IgE-binding epitope, whereas the N terminus and middle region of Hol l 1 seem to contain continuous IgE-binding epitopes.
authors.affiliation: Forschungszentrum Borstel, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Schramm
authors.forename: A
authors.initials: A
authors.lastname: Bufe
authors.forename: A
authors.initials: A
authors.lastname: Petersen
authors.forename: H
authors.initials: H
authors.lastname: Haas
authors.forename: M
authors.initials: M
authors.lastname: Schlaak
authors.forename: W M
authors.initials: WM
authors.lastname: Becker
mesh_terms: D000485:Allergens / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics; D000595:Amino Acid Sequence; D052179:Antigens, Plant; D001483:Base Sequence; D001666:Binding Sites, Antibody; D018076:DNA, Complementary / Q000302:isolation & purification; D018604:Epitope Mapping; D018985:Epitopes, B-Lymphocyte / Q000737:chemistry; D006023:Glycoproteins / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology*; D006801:Humans; D007073:Immunoglobulin E / Q000378:metabolism*; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics / Q000276:immunology; D010940:Plant Proteins / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology*; D006109:Poaceae / Q000737:chemistry / Q000276:immunology; D011058:Pollen / Q000737:chemistry* / Q000276:immunology; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000276:immunology*
chemical_list: D000485:Allergens; D052179:Antigens, Plant; D018076:DNA, Complementary; D018985:Epitopes, B-Lymphocyte; D006023:Glycoproteins; C100985:HOL L 1 protein, Holcus lanatus; D010446:Peptide Fragments; D010940:Plant Proteins; D011994:Recombinant Proteins; D007073:Immunoglobulin E