title: An experimental and modeling-based approach to locate IgE epitopes of plant profilin allergens.
abstract: BACKGROUND
  Plant profilins are actin-binding proteins that form a well-known panallergen family responsible for cross-sensitization between plant foods and pollens. Melon profilin, Cuc m 2, is the major allergen of this fruit.
  
  
  OBJECTIVE
  We sought to map IgE epitopes on the 3-dimensional structure of Cuc m 2.
  
  
  METHODS
  IgE binding to synthetic peptides spanning the full Cuc m 2 amino acid sequence was assayed by using a serum pool and individual sera from 10 patients with melon allergy with significant specific IgE levels to this allergen. Three-dimensional modeling and potential epitope location were based on analysis of both solvent exposure and electrostatic properties of the Cuc m 2 surface.
  
  
  RESULTS
  Residues included in synthetic peptides that exerted the strongest IgE-binding capacity defined 2 major epitopes (E1, consisting of residues 66-75 and 81-93, and E2, consisting of residues 95-99 and 122-131) that partially overlapped with the actin-binding site of Cuc m 2. Two additional epitopes (E3, including residues 2-10, and E4, including residues 35-45) that should show weaker putative antigen-antibody associations and shared most residues with synthetic peptides with low IgE-binding capacity were predicted on theoretical grounds.
  
  
  CONCLUSIONS
  Strong and weak IgE epitopes have been uncovered in melon profilin, Cuc m 2.
  
  
  CONCLUSIONS
  The different types of IgE epitopes located in the 3-dimensional structure of melon profilin can constitute the molecular basis to explain the sensitization and cross-reactivity exhibited by this panallergen family.
authors.affiliation: Unidad de Bioquímica, Departamento de Biotecnología, E. T. S. Ingenieros Agrónomos, Madrid, Spain.
authors.forename: Gema
authors.initials: G
authors.lastname: López-Torrejón
authors.forename: Araceli
authors.initials: A
authors.lastname: Díaz-Perales
authors.forename: Julia
authors.initials: J
authors.lastname: Rodríguez
authors.forename: Rosa
authors.initials: R
authors.lastname: Sánchez-Monge
authors.forename: Jesus F
authors.initials: JF
authors.lastname: Crespo
authors.forename: Gabriel
authors.initials: G
authors.lastname: Salcedo
authors.forename: Luis F
authors.initials: LF
authors.lastname: Pacios
mesh_terms: D000199:Actins / Q000737:chemistry / Q000378:metabolism; D000485:Allergens / Q000737:chemistry / Q000276:immunology*; D000595:Amino Acid Sequence; D052179:Antigens, Plant / Q000737:chemistry / Q000276:immunology*; D001666:Binding Sites, Antibody; D003429:Cross Reactions / Q000276:immunology; D000939:Epitopes / Q000737:chemistry / Q000276:immunology*; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood* / Q000737:chemistry; D018448:Models, Immunological; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000737:chemistry / Q000276:immunology*; D051304:Profilins / Q000737:chemistry / Q000276:immunology*; D017433:Protein Structure, Secondary; D055672:Static Electricity
chemical_list: D000199:Actins; D000485:Allergens; D052179:Antigens, Plant; C507132:Cuc m 2 allergen, Cucumis melo; D000939:Epitopes; D010940:Plant Proteins; D051304:Profilins; D007073:Immunoglobulin E