title: Identification and Characterization of IgE-Binding Tropomyosins in Aedes aegypti.
abstract: BACKGROUND
  The mosquito Aedes aegypti is a potential source of important clinically relevant allergens. However, the allergenicity and cross-reactivity of most of these has not been fully described.
  
  
  METHODS
  Natural wild-type mosquito tropomyosin was purified by size exclusion and anionic-exchange chromatography from an A. aegypti extract. Further characterization was accomplished by MALDI-TOF/TOF. Two recombinant variants of tropomyosin were obtained by expression in Escherichia coli. Specific IgE measurement by ELISA and skin tests for mosquito extract were performed in 12 patients with asthma or allergy rhinitis residing on the Caribbean island of Martinique. Cross-reactivity between natural A. aegypti tropomyosin and recombinant tropomyosins from A. aegypti, house dust mite, shrimp and Ascaris lumbricoides was analyzed by ELISA competition.
  
  
  RESULTS
  Four variants of natural tropomyosin were purified. A band of 32 kDa in SDS-PAGE representing 2 tropomyosin variants (Aed a 10.0101 and Aed a 10.0201) reacted with specific IgE of 4 of the 12 (33%) allergic patients and with rabbit polyclonal anti-shrimp tropomyosin. A high degree of cross-reactivity (60-70%) was detected between natural mosquito tropomyosin and Blo t 10, Der p 10 and Lit v 1, and a lower degree with Asc l 3 from A. lumbricoides (<30%). rAed a 10.0101 inhibited IgE binding to natural A. aegypti tropomyosin; however, rAed a 10.0201 showed a low inhibitory capacity.
  
  
  CONCLUSIONS
  Tropomyosin is a new IgE-binding protein from A. aegypti. Two of the 4 variants identified showed different degree of cross-reactivity with tropomyosins from other arthropods. The potential allergenic role of each variant should be further investigated.
authors.affiliation: Institute for Immunological Research, University of Cartagena, Cartagena, Colombia.
authors.forename: José Fernando
authors.initials: JF
authors.lastname: Cantillo
authors.forename: Leonardo
authors.initials: L
authors.lastname: Puerta
authors.forename: Sylvie
authors.initials: S
authors.lastname: Lafosse-Marin
authors.forename: Jose Luis
authors.initials: JL
authors.lastname: Subiza
authors.forename: Luis
authors.initials: L
authors.lastname: Caraballo
authors.forename: Enrique
authors.initials: E
authors.lastname: Fernández-Caldas
mesh_terms: D000293:Adolescent; D000328:Adult; D000330:Aedes / Q000276:immunology* / Q000378:metabolism*; D000485:Allergens / Q000276:immunology / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D002648:Child; D002675:Child, Preschool; D003429:Cross Reactions / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology / Q000378:metabolism; D007073:Immunoglobulin E / Q000276:immunology* / Q000378:metabolism*; D008297:Male; D011485:Protein Binding; D020543:Proteome; D040901:Proteomics / Q000379:methods; D014335:Tropomyosin / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism*; D055815:Young Adult
chemical_list: D000485:Allergens; D020543:Proteome; D014335:Tropomyosin; D007073:Immunoglobulin E