title: Cross-reactive IgE antibody responses to tropomyosins from Ascaris lumbricoides and cockroach.
abstract: BACKGROUND
  Evidence indicates that infection with Ascaris lumbricoides may promote development of allergy and asthma.
  
  
  OBJECTIVE
  To study the role of tropomyosin, a pan-allergen in invertebrates, in IgE responses to A lumbricoides.
  
  
  METHODS
  Recombinant A lumbricoides and Periplaneta americana tropomyosins were expressed in Pichia pastoris. Levels of IgE to tropomyosins from A lumbricoides and P americana were determined by chimeric ELISA in sera from 119 children living in a parasite-endemic area and 112 patients with cockroach allergy from the allergy clinics. Presence of tropomyosin in A lumbricoides larvae at L3 stage was evaluated by immunofluorescence using mAb 1A6, directed against mite tropomyosin. Molecular modeling of P americana and A lumbricoides tropomyosins was performed by using the MODELLER program.
  
  
  RESULTS
  A lumbricoides tropomyosin showed 69% to 98% sequence identity to tropomyosins from other invertebrates. The predicted structure of A lumbricoides tropomyosin was similar to that of P americana tropomyosin and showed the characteristic coiled-coil structure. Strong correlation was found for IgE antibodies to tropomyosins from A lumbricoides and P americana in sera from children living in a parasite-endemic area and from patients with cockroach allergy. Larvae of A lumbricoides reacted strongly with mAb 1A6.
  
  
  CONCLUSIONS
  Tropomyosin induces IgE responses in A lumbricoides-infected children and in patients allergic to cockroach.
authors.affiliation: Department of Internal Medicine, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil.
authors.forename: Ana Beatriz R
authors.initials: AB
authors.lastname: Santos
authors.forename: Gutemberg M
authors.initials: GM
authors.lastname: Rocha
authors.forename: Constance
authors.initials: C
authors.lastname: Oliver
authors.forename: Virgínia P L
authors.initials: VP
authors.lastname: Ferriani
authors.forename: Rodrigo C
authors.initials: RC
authors.lastname: Lima
authors.forename: Mário S
authors.initials: MS
authors.lastname: Palma
authors.forename: Valéria S F
authors.initials: VS
authors.lastname: Sales
authors.forename: Rob C
authors.initials: RC
authors.lastname: Aalberse
authors.forename: Martin D
authors.initials: MD
authors.lastname: Chapman
authors.forename: L Karla
authors.initials: LK
authors.lastname: Arruda
mesh_terms: D000293:Adolescent; D000328:Adult; D000595:Amino Acid Sequence; D000818:Animals; D017164:Ascaris lumbricoides / Q000737:chemistry / Q000276:immunology*; D001249:Asthma / Q000276:immunology / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D003429:Cross Reactions; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology / Q000378:metabolism; D007073:Immunoglobulin E / Q000096:biosynthesis / Q000378:metabolism*; D008875:Middle Aged; D008969:Molecular Sequence Data; D010526:Periplaneta / Q000737:chemistry / Q000276:immunology*; D014335:Tropomyosin / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism*
chemical_list: D014335:Tropomyosin; D007073:Immunoglobulin E