Molecular cloning and the allergenic characterization of tropomyosin from Tyrophagus putrescentiae

Protein Pept Lett. 2007;14(5):431-6. doi: 10.2174/092986607780782777.

Abstract

Storage mites have been recognized as a cause of asthma and rhinitis. Studies from several countries have shown that the IgE-mediated allergy to storage mites is of considerable importance, especially in rural populations. This study aimed to identify and characterize new allergens from Tyrophagus putrescentiae. A partial cDNA sequence encoding tropomyosin was isolated from the cDNA library by immunoscreening using anti-mouse IgG1 sera raised against T. putrescentiae whole body extract. The deduced amino acid sequence shares 64-94% identity with previously known allergenic tropomyosins. Its recombinant protein was produced by using a pET 28b expression system and purified by affinity chromatography using Ni-NTA agarose. The IgE reactivities of tropomyosins from T. putrescentiae and Dermatophagoides farinae were compared by enzyme linked immunosorbent assay (ELISA). Recombinant Tyr p 10 showed 12.5% (5/40) IgE-binding reactivity, whereas recombinant Der f 10 showed 25% (10/40) IgE-binding reactivity against the same sera from storage mite-sensitized and house dust mite-sensitized subjects. Both recombinant Tyr p 10 and Der f 10 showed little inhibition of IgE binding to T. putrescentiae crude extract by ELISA. Tropomyosin seems to contribute only a small portion of the cross-reactivity with house dust mites.

MeSH terms

  • Acaridae / chemistry*
  • Adolescent
  • Adult
  • Aged
  • Allergens / biosynthesis
  • Allergens / immunology*
  • Amino Acid Sequence
  • Animals
  • Child
  • Cloning, Molecular
  • Electrophoresis, Polyacrylamide Gel
  • Humans
  • Immunoglobulin E / metabolism
  • Mice
  • Middle Aged
  • Molecular Sequence Data
  • Recombinant Proteins / metabolism
  • Sequence Alignment
  • Tropomyosin / biosynthesis
  • Tropomyosin / immunology*

Substances

  • Allergens
  • Recombinant Proteins
  • Tropomyosin
  • Tyr p 10 allergen, Tyrophagus putrescentiae
  • Immunoglobulin E

Associated data

  • GENBANK/AY623832