Nanobodies, a promising tool for species-specific diagnosis of Taenia solium cysticercosis

Int J Parasitol. 2009 Apr;39(5):625-33. doi: 10.1016/j.ijpara.2008.10.012. Epub 2008 Nov 17.

Abstract

Taenia solium cysticercosis is a major helminth zoonosis in developing countries. Pigs are the intermediate hosts mediating transmission of infection. Specific assays to diagnose living cysts in pigs are lacking. The monoclonal-based antigen detection ELISA is genus-specific and cross-reactions with Taenia hydatigena hamper the use of this test to screen pigs. We, therefore, aimed to introduce nanobodies, camelid-derived single-domain antibodies specific for T. solium cysticercosis, to develop unambiguous tests. Nanobodies were cloned following immunization of two dromedaries with T. solium antigen and eight T. solium-specific nanobodies were selected after phage display. Their binding characteristics and potential for the diagnosis of porcine cysticercosis were investigated. The nanobodies do not cross-react with T. hydatigena, Taenia saginata, Taenia crassiceps or Trichinella spiralis and were categorized into four epitope-binding groups. The target protein was identified as 14kDa diagnostic glycoprotein (Ts14), but the nanobodies also reacted with other proteins of the same family. Nanobodies were tested in a sandwich ELISA with cyst fluid, and one particular nanobody detected its cognate serum antigens in a species-specific inhibition ELISA. Considering their beneficial production and stability properties, these highly specific nanobodies constitute a promising tool to diagnose cysticercosis after further improvement of the sensitivity and future assay validation.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antibodies, Helminth / biosynthesis
  • Antibodies, Helminth / genetics
  • Antibodies, Helminth / immunology*
  • Antibody Affinity
  • Antibody Specificity
  • Antigens, Helminth / blood
  • Antigens, Helminth / immunology
  • Blotting, Western / methods
  • Camelus / parasitology
  • Cross Reactions
  • Cysticercosis / diagnosis
  • Cysticercosis / parasitology
  • Cysticercosis / veterinary*
  • Enzyme-Linked Immunosorbent Assay / methods
  • Epitope Mapping / methods
  • Feasibility Studies
  • Molecular Sequence Data
  • Nanoparticles*
  • Serologic Tests / methods
  • Species Specificity
  • Swine
  • Swine Diseases / diagnosis*
  • Swine Diseases / parasitology
  • Taenia solium / immunology*

Substances

  • Antibodies, Helminth
  • Antigens, Helminth