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

• Published in: International journal for parasitology 2009-04, Vol.39 (5), p.625-633
• Main Authors: Deckers, N., Saerens, D., Kanobana, K., Conrath, K., Victor, B., Wernery, U., Vercruysse, J., Muyldermans, S., Dorny, P.
• Format: Article
• Language: English
• Subjects: 8 kDa protein family; Amino Acid Sequence; Animals; Antibodies, Helminth - biosynthesis; Antibodies, Helminth - genetics; Antibodies, Helminth - immunology; Antibody Affinity; Antibody Specificity; Antigens, Helminth - blood; Antigens, Helminth - immunology; Biological and medical sciences; Blotting, Western - methods; Camelus - parasitology; Cross Reactions; Cysticercosis; Cysticercosis - diagnosis; Cysticercosis - parasitology; Cysticercosis - veterinary; Enzyme-Linked Immunosorbent Assay - methods; Epitope mapping; Epitope Mapping - methods; Feasibility Studies; Fundamental and applied biological sciences. Psychology; Life cycle. Host-agent relationship. Pathogenesis; Molecular Sequence Data; Nanoparticles; Pig; Protozoa; Serologic Tests - methods; Single-domain-antibodies; Species Specificity; Swine; Swine Diseases - diagnosis; Swine Diseases - parasitology; Taenia; Taenia crassiceps; Taenia solium; Taenia solium - immunology; Trichinella spiralis
• ISSN: 0020-7519; 1879-0135
• DOI: 10.1016/j.ijpara.2008.10.012

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.