Abstract text
Introduction: Despite its importance as a widespread public health threat, Echinococcus sp. is one of the 20 Neglected Tropical Diseases (NTDs) targeted by the WHO for control and eradication. Echinococcosis has a global economic impact on both human and livestock health, as well as food security. The gold standard for echinococcosis diagnosis is the use of imaging technologies such as CAT, MRI or Ultrasonography. However, such methods are not widely available in endemic countries. Therefore, cheaper test such as serology would be an advantage. However, such tests, usually based on IgG detection, are unreliable due to low specificity. Despite the central role of IgE responses in metazoan parasite infections, this isotype has not been used for diagnostic purposes of Echinococcosis. Therefore, we are developing a highly sensitive and specific serological assay based on humanised and caninised rat basophil leukaemia (RBL) IgE reporter cell lines.
Materials and methods: We nucleofected RBL-NPY-mRFP cells with 3 constructs, expressing the wild type dog FceR1a, a chimeric Dog/Rat FcεRIα and a wild type dog FcεRIα chain in which three potential endoplasmic reticulum retention signals have been removed.
Results: Successful transfection of these cells with the 3 constructs was verified by PCR and in the next step its functionality will be tested through functional assays. The second part of the project involves the choice and recombinant expression of suitable diagnostic antigens. As the reporter assay relies on detection of antigen-specific IgE, we need to select parasitic antigens that are the target of an IgE response (i.e. allergens). After a bioinformatics assessment of predicted allergens of Echinococcus granulosus and synthesis of the corresponding cDNA, we are expressing these antigens/allergens using HEK2936E cells grown in suspension.
Conclusion: Once developed, the RBL-NPY-mRFP expressing dog FcεRIα will be assessed for its performance and compared to available serological techniques.