Authors

C Collett¹; R M Morphew¹; J P Dalton³; G Parry²; P M Brophy¹;  ¹ Aberystwyth University;  ² Hybu Cig Cymru Meat Promotion Wales;  ³ Queen's University Belfast

Discussion

The common liver fluke, Fasciola hepatica, threatens global food security as it causes huge agricultural losses worldwide. As a zoonotic food borne disease, fascioliasis is recognised by WHO as an emerging global public health concern. Current diagnostics are impeded by low sensitivities of faecal egg counting, influenced by irregular egg passage into faeces, and by the problematic performance in the field of commercial and in-house ELISAs for antigen and antibody detection. In the continued absence of a vaccine, control strategies rely heavily on a novel benzimidazole, triclabendazole (TCBZ), as it is the only commercially available compound active against both juvenile and adult flukes. There is an urgent drive to develop rapid diagnostics that measure both fluke presence and level of drug resistance at the penside, especially as disease modelling predicts a dramatic rise in incidence coupled with spreading TCBZ resistance. To this end, we have developed a new approach to biomarker discovery utilising proteomics to identify secreted proteins of the adult fluke TCBZ response. Our control biomarkers for fluke presence are cathepsin L proteases, major components of excretory/secretory products, and biomarkers of TCBZ-SO treatment whereby their presence indicates fluke fitness. We have raised polyclonal antibodies to a recombinant cathepsin L zymogen to confirm protein recovery from animal samples and now report progress on our biomarker validation pipeline.