Fasciola hepatica: The therapeutic potential of a worm secretome

► Within hours of infection, Fasciola hepatica suppresses host protective immune responses. ► Administration of Fasciola excretory/secretory products mimics the immune modulatory properties of live infection. ► Fasciola excretory/secretory products prevent the development of type 1 diabetes in mice. ► Cathepsin L1 secreted by F. hepatica prevents the activation of pro-inflammatory macrophages. ► Fasciola hepatica peroxiredoxin converts macrophages to an M2 phenotype. ► Fasciola helminth defence molecule-1 inhibits the processing and presentation of antigen by macrophages.