Date Published: October 18, 2018
Publisher: Public Library of Science
Author(s): Ruud H. P. Wilbers, Roger Schneiter, Martijn H. M. Holterman, Claire Drurey, Geert Smant, Oluwatoyin A. Asojo, Rick M. Maizels, Jose L. Lozano-Torres, James B. Lok.
Despite causing considerable damage to host tissue at the onset of parasitism, invasive helminths establish remarkably persistent infections in both animals and plants. Secretions released by these obligate parasites during host invasion are thought to be crucial for their persistence in infection. Helminth secretions are complex mixtures of molecules, most of which have unknown molecular targets and functions in host cells or tissues. Although the habitats of animal- and plant-parasitic helminths are very distinct, their secretions share the presence of a structurally conserved group of proteins called venom allergen-like proteins (VALs). Helminths abundantly secrete VALs during several stages of parasitism while inflicting extensive damage to host tissue. The tight association between the secretion of VALs and the onset of parasitism has triggered a particular interest in this group of proteins, as improved knowledge on their biological functions may assist in designing novel protection strategies against parasites in humans, livestock, and important food crops.
Upon infection, helminth parasites establish an intricate relationship with their host. Helminths cause considerable damage during host invasion, migration through host tissues, and feeding on host cells [1, 2], but infections by these parasites can nonetheless be very persistent and last for several decades. Helminths are masters in manipulating host defense responses [1, 3], thereby creating a suitable environment for their survival and simultaneously limiting excessive damage due to host immune responses.