A cDNA was isolated from a cDNA expression library using serum
prepared against a high molecular mass fraction of
Fasciola hepatica excretory–secretory products. The full-length
cDNA encodes a member of the recently described
peroxiredoxin antioxidant family. Peroxiredoxin could be the major
hydrogen peroxide removing antioxidant in F.
hepatica since this parasite does not express a catalase and
expresses little glutathione peroxidase activity. This novel
antioxidant may be involved in functions such as protection against
reactive oxygen species (ROS) generated by metabolic
processes and/or protection of the parasite against ROS released
by immune effector cells.