10 meter long, 25 year old tape worms living in human and animal digestive systems are the subjects for the latest research project at the University of Wales, Aberystwyth (UWA).
A group of scientists led by Dr Peter Brophy and Professor John Barrett of the University`s Institute of Biological Sciences are taking a new perspective on how parasitic worms survive for long periods of time within their human and animal hosts. The work is supported by the Biotechnology and Biological Sciences Research Council who are providing a £231,512 grant to fund the study.
"Whilst some UK research groups are looking at the problem via the hosts` perspective – that there are `wormy` animals/humans particularly prone to infection and what factors trigger the expulsion of the worm from the host – we are looking at the problem from the worm`s point of view," says Dr Brophy.
"We will be investigating which components (proteins) in the parasitic worms are crucial in helping it to survive for very long periods, sometimes for many years, in the highly toxic environment of the human and animal intestine ."
In Britain children can accidentally pick up roundworm eggs (Toxocara) from their pet dogs and cats or from playing on contaminated ground. Infection results in non-specific symptoms ranging from stomach upsets to asthma. Very occasionally, the resultant migrating worms lead to blindness.
The pinworm (threadworm) is one of the most common infections in the UK, with estimates of around 25% of children suffering at one time. The worms cause embarrassing itching but do not cause serious disease.
Tapeworms can live up to twenty-five years in the human intestine and be acquired from eating undercooked pork and beef. Fortunately, these are much less common in the UK than pinworms. In some farming communities accidental human infection with the dog tapeworm (hydatid) continues to be reported, as do sporadic outbreaks of liver-fluke worm disease throughout the UK.
The Parasitology group at Aberystwyth are world leaders in the application of new techniques to the study of parasitic worm infection, and one of the group, Dr Jim Jefferies, provides an on-line tutorial for other scientists worldwide in one of these laboratory tools called proteomics. See http://www.aber.ac.uk/parasitology/Proteome/Proteome.html .
The parasitology group will be utilising information from the completed genome project of the model nematode worm Caenorhabditis elegans. This has generated a database of predicted proteins, but scientists now need to link these proteins with their actual biological functions.
"Proteomics is also a powerful tool which will enable us to identify for the first time which proteins enable parasites to establish a long or chronic infection, and in doing so we will be able to identify new strategies and targets to control these parasite infections," says Dr Brophy.
"These key proteins could also provide important clues to how humans attempt to ward off chemical toxins, including those associated with many forms of cancers and ageing. The worm proteins could effectively be described as `Parasite anti-ageing creams`!
◊ A public release from University of Wales in December 2001, viewed from biologyonline.com.