Scientists find potential toxoplasmosis drug target
Toxoplasmosis can be transmitted through soil, undercooked meat or from contact with cat faeces.
Researchers at the University of Glasgow have found a potential weakness in the Toxoplasma parasite that may eventually lead to a new drug target.
Writing in Plos Pathogens, scientists describe how they have found a key enzyme in the toxoplasmosis-causing parasite (thioredoxin) which is essential for its survival. The team are now working with industry partners to create new drugs that would target this enzyme and kill the parasite.
“More and more studies highlight the parasite’s sensitivity to redox imbalance – a key function of the enzyme we have studied,” said Dr Sheiner, from the University’s Wellcome Centre for Molecular Parasitology.
“Targeting the thioredoxin enzyme may make them vulnerable at stages of their life that are important for infection and dissemination. Finding enzymes in the parasite that we can target, and that don’t influence the human host, unravels this potentially deadly parasite’s Achilles’ heel.”
Toxoplasmosis is a common infection that is caused by the Toxoplasma parasite. It can be transmitted through soil, undercooked meat or from contact with cat faeces.
While most people who become infected with toxoplasmosis are not aware of it, the disease can be dangerous to unborn children and people with compromised immune systems.
Because the toxoplasmosis parasite is also used to learn about the biology of malaria-causing parasites, the team hope that their work will also lead to new drug targets for malaria.
Dr Sheiner said: “Our original interest in this research was not in drug discovery, rather we are excited to learn about how parasites work and how evolution provided them with special tools to serve their parasitic lifestyle. But, as in this case, we are obviously very happy if we stumble across promising targets for new drugs.”
Michael Chew, from Wellcome’s Infection and Immunobiology team, added: “Around a third of the UK population are thought to carry the Toxoplasma parasite. Normally a dormant parasite, it can lead to serious neurological harm when “awakened” in people with compromised immunity, like HIV patients, or those with an immature immune system, like infants and unborn children.
“This research is a great example of how basic, discovery science can lead to new drug targets for dangerous diseases.”
Veterinary practices are being urged to help owners safely dispose of any unused and expired pet medicines - not just antibiotics - during November's Animal Medicines Amnesty. 
