College of Medical, Veterinary & Life Sciences

The University of Glasgow has received funding to repurpose drugs that are currently used to treat some parasitic diseases in humans – Sleeping Sickness, Chagas Disease and Leishmaniasis – to manage amoebic gill disease in Atlantic salmon.

Researchers hope that opening new markets for these drugs in the developed world will also help to drive down their costs in the developing world, where unaffordable healthcare can lead to many unnecessary deaths.

Neoparamoeba perurans causes amoebic gill disease (AGD) in marine phase Atlantic Salmon and is a major pathogen in salmonid aquaculture, with annual associated losses rapidly approaching those caused by sea lice. N. perurans has a unique biology that can readily exploited with tools available at the University of Glasgow.

Enclosed within the N. perurans cell is another organism called Perkinsela. Perkinsela which is a symbiont – an organism that benefits its host cell. Genome sequencing indicates that Perkinsela is closely related to a group of organisms that cause diseases in humans and domestic livestock called trypansomatids.

Using an existing state-of the-art drug discovery pipeline for trypansomatids, the researchers – Dr Martin Llewellyn and Professor Mike Barrett – propose to test the potency of existing licensed and experimental drugs against N. perurans, working on the hypothesis that killing the symbiont will lead to death of its host. A candidate drug will then be tested for activity against amoebic gill disease in vivo at a marine trial site operated by the Marine Institute, Ireland.

In addition to providing a much-needed new tool for aquaculture, the researchers believe the approach – which aims to repurpose drugs that are effective against neglected tropical disease, but which are often too expensive to deploy – has the potential drive down their cost by opening new markets for their use.

Dr Llewellyn said: “This project is a great opportunity to understand some of the science behind symbiosis, develop a much-needed drug for salmon aquaculture and also hopefully have a beneficial impact on the treatment of diseases that impact the lives of hundreds of millions of people in the tropics.”

The project, which is funded by the BBSRC, will involve a collaboration with Dr Neil Ruane at the Marine Institute, Ireland and Prof John Archibald at Dalhousie University, Canada. Industrial partners are MSD Animal Health and Scottish Sea Farms.

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First published: 4 November 2020