New research aids development of vaccine against Barber’s Pole worm

The vaccine has been created by the scientists at the Royal Veterinary College (RVC) in collaboration with the University of Veterinary Medicine and the University of Natural Resources and Life Sciences.

Also occasionally found in other ruminants, the Barber’s Pole worm attaches to the host animal’s stomach and feeds on blood, causing severe anaemia, swelling and, in the worst cases, death.

It is a major cause of disease and economic loss for farmers worldwide, particularly in warmer climates. Treatment of the parasite and disease control are becoming increasingly difficult to manage due to the parasite developing resistance to many of the drugs traditionally used against it.

Until now, the only available vaccines have been made by harvesting worms from the stomachs of slaughtered sheep – a time-consuming and ethically challenging process.

As part of the first study, the research team first developed a new vaccine technique by using insect cells that can generate the protective proteins normally found in the worm to act as antigens and support the animal host’s immune response.

The second study focused on testing the efficacy of the vaccine in animals. The findings of this study revealed that when given to sheep, the vaccine trains their immune system to recognise the parasite and produce protective antibodies.

The research provided promising data showing that the vaccine not only limits the ability of parasites to establish in sheep but also greatly reduces the number of eggs shed by the parasite, thereby decreasing pasture contamination.

This new method means vaccines could one day be produced without relying on slaughtered animals, making production faster, more reliable and more humane, as well as supporting global efforts to control livestock parasites.

It will also enable less reliance on chemical wormers, which are becoming less effective due to the growing drug resistance developing amongst the parasites.

Collaborative breakthrough

Professor Dirk Werling, professor of molecular immunology at the RVC and co-author of the studies, said: “This research shows that it is indeed possible to create vaccines incorporating ‘foreign’ sugars. This is an area my group has been working on for several years, and I am really pleased that we were asked to contribute with our knowledge to this ground-breaking work.

“It was absolutely amazing to collaborate with Shi and Katharina, also welcoming their two PhD students, Ms Isabella Adduci and Ms Floriana Sajovitz-Grohmann, to our lab – a collaboration which resulted in two high impact factor publications for them. It clearly shows the high quality of the work, but also how important this area is. I am looking forward to our ongoing collaboration.”

Dr Shi Yan and Dr Katharina Lichtmannsperger, scientists at the Veterinary University Vienna and senior authors of the two papers, added: “There is an increased need of effective anti-parasitic treatments against devastating gastrointestinal worms, such as Haemonchus. Developing vaccines without having to sacrifice animals is not only far more reliable, but also ethical and reproducible approach.

“Therefore, this new study provides good news that the creation of recombinant vaccines against economically important parasitic diseases, such as Haemonchus infection, is indeed possible.

“Our approach provides a proof-of-concept study but also highlights the potential of glycoengineering to deliver efficacious vaccines against multiple worm parasites in the near future. This achievement was made possible through close collaboration between basic and applied scientists and was funded by the programme ‘Top Vet Science’ by the Vetmeduni Vienna.”

This research was produced as part of the work by the RVC’s Centre for Vaccinology and Regenerative Medicine (CVRM), which was founded to pioneer the development and translation of vaccines and regenerative medicine to support both animal and human health.

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