Studies in large mammals offer new avenues for understanding severe Covid-19 infections and developing effective treatments.
Scientists are studying pigs to understand how Covid-19 affects humans, aiming to advance the development of vaccines and experts’ understanding of severe infection.
By introducing a human gene linked to infection with the Covid-19 coronavirus into the pigs’ DNA, researchers were able to develop animals that show symptoms and disease progression equivalent to those seen in humans.
Pigs, which are naturally resistant to Covid-19, are a useful model for studying how disease affects people, as they are mammals of comparable size and anatomy to humans.
The gene-edited pigs, developed by a team of scientists from the Roslin Institute and Moredun Research Institute, can help scientists gain a deeper understanding of the key biological processes that can trigger progression of Covid-19 from a self-limited illness to severe disease.
This research also highlights the broader potential of large animal models in biomedical research.
Large animal model
Gene-edited pigs could aid in the development of better treatments, including vaccines and antiviral drugs.
Although rodents are often used in health research, pigs provide advantages due to their similarity to humans in terms of genetics, lung structure and immune responses, the team explains.
Eight of the nine pigs in the study showed symptoms of infection akin to those observed in Covid-19, with a subset showing damage to the lungs similar to that observed in severe human cases, showing that the animal model is a valuable tool for studying the disease’s progression.
The findings suggest swift replication of the virus and immune responses in the animals, making pigs a useful model for further research, the team says.
Next steps
The ability to combine genetic engineering with real-world disease dynamics in large animal studies opens up opportunities for understanding and combating a range of respiratory illnesses, experts say.
Future research aims to explore whether these newly developed pigs can model virus spread, and co-infections with other viruses such as flu, and to develop more precise tools for studying respiratory diseases.
Future studies may seek to understand how human health conditions, such as obesity and diabetes, can worsen COVID-19 infections.
This research was published in Nature Communications, in collaboration with colleagues across the University of Edinburgh, the Moredun Research Institute, the University of Edinburgh’s Centre for Genomics and Experimental Medicine, Queen’s Medical Research Institute and the Royal Infirmary Edinburgh’s Department of Pathology.
The study was supported by UKRI Biotechnology and Biological Sciences and Wellcome. The Moredun Institute High Containment animal facilities are supported in part by Underpinning National Capacity funding from the Scottish Government Rural and Environment Science and Analytical Services (RESAS) division.
The end of the pandemic doesn’t mean the end of coronavirus research. Understanding severe disease and improving vaccines remains critical, and these pigs offer a unique avenue to do that. This study demonstrates the unique potential of large animal models in tackling complex diseases. By using pigs, we can bridge gaps left by smaller models and explore disease mechanisms in ways that directly translate to human health.
Dr Finn Grey, Senior Research Fellow, The Roslin Institute