Mini-airways of cows and pigs help prevent disease outbreaks

Animals can carry respiratory viruses that are dangerous to humans. Research associates at Wageningen University & Research are growing mini-airways from the stem cells of cows, pigs, and other types of animals in culture. They will expose these organoids to viruses or bacteria to find out whether they cause an infection. By learning more about infectious viruses and bacteria we can develop better treatments, diagnostics and vaccines to prevent large outbreaks of disease.

A hundred years ago, the world was gripped by the outbreak of a flu virus — the Spanish Flu — that was probably passed on from pigs to humans. Just two years ago we witnessed the start of a similar pandemic caused by severe acute respiratory syndrome coronavirus – type 2, a novel virus that probably originated from bats. Infection biologist Jerry Wells emphasizes “Eearly identification and understanding of pathogens and their associated infection mechanisms is important to prevent large-scale outbreaks of disease in animals and humans. This type of work used to rely on studies in experimental animals, but now also involves the use of ‘complex cell systems’.”

Study the behavior of bacteria and viruses

Microbiologist Manouk Vrieling: “We are growing mini-respiratory organs from the stem cells of cows and pigs that will be used as model systems to study the behavior of bacteria and viruses. Aline Fernandes adds “This allows us to determine the extent to which the airways of these animals are susceptible to infection.” Health services can use the outcomes to monitor specific pathogens for certain types of animals more closely and in turn potentially prevent an outbreak of disease or a pandemic.

The researchers take small sample of tissue from the airway of a cow or a pig and with the help of a matrix and specific growth factors culture a 3D airway organoid of about 1 to 2 millimetres in size. They can use this mini-airway model to determine whether a virus or bacteria enters the cells to cause infection. Additionally, they can gauge the severity of the infection by determining how well the virus can replicate in the mini-organs and how many cells are killed.
Mini-organs can help to quickly determine the extent to which new viruses can cause illness in different types of animals or in humans.
Manouk Vrieling

Swine influenza

Vrieling and her colleagues study the swine influenza virus, amongst other pathogens. “We know that certain variants of swine influenza virus cause more disease symptoms than others. At the moment, we are testing whether we can observe those differences in the infection of mini-organs,” says Vrieling. “Experiments with mini-organs could help to quickly determine the extent to which new viruses can cause illness in different types of animals or in humans. The sooner we learn this, the sooner we can intervene to protect the health of animals and humans.”

Reducing animal experiments

Although the mini-airways already consist of different cell types, the researchers in the complex cell systems consortium want to eventually combine the cell cultures with immune cells for an even better imitation of reality. Her colleague Nora Gerhards says: “With our research, we want to lead the way in making cell culture models for different animal species. This will allow us to make an important contribution to the prevention of major outbreaks of disease and at the same time help reduce the number of animal experiments. After all, you no longer need to do animal tests if they can be done on organoids.”