Researchers at the University of Dundee are using sheep in the fight against Covid-19. The flock will be used to produce antibodies against the virus, which has so far killed more than 48,000 people worldwide.

The team of 20 scientists identified 28 proteins created by SARS-CoV-2, the virus that causes Covid-19, that produce an immune response in the body. The immune reaction can lead to pneumonia and even death.

The proteins will help in developing diagnostics as well as understanding how the virus infects the body.

Harvesting antibodies

To reproduce the antibodies so they can be studied internationally, the researchers will take the genetic sequence of the virus (RNA), convert it to DNA (a double strand, rather than a single strand) and then copy it using a technique known as the polymerase chain reaction (PCR).

The process amplifies the genetic material many millions of times. The sequence is then used to program bacteria to make the proteins that make up the virus, enabling scientists to ‘harvest’ and prepare them in large amounts.

The proteins will then be introduced into sheep on a local farm, which will cause them to produce antibodies against the virus, which can be harvested from the sheep every few weeks.

The antibodies are then brought back to the laboratories in Dundee and prepared for their use. The final product will be sent to labs around the world to be used in the fight against Covid-19.

Potential applications

Paul Davies, medical research council unit manager at the University of Dundee, explained: “The antibodies that the sheep produce can be used to develop diagnostic tests. These antibodies bind very tightly to the viral proteins and do not recognise other proteins, such as the ones in our bodies.

“In the case of these antibodies, each antibody will only fit the viral protein it was designed for. This makes antibodies useful in identifying each part of the virus, as well as the complete virus, and understanding how it infects us and the best way of defeating it.

One application, for example, will be a technique that can rapidly identify the presence of the virus. This type of test can be used to determine whether the virus is present in a sample, such as a blood sample.

“The antibodies can be stuck onto a plate and the sample run over the plate. The antibodies will recognise the virus and pull it out of the sample.

“A second antibody to the virus that has a fluorescent marker is then run over the plate and the plate is washed. If the virus is present, the plate will glow.”

The discovery will also help scientists understand the basic biology of the virus and identify ways to defeat it.

“Certain parts of the virus are believed to be very important in the processes by which virus infects or attacks the lungs.

“Being able to capture and study these parts of the virus by having antibodies that specifically capture and identify them will enable us to understand this much more rapidly,” Davies added.