Hopes rise of a Covid-19 vaccine breakthrough as TWO trials in the UK and US show volunteers injected with experimental jabs have signs of immunity against the disease.

Teams from Oxford University and the American pharmaceutical company Moderna have both revealed people in their studies are showing signs of immunity.

And experts at Moderna, based in Cambridge, Massachusetts, said participants in their trial - of a different type of vaccine - all successfully developed antibodies.

The vaccines work by tricking the body into thinking it's infected with Covid-19 and causing it to produce immune substances that have the ability to destroy it.

While early research focused on antibodies, scientists are increasingly turning to a type of immunity called T cell immunity — which is controlled by white blood cells — which has shown signs of promise.

One source on the Oxford project told ITV News: 'An important point to keep in mind is that there are two dimensions to the immune response: antibodies and T-cells.

'Everybody is focused on antibodies but there is a growing body of evidence suggesting that the T-cells response is important in the defence against coronavirus.'