Immune-system detection of virus-infected cells
In 1996, Peter C. Doherty and Rolf M. Zinkernagel won a Nobel Prize for their work on the T-lymphocytes of the immune system.
When attacked by a virus, our immune system can mount a range of responses. One such response involves a certain type of white blood cell, the T-lymphocyte, which is capable of killing virus-infected cells. In the 1970s, Peter C. Doherty and Rolf M. Zinkernagel studied the immune responses of mice to uncover how T-lymphocytes decide which cells to kill and which to spare.
The pair found that T-lymphocytes only kill virus-infected cells if they come from the same organism: one mouse’s T-lymphocyte will not kill another mouse’s infected cell. So T-lymphocytes must have a method of simultaneously recognising viral infection and also recognising cells as ‘self’.
With further experiments, it became clear that certain viral proteins were ‘presented’ by infected cells to the T-lymphocytes, to indicate infection. It also became clear that the major histocompatibility complex (HLA), which had been known to play a part in transplant rejection, allows our T-lymphocytes to recognise our own cells in normal immune responses.
Doherty and Zinkernagel’s work provided important insights into a vital part of our immune system. It had a huge impact on the development of therapies, such as vaccines, to aid the immune system in combating infection, and influenced research into dysfunction of the immune system in autoimmune diseases.