“In any immunology textbook you will read that once a virus makes it into a cell, that is game over because the cell is now infected. At that point there is nothing the immune response can do other than kill that cell,” said Leo James, who led the research team.
But studies at the Medical Research Council’s laboratory have found that the antibodies produced by the immune system, which recognise and attack invading viruses, actually ride piggyback into the inside of a cell with the invading virus.
Once inside the cell, the presence of the antibody is recognised by a naturally occurring protein in the cell called TRIM21 which in turn activates a powerful virus-crushing machinery that can eliminate the virus within two hours – long before it has the chance to hijack the cell to start making its own viral proteins. “This is the last opportunity a cell gets because after that it gets infected and there is nothing else the body can do but kill the cell,” Dr James said.