It involves scientists from the Francis Crick Institute, King's College London and Guy's and St Thomas' Hospital. They have looked at immune cells in the blood of 60 Covid-19 patients and found an apparent crash in the numbers of T-cells. Prof Adrian Hayday from the Crick Institute said it was a "great surprise" to see what was happening with the immune cells. "They're trying to protect us, but the virus seems to be doing something that's pulling the rug from under them, because their numbers have declined dramatically. In a microlitre (0.001ml) drop of blood, normal healthy adults have between 2,000 and 4,000 T-cells, also called T lymphocytes. The Covid patients the team tested had between 200-1,200.
snip
This research has also provided insight into the specific ways in which this disease interacts with the immune system, which Prof Hayday says will be vital as scientists around the world look for clinically valuable information. "The virus that has caused this completely Earth-changing emergency is unique - it's different. It is something unprecedented." "The exact reason for this disruption - the spanner in the works of the T-cell system - is not at all clear to us. "This virus is really doing something distinct and future research - which we will start immediately - needs to find out the mechanism by which this virus is having these effects."
