I had suggested that one possibility for the CD8 T cells disappearing from the blood was related to them appearing in the lung. This I don’t think is correct and maybe relates to what is important into why SARS-CoV-2 becomes severe in some people.
The virus infects cells via the angiotensin converting enzyme two and this is found in many tissues such as the gut, which is why you secrete virus from your pooh and also in the lungs which is why you secrete virus when you cough.
From the research published on SARS (Severe Acute Respiratory Syndrome), it is known that CD8 T cells are improtant for removing the virus. It looks like this will be part of the story for COVID-19 virus. But in people with severe problems there is a noticable drop in these cells. If you look in the lung of the people who died with COVID19 there are few CD8 T cells in the lung. Whats the difference?.. Seems the answer is here.
Yep I now have to read Chinese…Thank heavens for Google Translate.
However you don’t need to read Chinese to look at pictures and you can see the cell at the centre of the problem is the macrophage/monocyte.
This is reporducible and I have seen in two other papers
The good guy or the bad guy…I suspect a bit of both as time matters and what happens in the first week or two is probably key. Sadly this would be the time to get anti-virals, so we are doing the hardest experiment again but treating people once they are hospitalised.
However, remember most MS drugs are not going to touch this element, so your journey could be the same, MS drug or not. I think one will hit this proces soon after delivery and one will probably will target this. The experiment has happened to see if this is a good or bad thing, what will the answer be, it will come out in the MS registries.
However do MS drugs hit CD8 T cells? . The answer is substantially yes for for one, maybe for another and not that much for most. At the moment I think I would like the CD8 T cells to be around. They may be dropping because the COVID-19 virus can get into T cells and whilst they are not going to become virus factories, they can be triggered to commit suicide. The lymph glands are also shrinking due to viral activity. If the CD8 T cells drop too much, it is a bad indicator for severe things to come.
However, it suggests the solution is not simple, but I don’t think the recommendations for MS have taken into account the biology. However, what does the biology mean? As for use of steroids in severe COVID-19 currently being trialled, answers are emerging of the likely outcome. Time will tell.