With respect to the receptors it is interesting the photo or artistic impressions that papers , tv and websites have used. There appear to be various shapes on effectively the Corona 'Keys' (effectively two, one to enter the body and into the cell under cloaking, one to move within the cell and one to move (or be moved to as food or similar source) to the nucleus, but some have shown the same shape, now is that shape important and is it a physical key or a chemical (protein, enzyme, or carbon chain key ?)
Viruses, or should I say virions don’t have a food source, all they do is reproduce. I am not sure of the exact mechanism of entry here or form of the receptors here I would have to read up, but we are taking biochemical shapes, and they are known and do have a specific name. I read about it whilst still in France but with a rather deflected mind at the time
The receptors on the surface of the cells are usually protein in nature but it is usually a specific part of the protein that is chemically recognised like a lock and key fit. This shape is VERY. Important. I think , but don’t quote me on it that the virus deactivates the immune system to allow it to enter the cell. In the cell the virus takes over the protein manufacture system of the cell, or host as it now is. This is where the Nucleic acid or genetic code of the virus comes in. It takes over the protein production mechanism blocking the host cells own DNA/RNA action so that the host cell now uses the virus genetic code to make the virus proteins own that make up its structure as well as replicating the nucleic acid of the virus itself . The new nucleic acid and proteins reassemble to form new viruses, each cell will contain millions of them. That is the mechanism for all viruses although it is far more complex than that involving numerous biochemistry reactions, and enzymes which if I did know them I no longer do. The Host cell eventually dies as all its own functions have been stopped this death releases the virus to infect other cells it can attach to.
On the plus side, the activity of the virus distorts the host cell causing what I seem to remember is called the cytopathological effect. The bodies immune system will recognise these as non self cells, ie they don’t belong and this triggers part of the immune system reaction to destroy tge. And the viruses inside. Some of the immune reaction is to the virus itself and the surface receptors. I think the vaccine research involves blocking the receptors on the virus or preventing the replication process in the cell but I think there are other more novel approaches.
I do not proclaim to be an expert here on this and my memory is a little vague on specifics but I can do some extra research or Tiz may now. He is more up to date on modern research ideas.
https://www.immunology.org/public-infor ... eplication
https://www.statnews.com/2020/04/10/cor ... -receptor/
https://www.nih.gov/news-events/nih-res ... treatments
This one is hard going
https://www.sciencedirect.com/science/a ... 8220300827