Just this morning a journalist sent me a link to a press release about a new paper looking at how SARS-Cov-2 affects the vascular system, & asked to comment on it for a article. If you’d like to read the actual paper you can find it here, but be aware that it does get complex in places (it’s an in vivo study using hamsters as the host organism). I found it really interesting – as the researchers say, it “could open the door for new research into more effective therapies.”
The spike proteins are the structures projecting from the virus, and they’re what the immune system learns to recognise (and then attack). SARS-Cov-2 uses them to connect to host cells, before its genetic material is moved into the cell & used to force the cell to make more viruses. The spikes don’t just latch onto cells randomly but bind to a particular receptor protein in the cell membrane called ACE2 (this paper gives a good description of that process). These receptors are common in many tissues & one of those tissues is the cells lining blood vessels & lungs (aka “vascular endothelium”).
We already knew that the virus does a lot of damage via its replication process, because cells are damaged/destroyed when the new virus particles emerge from the cells where they were made. What this paper appears to show is that the spike protein itself can cause damage to those endothelial cells, doing this by lowering the production of the ACE2 protein and interfering with the cell’s mitochondria.
Remember that the researchers used a “pseudovirus” to do this: a modified adenovirus with spike proteins on its surface. The authors note this as a limitation of the study and comment that their findings need to be confirmed in studies using the intact SARS-Cov-2 virus itself. And they say this (my emphasis):
This conclusion suggests that vaccination-generated antibody and/or exogenous antibody against S protein not only protects the host from SARS-CoV-2 infectivity but also inhibits S protein-imposed endothelial injury.
That is, they are highlighting the value of vaccination against the virus, because they feel it would protect both infections in the first place, and against the activity of the spike protein.
Since the Pfizer (& Moderna) vaccines cause the vaccinated individual to produce the spike protein in their own cells, I guess the obvious question is, could this be problematic in the way described in the paper?
Here’s why I think the answer is no.
The vaccine is administered into muscle tissue (it’s an intramuscular injection), not into the bloodstream. When the lipid-enclosed packages containing the vaccine’s mRNA bump into a cell’s membrane, they fuse, letting the mRNA enter the cell. Once inside, each mRNA molecule is used by the cell to manufacture the spike protein. (This happens for only a few days, after which the mRNA is broken down and its parts recycled.)
Some of the spikes move to the cell membrane and project through it – they aren’t floating around loose outside the cell – and fragments of the protein are presented (again on the outside of the cell) by other specialised proteins. Both the protruding spikes and the presented fragments are visible & accessible to cells of the immune system, which interact with them in the process of generating an immune response. Similarly, when a vaccinated cell reaches the end of its life, the proteins & fragments are snaffled up by immune cells, along with the other cellular debris. Once the immune system has recognised and made antibodies to the spike proteins, the antibodies bind to the spikes, which means they can’t attach to other cells. (The New York Times had a really good explainer on this.)
So it’s highly improbable that vaccination would result in a massive flood of spike proteins into the vascular system (bearing in mind that what I described in the last paragraph is happening largely in muscle cells around the immediate vaccination siteA). And – as the authors of the paper itself imply – vaccination-generated antibodies would sweep up any that were released upon the death of the cells producing them.
A While Voices for Freedom would like to suggest that the vaccine makes us “walking spike protein factories”, this is thus hardly the case. Incidentally, the researchers didn’t use “virus-free spike protein” either – did VfF not read the paper before commenting to the Newshub reporter?
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