****Note: I pinged JimNoble as perhaps he can answer the question as to whether our immune response is keyed almost exclusively or just mainly to the Spike protein when it comes to enveloped viruses and whether antibodies targeting the Membrane or even possibly Envelope proteins would make a significant difference in immune response. I honestly don’t know, but find it a very, very interesting question and would love to know the answer.****
Thank you for your thoughtful and well-reasoned comment — which made me do some more thinking, too. I am not an expert, either. What you wrote here makes a lot of sense:
>>>”As I understand it, when the human immune system begins to produce anti-bodies to a virus, it is keying in, not just on one characteristic of the virus, such as the spike protein signature, but on a number of viral signatures, whereas with the “vaccine” the immune system produces anti-bodies ONLY to the spike protein and nothing else. So, upon any re-infection, the natural immunity has a wider variety of anti-bodies to attack the virus.”<<<
My understanding, however, is that, when it comes to enveloped viruses, our immune system mainly (almost exclusively?) zeroes in on the spike protein. Is that correct? Well, not being sure whether I remembered correctly, I went and checked (link given later in this post — it’s a very long article I found fascinating, but others may not)):
>>>”Despite a spectrum of differences in their biology and pathogenesis, all enveloped viruses share two commonalities: a lipid bilayer envelope co-opted from host cells upon viral egress and the presence of surface-exposed viral glycoproteins for host cell recognition and entry. These viral glycoproteins or ‘spike’ proteins are exposed to the adaptive immune response and are the main targets of host antibodies, often being the only exposed antigen.” (from page 2 — see also fig. 1 and its accompanying text)<<<
Also:
>>>”The overwhelming majority of antibodies that provide sterilizing protection from infection target the viral spike. Therefore, the structure of the glycoprotein greatly influences how antibodies are selected, matured and specifically interfere with the mechanics of viral entry.”<<<
It appears that one area of vulnerability our antibodies seek to exploit and attack is the area near the base of the “stalk” where the “spike” attaches to the membrane of the virus. So I suppose it might be possible that enveloped viruses’ membrane proteins theoretically *could* have a role — but I really don’t know. When you look at the mechanics of how our antibodies attack and disable the viruses’ machinery, it does not seem likely to be significant to me, but again, I am not a doctor or microbiologist.
Link to article:
Antibody responses to viral infections: a structural perspective across three different enveloped viruses
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6818971/#!po=5.22388
Classic view link (easier to search):
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6818971/?report=classic
I can see why they chose the spike protein, given the above. Of course no one wanted to mess with a vaccine using the whole virus considering the disastrous results of the SARS1 vaccine animal tests:
https://pubmed.ncbi.nlm.nih.gov/22536382/
Link to list of proteins expressed by the Covid virus:
>>>>”In addition to these genes, SARS-CoV-2 contains genes that encode four structural proteins which are involved in infectious virus assembly: (S)pike, (E)nvelope), (M)embrane, and (N)ucleocapsid) proteins. The N protein holds the RNA genome, and the S, E, and M proteins together create the viral envelope. The spike protein is responsible for allowing the virus to attach to and fuse with the membrane of a host cell. Interspersed between these genes in the coronavirus genome are several other genes called “group-specific or accessory genes” and their gene products are called “accessory proteins” that are dispensable for virus growth in vitro, but may play an important role in modulating the host response to virus infection and thereby, contribute to pathogenesis.”<<<<
https://www.ncbi.nlm.nih.gov/Structure/SARS-CoV-2.html
Oops. I got so interested in that question, I forgot to address the last part of your comment.
Yes, every vaccine (and drug) has its risks. We have to look at the risk/benefit ratio. According to this study, it looks like young males would have done better taking their chances with catching Covid over taking the Moderna vaccine:
https://www.nature.com/articles/s41591-021-01630-0
The smallpox vaccines administered to our troops also had their risks (including myocarditis):
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4368609/
I agree about the Covid vaccines not being subjected to the long (7-10 years) clinical trials vaccines normally have to pass before becoming available to the general public. It was utterly horrifying to me that anyone would think it was okay to *mandate* a vaccine issued under an EUA.
Without such rigorous trials, there was no way to calculate a proper risk/benefit ratio. Now we know that, for young males, the risk/benefit ratio comes down on the side of taking one’s chances with actually contracting Covid is preferable to taking the Moderna vaccine (see first link). But we did not know that back when. There is a whole lot we know now we did not know back when.
I think the jury is still out on mRNA vaccines. The Covid vaccines are the only ones to ever be tried out on human beings on a large scale. As you can see from my second link, the old smallpox vaccines also had considerable risks, especially for young males. Again, I totally agree about the lengthy trials for previous vaccines vs the rushed Covid vaccines.