Can COVID-Vaccines Cause Long Covid?
This will be a short one.
Someone on Twitter told me off and said “if there was any evidence the vaccines caused Long COVID we would know about it”. After laughing I replied back
I then did a bit of research and found this
“In rare cases, coronavirus vaccines may cause Long Covid–like symptoms-Brain fog, headaches, blood pressure swings are being probed by NIH and other researchers”
It links to this article:
“A Possible Role for Anti-idiotype Antibodies in SARS-CoV-2 Infection and Vaccination”
https://www.nejm.org/doi/full/10.1056/NEJMcibr2113694
Its a bit technical but VDJ recombination is what makes each humans adoptive immune system unique.
Before getting to the study lets review some immunology regarding the process of selecting gene segments for B-Cell Receptors (BCR)
So it is this uniqueness which explains some of the variability in a how a virus affects l people. It explains, all else being equal, why some of us don’t get very sick but others die. The beauty of this is that its unlikely a single virus could wipe out humanity. It also means a virus or vaccine that is harmless to 99.9% could harm you
The paper explains
“VDJ recombination results in new and therefore immunogenic amino acid sequences called idiotopes, which are then capable of inducing specific antibodies against Ab1 antibodies as a form of down-regulation.
The paratopes, or antigen-binding domains, of some of the resulting anti-idiotype (or “Ab2”) antibodies that are specific for Ab1 can structurally resemble that of the original antigens themselves.
Thus, the Ab2 antigen-binding region can potentially represent an exact mirror image of the initial targeted antigen in the Ab1 response, and Ab2 antibodies have even been examined for potential use as a surrogate for the antigen in vaccine studies.
However, as a result of this mimicry, Ab2 antibodies also have the potential to bind the same receptor that the original antigen was targeting .
Ab2 antibodies binding to the original receptor on normal cells therefore have the potential to mediate profound effects on the cell that could result in pathologic changes, particularly in the long term — long after the original antigen itself has disappeared.
The S protein itself has a direct effect on suppressing ACE2 signaling by a variety of mechanisms and can also directly trigger toll-like receptors and induce inflammatory cytokines. Anti-idiotype responses may affect ACE2 function, resulting in similar effects.
The reported occurrence of myocarditis after vaccine administration bears striking similarities to the myocarditis associated with Ab2 antibodies induced after some viral infections.
Ab2 antibodies could also mediate neurologic effects of SARS-CoV-2 infection or vaccines, given the expression of ACE2 on neuronal tissues, the specific neuropathologic effects of SARS-CoV-2 infection,and the similarity of these effects to Ab2-mediated neurologic effects observed in other viral models.
https://www.nejm.org/doi/full/10.1056/NEJMcibr2113694
😅Translation: Ab2 antibodies in this case are specific for ACE2 which decrease ACE2 activity. This could lead to an increase in the abundance of Ang II, which causes a proinflammatory state that triggers symptoms of PASC(Long Covid)