Safe
Antibodies mimicking the virus may explain long haul COVID-19, rare vaccine side effects
As for COVID-19 vaccines, the primary antigen used is the SARS-CoV-2 spike protein. According to Murphy and Longo, current research studies on antibody responses to these vaccines mainly focus on the initial protective responses and virus-neutralizing efficacy, rather than other long-term aspects.
“With the incredible impact of the pandemic and our reliance on vaccines as our primary weapon, there is an immense need for more basic science research to understand the complex immunological pathways at play. This need follows to what it takes to keep the protective responses going, as well as to the potential unwanted side effects of both the infection and the different SARS-CoV-2 vaccine types, especially as boosting is now applied,” Murphy said. “The good news is that these are testable questions that can be partially addressed in the laboratory, and in fact, have been used with other viral models.”
And Effective
Immune escape of SARS-CoV-2 Omicron variant from mRNA vaccination-elicited RBD-specific memory B cells.
This response is nonetheless waning with time. We and others
have been able to show that SARS-CoV-2-specific memory B cells (MBCs) represents a potent layer
of additional immune protection. MBCs not only persist after infection but continuously evolve and mature by
progressive acquisition of somatic mutations in their variable region genes to improve affinity through
an ongoing germinal center response.
Upon restimulation, either in the context of natural infection or vaccinal boost, MBCs can rapidly
differentiate into the plasma cell lineage, secreting the diverse array of high-affinity antibodies
contained in the their repertoire. Deep analysis of the repertoire of vaccinated individuals has so far
suggested that a sizeable proportion of such MBCs is able to neutralize all VOCs up to the Beta variant.
A non-peer reviewed preprint suggests that SARS-CoV-2
Omicron escapes to a large extent vaccine-elicited antibodies or antibodies from SARS-CoV-2
recovered sera. Yet, the intrinsic capacity of the MBC pool to recognize Omicron
variant still remains unexplored.
We show here that the unique accumulation of mutations in
key amino acid residues within the RBD of the Omicron variant results in a loss of affinity of 70%
MBCs clones, greatly bypassing the Wuhan (WT) RBD-driven affinity-maturation process occurring
in the germinal centers of infected and/or vaccinated individuals.
it is difficult to give a precise
range but one would expect that the available neutralizing MBC repertoire against the Omicron variant could fall closer to (or below) 10% of the overall anti-RBD MBC repertoire in most individuals. This
low frequency of available protective MBC repertoire would represent a marked decrease compared to
the 40 to 80% detected against the original SARS-CoV-2 in most donors(Sokal et al., 2021b).
analyzing sera collected from individuals that
had received a mRNA recall vaccination mobilizing the MBC pool, either a third vaccine dose in naive
individuals or a unique dose in previously infected individuals. In both cases, a more than 5-fold
reduction in neutralization efficacy against the Omicron variant was measured as compared to the
Wuhan (WT) and Delta strains
MBCs are endowed with great proliferative
potential and, at a rate of one division every 10-12 hours, could theoretically compensate for an up to
8-fold loss in protective clone frequency in less than 2 days
https://jamescintolo.substack.com/p/-vaccine-side-effects-and-long-haul
https://health.ucdavis.edu/newsroom/news/headlines/antibodies-mimicking-the-virus-may-explain-long-haul-covid-19-rare-vaccine-side-effects/2021/11
