… I’ve got the bit between my teeth and I’m just throwing this out there…
Do you remember the kerfuffle surrounding the AstraZeneca shot and its efficacy regarding the first and second shot in clinical trials where it turned out that giving less was actually MORE effective.
Well, reading Antibody-Dependent Enhancement (ADE) of Coronavirus Entry, this can, indeed, be a “thing”.
This research, originally published in December 2019, suggests that less is more but then can be less again; see extract below and my words are in square brackets.
“Accordingly, three different sets of results were obtained. First, as the amount of Mersmab1 [the antibody] increased, viral entry into DPP4-expressing HEK293T cells continuously dropped (Fig. 6A). This result reveals that Mersmab1 blocks the DPP4-dependent viral entry pathway by outcompeting DPP4 for binding to MERS-CoV spike. Second, as the amount of Mersmab1 increased, viral entry into CD32A-expressing HEK293T cells first increased and then decreased (Fig. 6A). The turning point was about 100βng/ml of Mersmab1. A likely explanation for this result is as follows: at low concentrations, more MAb [antibody] molecules enhance the indirect interactions between MERS-CoV spike and the Fc receptor; at high concentrations, MAb molecules saturate the cell surface Fc receptor molecules and then further bind to MERS-CoV spike and block the indirect interactions between MERS-CoV spike and the Fc receptor. Third, as the amount of Mersmab1 increased, viral entry into cells expressing both DPP4 and CD32A first dropped, then increased, and finally dropped again (Fig. 6B).”
Now, I know that antibodies are created pretty quickly after either viral infection or vaccination, so, in the case of vaccination, the level of antibodies may depend upon the strength of the vaccination.
Certainly this was observed in the AstraZeneca trial.
And is it also supported by the UK Government’s one shot policy – which, incidentally, was not supported by AstraZeneca?
You can bet that SAGE are aware of Antibody-Dependent Enhancement.
So, where am I going with all of this?
I think, where I end up right now (because my head is fried and I should really be getting on with something else) is that, unlike mathematics, this biotechnology is an inexact science; and one where currently we are the guinea pigs.
We are, indeed, flying by the seat of our collective pants!
A viral crisis in the form of Covid-19 has caused the politicians to push the boundaries of medical science (in my “glass half full” opinion they are doing so in good faith and there is NO global conspiracy run by the illuminati).
Ultimately this will be a good thing. But right now, we are on the cutting (bleeding?) edge of developments.
And despite the news coming out from the snoutlets, we collectively do NOT have all of the answers.
This countermeasure (vaccination program) may well be a huge success; it might not.
I’m sure the cleverer people than me are anxiously looking out for signs of ADE in secondary “new variant” SARS-CoV-2 infections.
Meanwhile people are partying hard in Israel right now… Let’s hope they don’t all wake up with a lethal hangover.
We will have to watch and see.
