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Comment by jart | Hacker News Reader

There have been successful FOI requests in other countries. Japan managed to get Pfizer to cough up some of their animal testing research https://files.catbox.moe/0vwcmj.pdf which has measurements of the lipid nanoparticle concentration in the brain, eyes, ovaries, etc. Does anyone know if there are similar measurements available for conventional vaccines? Since it'd be nice to be able to compare these numbers to something.

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Looks pretty good I’d say.

After giving a rat a 50ug dose (a single dose for a human is 30ug), the % of administered dose in the brain was .009, eyes .003, and heart .030. Comparatively, the injection site was 24.6 and liver 16.2.

Also, some of these rats were given some big ol’ doses. 1 mg RNA / kg.

What is the better measurement, % of total administered dose or the ug/g concentration? The latter shows a relatively high does for some organs, particularly liver, spleen, and ovaries. As a layman, it seems like the latter would be the better metric as it's a normalized value but I assume you chose the former for a valid reason.

I'd rather see number of nanoparticles per cell. There's about 300,000 eggs in an ovary and 300 are ovulated in a lifetime. Eggs are cells and cells weigh 1 nanogram each. Virus particles weigh less than a femtogram. I assume the same applies to these lipid nanoparticles. So by my calculation that would be 123 lipid nanoparticles for each cell in the ovaries. `1e-9 / (0.1e-3 * 1e-12) * (12.3e-6)`. Pfizer's drug works by programming cells to produce spike proteins on the membrane so that the immune system recognizes them as the enemy and destroys them. I wish I knew why Pfizer needed to choose a delivery method for their drug that crosses the blood brain barrier and accumulates a 10x concentration in the ovaries. Since modern delivery technologies are so advanced that they should have been able to do something less systemic.

What are you looking to compare? Conventional inactivated or attenuated pathogen vaccines don't use lipid nanoparticles at all, so the number will be 0 (barring some kind of contamination or measurement error).

Inactivitated pathogens are themselves nanoparticles. Many pathogens even are made of lipids as well.

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